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Author Topic: Skylon Spaceplane  (Read 74263 times)

Offline SteveO

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Skylon Spaceplane
« on: September 09, 2007, 10:13:07 am »
I've seen the Reaction Engines Ltd Skylon spaceplane mentioned a few times already but I think it deserves it's own thread.

It looks cool and will only cost £10 billion(ish) to develop, so if it wasn't designed in Great Britain 'the land of lost opportunties' it would probably get built ;)

It looks pretty feasible and practical to me, what are your views on it?

Check out the website http://www.reactionengines.co.uk/ and A E Mann's fantastic artwork.

 

« Last Edit: September 09, 2007, 11:03:16 am by overscan »

Offline Orionblamblam

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Re: Skylon Spaceplane
« Reply #1 on: September 09, 2007, 10:48:32 am »
what are your views on it?

I always figured it'd snap in half on re-entry.
« Last Edit: September 09, 2007, 11:04:18 am by overscan »
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Offline flateric

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Re: Skylon Spaceplane
« Reply #2 on: September 09, 2007, 11:00:53 am »
It looks cool and will only cost £10 billion(ish) to develop

...how many times have we heard something like this...Energia Kliper estimates, for example, were '...just USD 880 mln"...interesting that this chedevre of Russian car industry, for example, was USD 2,4 bln to put into series. Other part of my wants Alan Bond to succeed, of course.
« Last Edit: September 09, 2007, 11:07:20 am by flateric »
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Offline Orionblamblam

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Re: Skylon Spaceplane
« Reply #3 on: September 09, 2007, 06:30:33 pm »
It looks cool and will only cost £10 billion(ish) to develop

...how many times have we heard something like this...

The problem here is that for Skylon to work, a number of currently unbuilt technologies would all need to be built and proven out. It'd suck to go ahead and build the thing only to find out that the engines will invariably stall out at Mach 8.3 due to some as-yet unseen physical principle. Ooops.
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Offline flateric

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Re: Skylon Spaceplane
« Reply #4 on: September 10, 2007, 12:54:51 am »
Interesting, was LACE ever operationally tested in flight ever?
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Offline Orionblamblam

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Re: Skylon Spaceplane
« Reply #5 on: September 10, 2007, 12:38:50 pm »
Interesting, was LACE ever operationally tested in flight ever?

Not as far as I'm aware. I would not be surprised if some componant testing was done... say, a KC-135 with an air liquifaction rig set up, but I'd be stunned if air was liquified, stored, and then fed into an engine to provide thrust. I'd be freakin' flabbergasted to discover that a complete LACE system that was anywhere near flightweight was ever *built,* much less flown.
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Offline Michel Van

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Re: Skylon Spaceplane
« Reply #6 on: September 10, 2007, 01:04:13 pm »
here Model of Sabre Engine



and who it sould work



back to LACE
was static Test of that engine ?
and wat of his "evil Brother" NULACE ?
NU stands for NUCLEAR  :o
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Offline SteveO

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Re: Skylon Spaceplane
« Reply #7 on: April 26, 2009, 12:14:05 pm »
Whatever we all think of Skylon I think we'll agree this video is pretty good  ;D

Skylon mission animation http://www.reactionengines.co.uk/skylon_ops_anim.html

Offline Proponent

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Re: Skylon Spaceplane
« Reply #8 on: May 04, 2009, 08:14:09 am »
It looks pretty feasible and practical to me, what are your views on it?

At first glance it seems like a no-brainer that an air-breathing vehicle makes sense.  A launch vehicle sitting on the pad is 90+ percent propellant, half or more of which is oxygen.  If you could get all of that oxygen "for free" from the atmosphere, then the lift-off weight would drop dramatically.  Not only would you not need to carry all of that oxygen and tankage for it, but for each kilo of oxygen you didn't carry, you'd need less fuel and hence smaller fuel tanks.  Now that you've got a much smaller vehicle (less than half the size), it should be cheaper to operate.

But when you start to think about the details, things don't look so rosy.  IIRC, scramjet SSTO designs usually switch from scramjet mode to rocket mode at a few kilometers per second, well below orbital velocity.  Things are better than they seem for the scramjet, because a conventional rocket will have burned more than half of its propellant just to get to, say, 1.5 km/s, but we're still a long way from orbit at the stage that a rocket has to take over anyway.

Then there's the fact that launch vehicles try to get out of the atmosphere quickly, to avoid drag losses and heating.  A scramjet-based vehicle, on the other hand, must remain in the atmosphere longer.  It will suffer higher drag losses and its structure will need to cope with substantial heating.

There is a fundamental limitation on how much the scramjet can help.  Getting to orbit is a matter of lifting yourself up to, say, 200 km and accelerating to about 7 km/s.  The first takes an energy of about (9.8 m/s2) * (200,000 m) or about 2 MJ/kg.  The second takes about 0.5 * (7,000 m/s)^2 or about 25 MJ/kg.  Now just think about all of that oxygen that your scramjet scoops up.  It is stationary with respect to the earth's surface.  Hence, although you don't have to lift the oxygen, you do have to accelerate it to your own speed, just to avoid slowing down, and then you have to accelerate it some more in order to get some thrust out of it.  Taking oxygen from the air helps with the 2 MJ/kg of lifting that has to be done to reach orbit, but it doesn't help with the much larger 25 MJ/kg's worth of accelerating that has to be done.

Even though scramjet SSTO designs switch from air-breathing mode to rocket mode at relatively low speeds, the stationarity of the air reduces the efficiency of the engine.  Suppose we're burning hydrogen, which gives us an exhaust velocity of about 4,000 m/s in a rocket engine, where the oxygen that is delivered to the combustion chamber is more or less stationary with respect to the chamber.  At 4,000 m/s, the oxygen atoms in the exhaust contain a kinetic energy of about 0.5 * (4,000 m/s)^2 = 8 megajoules per kilogram.  That's about how much useful energy we're extracting from combustion.  In the case of the scramjet, our oxygen come screaming in at, say, 1,500 km/s, so it has a kinetic energy of 1.125 MJ/kg.  Now we add 8 MJ/kg through combustion (assuming we can burn as efficiently as in a rocket engine, which is unlikely) to get a specific energy of 9.125 MJ/kg, corresponding to an exhaust velocity with respect to the atmosphere of 4,270 m/s.  So, with respect to the vehicle, the exhaust velocity is not 4,000 m/s, but just 4,272 m/s - 1,500 m/s = 2,770 m/s.  The simple fact that the oxygen we scoop up is stationary makes our engine less efficient.  [NB: This quick-and-dirty analysis ignores the hydrogen in the mass-energy balance, but it's a modest fraction of the total mass.]  The faster we go, the worse this problem gets.  The problem will be worse, too, if we use a hydrocarbon fuel, which has a lower exhaust velocity.  And this ignores the fact that the air we scoop up is mostly nitrogen, not oxygen.  I know there are ways of dealing with the nitrogen, but they add complexity and inefficiency.


IMHO scramjets are interesting and deserve further research.  But for SSTO applications, scramjet technology will have to be very much more mature than it is now to be worth the trouble.

Offline Simon666

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Re: Skylon Spaceplane
« Reply #9 on: May 05, 2009, 01:44:47 am »
The simple fact that the oxygen we scoop up is stationary makes our engine less efficient. 
Are you confusing ramjets and scramjets? Throughflow in a scramjet engine is supersonic, to avoid the heat and pressure generated as compared to slowing to subsonic in a ramjet.

Offline Proponent

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Re: Skylon Spaceplane
« Reply #10 on: May 05, 2009, 02:52:24 am »
The simple fact that the oxygen we scoop up is stationary makes our engine less efficient. 
Are you confusing ramjets and scramjets? Throughflow in a scramjet engine is supersonic, to avoid the heat and pressure generated as compared to slowing to subsonic in a ramjet.

My quick-and-dirty analysis is the best-case scenario, in which there are no losses due to slowing of the inflow as it passes through the engine.  As you point out, scramjets will operate closer to this limit than ramjets can, but they are still subject to it.

Offline PMN1

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Re: Skylon Spaceplane
« Reply #11 on: October 07, 2009, 09:09:30 am »
Interesting news in this month’s Spaceflight

The British spaceplane developer Reaction Engines celebrated its 20th anniversary in mid-August and revealed that it is planning to fly its Skylon spaceplane for the first time in 2018.

Also

Preliminary studies have begun to develop a larger version of the Skylon design. Skylon D1 will be capable of carrying a 25 percent larger payload into orbit than the current design. It will also be approximately 340 tonnes in weight at take off compared with the current 275 tonnes.
« Last Edit: October 07, 2009, 09:11:40 am by PMN1 »

Offline FutureSpaceTourist

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Re: Skylon Spaceplane
« Reply #12 on: April 17, 2010, 01:50:03 am »
A few months ago Reaction Engines released issue 1 of a 52 page Skylon User Manual for prospective clients! You can download it from http://www.reactionengines.co.uk/downloads/SKYLON_User_%20Manual_rev1%5b3%5d.pdf.

Offline aemann

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Re: Skylon Spaceplane
« Reply #13 on: May 13, 2010, 02:51:20 pm »
The SABRE engine is neither a Ramjet nor a Scramjet - "The SABRE engine is a combined cycle engine which air-breathes like a jet engine but with a pre-cooler heat exchanger in front of the turbine compressor. There is a secondary bypass ramjet in the nacelle, but this is subsonic combustion and so not a Scramjet."

The key to making it work is the heat exchanger, and the associated frost control. The engines can't stall at M 8.3, as they transition from air breathing to rocket mode at about M5.

They've been testing the pre-cooler heat exchanger at their test facility, and it's looking very good indeed. The only other major hurdle was demonstrating that a rocket can be cooled with LOX, and there's just been a successful test by EADS Astrium. They're currently refining the the design from the C1 config that is in all the illustrations, to the D1. Even I haven't seen that yet, but it will apparently be sufficiently different that you won't have to be a rivet counter to see the changes.

Surely it makes more sense to invest in technology like this - unproven or otherwise - than going back to building yet another missile and capsule system? Whatever happens, it'll create something new, or new ways of thinking about these problems at least. And you know what, it might just work... imagine that! A proper reusable system, on demand, with a decent payload that'll make access to space truly routine. I'm so disappointed that someone like Elon Musk with all his cash, has the 'vision' to build... a missile with a capsule. Here - build this instead, and change the world forever.

Offline Orionblamblam

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Re: Skylon Spaceplane
« Reply #14 on: May 13, 2010, 03:05:41 pm »
Surely it makes more sense to invest in technology like this - unproven or otherwise - than going back to building yet another missile and capsule system?

It depends greatly on what your end product and schedules are. if your goal is to have a relatively inexpensive manned launch system within a decade, then clearly you want to go with known technologies. If your goal is to spend lots and lots of money in the hope that several decades down the line you *might* develop a new piece of technology that will do something that simpler tech already does, then hey, by all means, invest in the unproven.

Rocket engines work. SABER engines, scramjets, liquid air cycle engines, MHD ramjets... don't. Not yet at any rate. And there's no good evidence that spending X millions will make them work, and even less evidence that after all that time and expense you'll have a technology that will make operations any cheaper, never mind procurement costs.
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Offline FutureSpaceTourist

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Re: Skylon Spaceplane
« Reply #15 on: May 13, 2010, 09:07:27 pm »
As I understand it Reaction Engines' business plan isn't that they need Skylon to be developed and successful to generate any ROI.  Instead they're looking to be a heat exchanger technology company and so could be starting to make a return quite soon.

True the company has already been going for many years, but it's a small company and has been generating some income. So I'd guess that the private investment so far is a lot less than Elon Musk has put into SpaceX. Probably more like the amount John Carmack has invested in Armadillo?

More details of their recent work, referred to above, and a new video are in their latest newsletter: http://www.reactionengines.co.uk/news_apr10.html

Offline PMN1

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Re: Skylon Spaceplane
« Reply #16 on: May 14, 2010, 01:17:22 pm »


More details of their recent work, referred to above, and a new video are in their latest newsletter: http://www.reactionengines.co.uk/news_apr10.html

Yeah, Brian Blessed

http://www.reactionengines.co.uk/splm_movie_flash.html

Offline SteveO

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Re: Skylon Spaceplane
« Reply #17 on: May 15, 2010, 02:25:11 pm »

Offline Kevin Renner

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Re: Skylon Spaceplane
« Reply #18 on: May 17, 2010, 03:03:45 pm »
Gee, the 'Blue Danube' for a musical score. How original  ::) ::)

Offline FutureSpaceTourist

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Re: Skylon Spaceplane
« Reply #19 on: June 06, 2010, 09:53:20 pm »
Another new video http://www.reactionengines.co.uk/troy_movieqt.html is in REL's May monthly update (http://www.reactionengines.co.uk/news_may10.html).

This is a concept animation of their proposed Troy Mars mission, which of course uses Skylon to get the necessary components to LEO. Further details on Troy are in the paper at http://www.reactionengines.co.uk/downloads/mars_troy.pdf.

Offline SteveO

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Re: Skylon Spaceplane
« Reply #20 on: June 07, 2010, 07:26:29 am »
Nice, Adrian Mann's work is excellent.

As much as I love Skylon and anything like it, I can see wormhole/Compression Space Transport technology arriving before any hardware gets built  ;D

http://www.peterfhamilton.co.uk/index.php?page=Pandora_s_Star
http://www.peterfhamilton.co.uk/index.php?page=saul-estrada

Offline Michel Van

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Re: Skylon Spaceplane
« Reply #21 on: June 07, 2010, 08:08:27 am »
that little bit of topic

but it's sooo hilarious
Bilion Dollar project to put man on Mars, only to beaten by geeks

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Offline FutureSpaceTourist

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Re: Skylon Spaceplane
« Reply #22 on: June 07, 2010, 09:29:40 am »
As much as I love Skylon and anything like it, I can see wormhole/Compression Space Transport technology arriving before any hardware gets built  ;D

I know what you mean ;)

As I see it, a big issue for obtaining funds to even attempt to build Skylon is lack of a roadmap from proving basic technologies (such as current heat exchanger work) to the billions needed for a full vehicle. Maybe Reaction Engines have such a plan and it's too commercially sensitive to discuss. But like you I can't see it happening without some smaller - and useful - intermediate development steps.

P.S. That's pre-supposing it's all technically achievable, which isn't a universally held view ...
« Last Edit: June 07, 2010, 09:33:13 am by FutureSpaceTourist »

Offline airrocket

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Re: Skylon Spaceplane
« Reply #23 on: June 30, 2010, 06:25:26 pm »
Japan "baraban pre-cooler" followed recently in India with Russian assistance. Sabre is deeply cooled rocket not a scram or a ram converts to all rocket around mach5-6 then pitch up to orbit. And fact is Japan and India are way ahead of Reaction deep cooled technology.
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Offline RanulfC

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Re: Skylon Spaceplane
« Reply #24 on: July 01, 2010, 08:43:34 am »
Japan "baraban pre-cooler" followed recently in India with Russian assistance. Sabre is deeply cooled rocket not a scram or a ram converts to all rocket around mach5-6 then pitch up to orbit. And fact is Japan and India are way ahead of Reaction deep cooled technology.
This sounds WAY too familar... I'm thinking I've heard of this before in relation to the RASCAL program. I seem to recall a report showing a "deep-cooled turbo-rocket" called the "KIL-N" cycle I think?? Basiclly it used an RL-10 engine fed by LH2 and Liquid Air drawn from a set of compressor intakes and heat-exchangers...

I'll see what I can find again.

Randy

Offline edwest

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Skylon - space transport
« Reply #25 on: September 17, 2010, 12:32:12 pm »

Offline Orionblamblam

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Re: Skylon - space transport
« Reply #26 on: September 17, 2010, 02:35:53 pm »
I would let to get the learned opinions of the members about this proposal:

My opinion: the editor who came up with the title is a MORON.

"spaceplane that will take tourists into orbit at five times the speed of sound"

Gah.

"The Skylon’s innovative engine uses propulsion to reach the edge of the Earth’s atmosphere..."

Astounding! It uses propulsion!
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Offline FutureSpaceTourist

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Re: Skylon Spaceplane
« Reply #27 on: September 17, 2010, 04:58:30 pm »
The Daily Mail article listed above is a rehash of http://www.theengineer.co.uk/in-depth/analysis/out-of-this-world/1004713.article.

Reaction Engines also recently made a submission to a parliamentary select committee on the new UK Space Agency (see http://www.publications.parliament.uk/pa/cm201011/cmselect/cmsctech/memo/space/m09.htm).

The submission contains the following interesting titbit:

Quote
Since the [UK Space] Agency was formed the main interaction with Reaction Engines has related to the organising of a major international review of the SKYLON spaceplane to be held on 20th to 21st September. This review will host over 100 experts from around the world to assess the economic and technical aspects of the SKYLON concept. The outcome of this Review, supported by an evaluation from the European Space Agency will give the UK Government confidence that, should further support to project be given, it will be on the basis of a thorough assessment.

Offline FutureSpaceTourist

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Re: Skylon Spaceplane
« Reply #28 on: October 04, 2010, 05:47:32 pm »
Reaction Engines' September newsletter includes the following about the recent review:

Quote from: http://www.reactionengines.co.uk/news_sept10.html
On 20th and 21st September, the UK Space Agency held a System Requirements Review on the commercial and technical capabilities of SKYLON at the International Space Innovation Centre at Harwell, England. Approximately ninety invited experts attended the event venturing from various European and global nations including the USA, Russia, India, Japan and South Korea. In the months leading up to the Review, three engineers from the European Space Agency (ESA)  were seconded to REL in order to investigate our technology, methods and analysis. ESA will provide the UK Space Agency with an official report on the Workshop within in the next month.

The preliminary results of the event are indicative that the majority of the attendees consider SKYLON to be a viable concept. Responses to questions on the project provided a clear and honest overview of the programme. Dr Constantinos Stavrinidis, Head of Mechanical Engineering at ESA, gave the closing address and commended the competence of REL and its SKYLON concept.

REL hopes that the feasibility of the SKYLON programme is no longer in doubt and that the commercial and technical aspects of the project are well understood and recognised. Over the coming months, discussions with government, industry and private investment are due to take place and REL looks forward to further progressing SKYLON.

The UK Space Agency’s press release for the event is available at http://www.ukspaceagency.bis.gov.uk/19661.aspx?pf=1

Recently, one of the recurring questions has been the degree of government involvement in the SKYLON development. To date, the public contribution stands at 15% with the remaining 85% provided by private investment. REL intends SKYLON to remain as commercial a programme as possible.

Offline Matej

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Re: Skylon Spaceplane
« Reply #29 on: October 05, 2010, 02:00:30 am »
I had a looong talk with the Reaction Engines representatives, a very usefull one, so when I will have some free time to spare, I will write some extract of it.

Bizarre aviation expert.

Offline mz

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Re: Skylon Spaceplane
« Reply #30 on: October 05, 2010, 02:24:50 am »
EDIT: Oh found already some spreadsheet materials on their homepage so my questions have been partly answered at least.
http://www.reactionengines.co.uk/pdf_documents.html
« Last Edit: October 05, 2010, 02:28:57 am by mz »

Offline SteveO

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Re: Skylon Spaceplane
« Reply #31 on: October 06, 2010, 11:23:00 am »
I had a looong talk with the Reaction Engines representatives, a very usefull one, so when I will have some free time to spare, I will write some extract of it.
Thanks Matej, will look forward to it.

Nice pic of the SABRE, lots to get right and lots that can go wrong there!

Offline FutureSpaceTourist

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Conceptual space station serviced by Skylon
« Reply #32 on: November 21, 2010, 02:06:16 pm »
Here's a nice piece of concept art that I can't resist sharing!



You can download a fairly high-res version from the artist's (fugimel) web page at http://feguimel.deviantart.com/art/Comm-CLARKE-SpaceStation-186411464?fullview=1. There's a little bit of background to it in this rocketeers blog posting.

Offline Nik

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Re: Skylon Spaceplane
« Reply #33 on: November 22, 2010, 05:34:32 am »
Oh, wow ! That's a blast from the Golden Age of rocketry !!

FWIW, I think the station should be a polygonal toroid so that segments would lack compound curves and *would* fit in cargo bay...

Offline Michel Van

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Re: Skylon Spaceplane
« Reply #34 on: November 22, 2010, 06:33:31 am »
Oh, wow ! That's a blast from the Golden Age of rocketry !!

FWIW, I think the station should be a polygonal toroid so that segments would lack compound curves and *would* fit in cargo bay...

that is inflatable toroid segments (see concept art)
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Offline OM

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Re: Skylon Spaceplane
« Reply #35 on: November 22, 2010, 07:38:14 pm »
FWIW, I think the station should be a polygonal toroid so that segments would lack compound curves and *would* fit in cargo bay...

...There have been concepts that allow for compound curves in structures that can be fit in a conventional cylindrical cargo shroud/bay. They involve stacking smaller segments rotated 180 degrees from each other, thus aligning them along one axis as a cylinder. When orbit has been achieved, the whole stack is removed, the segments rotated, and as much as a 1/4 arc of a complete toroid results. Note that a 1/4 arc required a serious lift booster, and the more conservative concepts I've read about called for arcs of only 1/6 or 1/8.

Wish I still had those papers that discussed these concepts. The diagrams were actually quite detailed in the stacking and deployment phase.

Offline FutureSpaceTourist

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Re: Skylon Spaceplane
« Reply #36 on: April 18, 2011, 03:15:38 pm »
Reaction Engines have a key test of their precooler technology coming up in June. But what I find most interesting about the following report is the claim that they have $350M worth of funding lined-up contingent on the precooler working!

Quote from: http://www.space.com/11414-skylon-space-plane-british-engine-test.html
Big Test Looms for British Space Plane Concept

SAN FRANCISCO — A huge, unmanned British space plane is on pace to start launching payloads into Earth orbit in less than a decade — provided it can pass a crucial engine test in June, its designers say.

[...]

The atmospheric air whooshing into the SABRE engines at high speeds would be extremely hot. But for the engines to work efficiently during the air-breathing stage, that air needs to be cooled substantially — down to about minus 238 degrees Fahrenheit (minus 150 degrees Celsius) — before being compressed and reacted with the onboard hydrogen.

That's what the big test in June is for. Skylon engineers have developed a new "precooler" system to do the job. The system will get its first big test in the June trials.

If the precooler works, investors will chip in another $350 million, helping take the Skylon project to another level of development. That next phase would likely see vehicle design completion and a full engine demonstration by 2014

Offline Nik

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Skylon Spaceplane pre-cooler
« Reply #37 on: April 20, 2011, 07:22:20 am »
IIRC, *if* the pre-cooler works, then they'll license it to Euro-consortium who want to build an antipodal Mach-5 jet liner aka 'Lapcat'. No rockets, pure air-breathing, but Europe to Australia in five (5) hours flat...

The cash-flow from that bootstraps Skylon development, first just air-breathing to Mach 5 for heat-soak and structural / handling / control stuff, then upgrade to full SABRE engines and push envelope towards orbit...

Sounds like a plan...

Offline FutureSpaceTourist

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Re: Skylon Spaceplane
« Reply #38 on: April 20, 2011, 07:31:48 am »
I thought Lapcat was just an EU funded study, not something that would ever be built! Who's putting up the billions required to fund development?!

Offline CNH

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Re: Skylon Spaceplane
« Reply #39 on: April 20, 2011, 04:04:17 pm »
Europe to Australia in 5 hours? ROFL. Who wants to go to Australia any way? [Maybe some would like to come back ...] Seriously, there are what ... 20 million people in Oz? Not exactly a mass market.

As for Mach 5 and the rest - has no one learned anything from Concorde? Supersonic flight over land is a big no no.

Offline Nik

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Re: Skylon Spaceplane
« Reply #40 on: April 20, 2011, 05:05:58 pm »
My understanding is that they would fly a lot higher than Concorde, so the boom is reduced. Besides, if you don't need to stop in Middle East to refuel...

Offline RLBH

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Re: Skylon Spaceplane
« Reply #41 on: April 20, 2011, 11:35:57 pm »
Actually, I believe their proposed route passes over the Arctic ocean, through the Bering straits and over the Pacific ocean. Technically, this is actually a westerly route to Australia, and a return flight up the Red and Adriatic Seas would allow you to go supersonic most of the way, whilst making the combined round trip count as a circumnavigation.

Offline shockonlip

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Re: Skylon Spaceplane
« Reply #42 on: April 21, 2011, 12:16:01 am »
Europe to Australia in 5 hours? ROFL. Who wants to go to Australia any way? [Maybe some would like to come back ...] Seriously, there are what ... 20 million people in Oz? Not exactly a mass market.

As for Mach 5 and the rest - has no one learned anything from Concorde? Supersonic flight over land is a big no no.

Haven't you heard? You don't have to go to Australia !

The Australians will come to the UK, and park their scramjets at Heathrow !

Last week at the 2011 Spaceplanes Conference in San Fransicso, they presented 3 papers on the next phase
of their 20 year development roadmap using scramjets and rockets for access to space entitled SCRAMSPACE
"(Scramjet-based Access-to-Space Systems) an Australian Space Research Program funded
project that represents the first phase of this road map. SCRAMSPACE is centred around an affordable, expertise
building flight at the scramjet entry point to the access-to-space Mach range (M8-M12). The flight will address
scramjet performance, materials, and instrumentation, supported by ground-based performance and vehicle control
developments in this range. Future phases of the road map will progressively incorporate scramjet technologies,
currently being developed in Australian hypersonics laboratories, into flight experiments of increasing speed and
sophistication. Ultimately, scramjet and rocket technologies will be brought together to demonstrate a prototype
hybrid rocket / scramjet access-to-space system".

Offline Michel Van

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Re: Skylon Spaceplane
« Reply #43 on: April 21, 2011, 01:32:12 am »
Europe to Australia in 5 hours? ROFL. Who wants to go to Australia any way? [Maybe some would like to come back ...] Seriously, there are what ... 20 million people in Oz? Not exactly a mass market.

As for Mach 5 and the rest - has no one learned anything from Concorde? Supersonic flight over land is a big no no.

I wanna visit Oz, (but entry permit and customs inspection are hell)
there other market for Mach 5, like route like China/ Japan  to USA or Europe
Skylon precursor BAe HOTOL was also proposed as hypersonic passenger craft !
50 persons form London to Sydney in 45 Minute
with engine boostphase almost to orbit, then glide to Airport like Space shuttle
http://www.secretprojects.co.uk/forum/index.php/topic,277.msg93538.html#msg93538


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Re: Skylon Spaceplane
« Reply #44 on: April 25, 2011, 08:47:24 am »
The boom may be reduced, but it'll still be there. So it leaves Heathrow - where is it when it hits Mach 1?

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Re: Skylon Spaceplane
« Reply #45 on: May 01, 2011, 02:08:22 am »
I had a looong talk with the Reaction Engines representatives, a very usefull one, so when I will have some free time to spare, I will write some extract of it.

I think its about time...

So, my first impression is that they perfectly know, what they are doing. I was not overwhelmed by the megalomaniac plans to conquer the universe. They have a very clean, simple and realistic point-to-point strategy, mostly related to the propulsion system. Regarding the vehicle - for now its just the preferred concept without solved details.

When speaking about the engine, they used already developed and proved technologies and they even did some work on joining and testing them together as one connected system. There was only one unproved technology left - precooling system. In the mid 2010 they were preparing to test this last piece of puzzle and as FutureSpaceTourist pointed out, they are going to launch those tests this summer. The point-to-point strategy gave them the advantage to be able to request the funds not for the all-new complex, complicated and expensive engine, but rather to the separate technologies, that can have also other applications, not only in the SABRE engine. It means, that even if the Skylon will never be realized, they will be usefull in the other industry areas. What I found very interesting is that they were able to collect (thanks to that kind of strategy) relatively a lot of money. They started with the specific studies/analysis with the costs of hundreds of thousands Eur, then they were working with the millions and now they collected tens of millions in funds. That is impressive. So when they claim that there are the investors ready to spent 350M USD after the successfull precooler test, it is not a surprise for me. Honestly, if I be the investor, I would really consider to give them some money for the engine technology development.

Another story is the vehicle. Because they are concentrating almost all the efforts to the propulsion, vehicle is now in its concept stage. They made the preliminary work on the aerodynamics and some subsystems, but it seemed to me that they didn't figure out some of the important details. The thermal protection system is one of the examples - I surprised them a bit with that question. They said that they can use some sort of the  modern ceramic tiles, but when I argue by the complexity, expense and the different size/shape of almost all of the  tiles on the Space Shuttle, I didn't receive any good answer. It means for me that there is still the probability, that the design of the vehicle can change, as they start the detailed work on it in the next phase. I also couldn't resist to use the Scott's note that it would snap in half on reentry. They answered in detail and generally it was about the argument, that the vehicle will have the very low weight during the reentry compared to the takeoff and also it will have very provident trajectory.

To summarize it, they absolutely convinced me that the SABRE engine is the right thing to do and I am sure it can be realized. Regarding the Skylon vehicle, well, it belongs to the group of the much realistic European vehicles, however I am carefull in this case. If it ever became reality, we are talking about beyond 2025 timeframe.

Bizarre aviation expert.

Offline Archibald

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Re: Skylon Spaceplane
« Reply #46 on: May 01, 2011, 03:31:37 am »
I had a looong talk with the Reaction Engines representatives, a very usefull one, so when I will have some free time to spare, I will write some extract of it.

I think its about time...

So, my first impression is that they perfectly know, what they are doing. I was not overwhelmed by the megalomaniac plans to conquer the universe. They have a very clean, simple and realistic point-to-point strategy, mostly related to the propulsion system. Regarding the vehicle - for now its just the preferred concept without solved details.

When speaking about the engine, they used already developed and proved technologies and they even did some work on joining and testing them together as one connected system. There was only one unproved technology left - precooling system. In the mid 2010 they were preparing to test this last piece of puzzle and as FutureSpaceTourist pointed out, they are going to launch those tests this summer. The point-to-point strategy gave them the advantage to be able to request the funds not for the all-new complex, complicated and expensive engine, but rather to the separate technologies, that can have also other applications, not only in the SABRE engine. It means, that even if the Skylon will never be realized, they will be usefull in the other industry areas. What I found very interesting is that they were able to collect (thanks to that kind of strategy) relatively a lot of money. They started with the specific studies/analysis with the costs of hundreds of thousands Eur, then they were working with the millions and now they collected tens of millions in funds. That is impressive. So when they claim that there are the investors ready to spent 350M USD after the successfull precooler test, it is not a surprise for me. Honestly, if I be the investor, I would really consider to give them some money for the engine technology development.

Another story is the vehicle. Because they are concentrating almost all the efforts to the propulsion, vehicle is now in its concept stage. They made the preliminary work on the aerodynamics and some subsystems, but it seemed to me that they didn't figure out some of the important details. The thermal protection system is one of the examples - I surprised them a bit with that question. They said that they can use some sort of the  modern ceramic tiles, but when I argue by the complexity, expense and the different size/shape of almost all of the  tiles on the Space Shuttle, I didn't receive any good answer. It means for me that there is still the probability, that the design of the vehicle can change, as they start the detailed work on it in the next phase. I also couldn't resist to use the Scott's note that it would snap in half on reentry. They answered in detail and generally it was about the argument, that the vehicle will have the very low weight during the reentry compared to the takeoff and also it will have very provident trajectory.

To summarize it, they absolutely convinced me that the SABRE engine is the right thing to do and I am sure it can be realized. Regarding the Skylon vehicle, well, it belongs to the group of the much realistic European vehicles, however I am carefull in this case. If it ever became reality, we are talking about beyond 2025 timeframe.

Lots of good points there - I think you nailed their strategy quite well. They focuse on the hardest part first - the engine.
If they obtain a workable engine, fine. I just hope that workable engine can then find its way on a workable spaceplane.

a while back at  NASA spaceflight.com Mark Hempsell briefly discussed Skylon. http://forum.nasaspaceflight.com/index.php?topic=21530.180
And there, too (better thread)
http://forum.nasaspaceflight.com/index.php?topic=22434.msg627560#msg627560




« Last Edit: May 01, 2011, 09:46:20 am by Archibald »
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Offline FutureSpaceTourist

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Re: Skylon Spaceplane
« Reply #47 on: May 01, 2011, 04:34:40 am »
Thank you both for the extra information, very interesting.

If they obtain a workable engine, fine. I just hope that workable engine can then find its way on a workable spaceplane.

Quite! But even if the spaceplane doesn't materialise, I like to hope that the technology will still be used in some aerospace vehicle that members of this website would appreciate  :)

Offline Nik

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Skylon Spaceplane review "without showstoppers".
« Reply #48 on: May 24, 2011, 03:56:56 am »
BBC TV teletext news reported this morning that ESA technical review of Reaction Engine's Skylon & Sabre gave them a clean bill, "without show-stoppers". Next phase is to be ground-testing of a jet engine with pre-cooler.
 ;D
http://www.bbc.co.uk/news/science-environment-13506289

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Re: Skylon Spaceplane review "without showstoppers".
« Reply #49 on: May 24, 2011, 04:04:04 am »
BBC TV teletext news reported this morning that ESA technical review of Reaction Engine's Skylon & Sabre gave them a clean bill, "without show-stoppers". Next phase is to be ground-testing of a jet engine with pre-cooler.
 ;D
http://www.bbc.co.uk/news/science-environment-13506289


Good news, but they better get a move on with regards as to the airframe front!
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Offline martinbayer

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Re: Skylon Spaceplane
« Reply #50 on: May 24, 2011, 08:00:58 am »
Would be marching to the beat of his own drum, if he didn't detest marching to any drumbeat at all so much.

Offline Archibald

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Re: Skylon Spaceplane
« Reply #51 on: May 25, 2011, 10:17:32 am »
I used to be skeptical about Skylon (SSTO ? bah. Spaceplane ? re-bah) but recent events changed my mind. That thing might really work in the end.
Kudos to Alan Bond, who survived HOTOL failure and fifteen years (1993 - 2008) of low profile research, trying to prove his concept might work. The effort payed!

Then, if Skylon ever flies, it will open a whole can of worms. Von Braun shuttle; Sanger antipodal bomber. Reagan's Orient Express; see what I mean ?
« Last Edit: May 25, 2011, 10:19:28 am by Archibald »
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Offline mz

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Re: Skylon Spaceplane
« Reply #52 on: May 25, 2011, 12:46:43 pm »
ESA assessment report is available here: http://www.bis.gov.uk/assets/bispartners/ukspaceagency/docs/skylon-assessment-report-pub.pdf

Martin

Thanks, that was a very interesting read. Having read some about rigid airships, the thing actually does resemble them more than airplanes like is said there.

I'm still not convinced it would be cheaper to develop or operate than a two stage reusable rocket.

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Re: Skylon Spaceplane
« Reply #53 on: July 06, 2011, 05:01:25 am »
The Skylon spaceplane project has several go/no-go points and the first of these is the full-scale test of the frost-control on the engine precooler.
The full-scale precooler was, according to various reports due to be tested in June. We're now into July and nary a sign of a precooler test or any results.

When will we see if the project will make it past its first, and possibly most critical hurdle?

Offline Nik

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Re: Skylon Spaceplane
« Reply #54 on: July 06, 2011, 06:04:14 am »
No news since ~ May 11 2011
http://www.reactionengines.co.uk/index.html


However, the page on the heat-exchanger says 'during 2011'...


I'd hope everything worked so well that they went back and triple-checked, to be sure, to be sure...

Offline FutureSpaceTourist

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Re: Skylon Spaceplane
« Reply #55 on: July 06, 2011, 02:03:56 pm »
Reaction Engines' June newsletter is now on-line but nothing substantive yet on the pre-cooler tests:

Quote from: http://www.reactionengines.co.uk/news_jun11.html
Commencement of Pre-cooler Heat Exchanger Testing Process
The testing process for the pre-cooler heat exchanger technology began this month. Over the past few months, the B9 test site has been stripped down and the dummy pre-cooler has been removed and placed in storage. The Viper jet engine has been refurbished in preparation for the testing. 

The pipe runs for both the helium loop and N2 supply have been tested. The helium loop instrumentation and control for the operation of the valves are also in place.

Offline bazz

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Re: Skylon Spaceplane
« Reply #56 on: July 08, 2011, 03:34:59 am »
I'm still not convinced it would be cheaper to develop or operate than a two stage reusable rocket.

I have been following Skylon for a long time as I was always a fan of HOTOL.

They reckon initially $40m a launch and with a fleet on the go they could get it down to $10m per launch whether that is realistic is anyones guess. They reckon Skylon could orbit 5 tonnes (33069 lb) and I believe that is to GTO. I wonfer how does the Ariane 5 compare?

I really hope they can do it, it is such a cool project and even if they can get a working Sabre engine out of the deal there is huge potential to sell it to the space/defense industry.

I can't help feeling that inorder to achieve a feasible air frame they will need outside help who knows maybe in 20 years BAE and reaction could team up and Britain could be leading the way in payload delivery.

Good luck to them I say!

Offline Kharkov

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Re: Skylon Spaceplane
« Reply #57 on: July 08, 2011, 06:39:49 am »
In 2009, Mark Hempsell of REL appeared on the Space Show (still available for podcast download - check wikipedia page for Skylon) and said that, if Skylon didn't work out, they'd go to a 2-stage vehicle.

The problem, he said is that it would double the cost because you'd need a fortune to develop the carrier aircraft and the same again for the to-orbit vehicle.

Personally, I'd say that the 2nd stage vehicle would carry less than the Skylon because of the limitations on weight that the 1st stage could carry.

Offline Archibald

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Re: Skylon Spaceplane
« Reply #58 on: July 09, 2011, 06:10:10 am »
Well, they could team with Mitchell Burnside Clapp to bring the Black Horse / Black Colt / Pathfinder lineage back.

Pull a Black Arrow - Gamma 8 - H202/kerosene rocket engine out of a museum, fire it on the bench.
Have an Airbus or Boeing tanker modified for inflight refueling of H2O2.
Use space shuttle components  to save some costs.
Upper stages - any cryogenic or Breez or Block D would be fine.

There you go... that thing might work IF one don't try orbital SSTO straight on (Black Horse). Suborbital with an upper stage (Black Colt or Pathfinder) is doable with today's technology.

To max payload, modify an A380 as a tanker  :D
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Offline PMN1

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Re: Skylon Spaceplane
« Reply #59 on: July 09, 2011, 09:48:27 am »
Mark Hempsell has got involved in this discussion here

http://forum.nasaspaceflight.com/index.php?topic=24621.0

From Page 8

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Re: Skylon Spaceplane
« Reply #60 on: September 01, 2011, 10:07:30 am »
No news since ~ May 11 2011
http://www.reactionengines.co.uk/index.html


However, the page on the heat-exchanger says 'during 2011'...


I'd hope everything worked so well that they went back and triple-checked, to be sure, to be sure...


Apparently tests have now started:


http://www.flightglobal.com/articles/2011/09/01/361501/spaceplane-engine-tests-under-way.html
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Offline FutureSpaceTourist

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Re: Skylon Spaceplane
« Reply #61 on: April 04, 2012, 11:15:27 pm »
The latest RE newsletter finally has an update on their pre-cooler testing.

Quote from: http://www.reactionengines.co.uk/news_mar12.html
Pre-cooler testing at B9 has begun

The testing of the Pre-cooler, now fully integrated into the B9 test stand with the Viper jet engine, has finally begun this month after a number of delays shaking down the system. The initial tests have gone very well and represent a good start to the test campaign which will last several months.

The flow thorough the Pre-cooler has been found to be aerodynamically stable without any significant structural deflection or vibration.
« Last Edit: April 06, 2012, 06:07:27 am by FutureSpaceTourist »

Offline Nik

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Re: Skylon Spaceplane
« Reply #62 on: April 06, 2012, 05:55:51 am »
No vibration ?


They should still get 'Eolian Harp' frequencies which, incidentally, would give convenient 'real-time' diagnostics...

Offline FutureSpaceTourist

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Re: Skylon Spaceplane
« Reply #63 on: April 24, 2012, 08:08:52 am »
Here's an interview with Alan Bond from November 2011:



He talks about various aspects of Skylon and why they believe it's technically viable. Interestingly he says that investment in the company has only been about £10 million over the last 8 years or so. That'll be dwarfed by the reported $350 million riding on the success of the current pre-cooler tests.

Offline CaseyKnight

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Re: Skylon Spaceplane
« Reply #64 on: April 24, 2012, 07:55:39 pm »
I know they've tried to eliminate icing problems, but what about FOD?

Offline FutureSpaceTourist

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Re: Skylon Spaceplane
« Reply #65 on: April 27, 2012, 04:47:06 am »
REL appear to be ratcheting up the publicity. The BBC's space/science correspondent has a piece today on Skylon and the on-going pre-cooler tests:

Quote from: http://www.bbc.co.uk/news/science-environment-17864782
[...]
Reaction Engines Limited (REL) believes the test campaign will prove the readiness of Sabre's key elements.

This being so, the firm would then approach investors to raise the £250m needed to take the project into the final design phase.

"We intend to go to the Farnborough International Air Show in July with a clear message," explained REL managing director Alan Bond.

"The message is that Britain has the next step beyond the jet engine; that we can reduce the world to four hours - the maximum time it would take to go anywhere. And that it also gives us aircraft that can go into space, replacing all the expendable rockets we use today."
[...]

At least that gives an expected date by which the pre-cooler tests will have finished!

Offline Mr London 24/7

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Re: Skylon Spaceplane
« Reply #66 on: May 15, 2012, 02:07:06 pm »

Offline aemann

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Re: Skylon Spaceplane
« Reply #67 on: May 27, 2012, 03:51:22 pm »
I am reliably informed that the first phase has gone very well i.e. nothing unexpected, and that the B9 test area is being/has been reconfigured for the next phase. It's taken longer than expected as they don't have an unlimited supply of the precooler modules, so have to be very careful with them! The precooler system does actually work - it only needs to operate for the first 10 minutes or so of the flight, but they have to actually demonstrate it to release funds for the next round. Obviously it's very intense down at REL HQ at the moment, and there's all the prep for Farnborough going on too!
FOD? Not sure I've heard anything on it, but not all the air coming through the intakes goes to the precooler - a good chunk goes down a bypass to a ring of burners at the rear - http://www.reactionengines.co.uk/sabre.html
So long as a chunk of stuff doesn't actually break the pre-cooler tubing I think it's not a big issue - they could always sweep the runway before a takeoff...  :)

Offline SteveO

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Re: Skylon Spaceplane
« Reply #68 on: May 28, 2012, 10:36:24 am »
aemann, thanks for the update. Good to hear things are progressing.

Any work being done of the airframe configuration? Is the long slender fuselage and wingtip mounted podded engines still seen as the way to go?

In otherwords have you been asked to do some more of your fantastic artwork  ;)

Offline hole in the ground

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Re: Skylon Spaceplane
« Reply #69 on: June 09, 2012, 04:40:21 am »
I too have wondered about the engines. As alan said, essentially skylon is hotol but with the fuel tank distributed either side of the wings and c of g. I guess the engines were moved to wingtips because otherwise they would be heating the rear of the fuselage, but on re-entry its surely got to get pretty hot anyway. My worry is that there is going to be an occasion when one of the engines malfunctions at some stage. I dont know how much power those engines can kick out but an asymmetry of thrust has got to be bad.

Offline Michel Van

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Re: Skylon Spaceplane
« Reply #70 on: July 06, 2012, 11:34:28 am »
here a animated Video of Skylon


SKYLON Spaceplane Passenger Logistics Module Movie


TROY Mars Mission


Skylon Progress report of 8 december 2011
http://www.stfc.ac.uk/ralspace/resources/pdf/presentation_13.pdf

bonus: Reaction Engines Lecture - Alan Bond
« Last Edit: July 06, 2012, 11:51:27 am by Michel Van »
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Offline Matej

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Re: Skylon Spaceplane
« Reply #71 on: July 13, 2012, 04:26:57 am »
Ultra Lightweight Heat Exchanger displayed during the Farnborough 2012. In Reaction Engines they are pretty convinced, that they will have Skylon-like vehicle before 2020 at least for flight tests. Again my impression was, that they perfectly know, what they want and what they are doing.

Bizarre aviation expert.

Offline AlanDavies

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Re: Skylon Spaceplane
« Reply #72 on: September 08, 2012, 09:33:09 am »
Hi apologies if this has already been covered but there is a documentary on BBC4 this coming Wednesday about Alan Bond and projects Skylon, Hotol and Blue Streak details are on the BBC website.
http://www.bbc.co.uk/programmes/b01mqv45
« Last Edit: September 08, 2012, 09:46:03 am by flateric »

Offline SteveO

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Re: Skylon Spaceplane
« Reply #73 on: September 08, 2012, 02:19:30 pm »
Thanks for the heads up Alan!

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Re: Skylon Spaceplane
« Reply #74 on: November 28, 2012, 02:40:40 am »
Latest pre-cooler tests completed, and passed according to ESA:
 
http://www.bbc.co.uk/news/science-environment-20510112
 
I was at a work event at the UK NEC a couple of weeks ago and got to hold a test piece of Skylon fuselage. Seems a little closer to reality now.  :D
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Offline hole in the ground

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Re: Skylon Spaceplane
« Reply #76 on: February 20, 2013, 02:21:08 pm »
[OT}narrated by bryan blessed?![/OT]

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Re: Skylon Spaceplane
« Reply #77 on: July 16, 2013, 05:46:14 am »
UK government supporting SABRE engine development:

http://www.guardian.co.uk/science/2013/jul/16/60m-space-rocket-engine
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Offline PaulMM (Overscan)

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Re: Skylon Spaceplane
« Reply #78 on: July 16, 2013, 05:57:00 am »
[OT}narrated by bryan blessed?![/OT]


SKYLON'S AAALLLIIIVVVEEEE!
"They can't see our arses for dust."
 
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Offline Vahe Demirjian

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Re: Skylon Spaceplane
« Reply #79 on: July 16, 2013, 09:29:45 am »
UK government supporting SABRE engine development:

http://www.guardian.co.uk/science/2013/jul/16/60m-space-rocket-engine

Good news. That means the UK can proceed with developing the Skylon into a real-life prototype HOTOL spaceplane. Can you imagine the UK beating the rest of the world in getting a HOTOL spaceplane into orbit?

Offline Matej

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Re: Skylon Spaceplane
« Reply #80 on: July 16, 2013, 12:35:05 pm »

Bizarre aviation expert.

Offline carmelo

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Re: Skylon Spaceplane
« Reply #81 on: July 18, 2013, 12:46:38 pm »
Rule Britannia,rule the space?

Of the soyuz, Britons never will be slaves.

Offline Mat Parry

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Re: Skylon Spaceplane
« Reply #82 on: July 18, 2013, 02:01:37 pm »

Bond says ultimately REL does not envision taking on the role of engine manufacturer, but would prefer to stay focused on Sabre’s unique heat-exchanger technology.

I think that's a sensible (and insightful) ambition. let somebody else rule space, we will rule the heat-exchanger market

Offline shockonlip

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Re: Skylon Spaceplane
« Reply #83 on: July 18, 2013, 04:48:51 pm »

Bond says ultimately REL does not envision taking on the role of engine manufacturer, but would prefer to stay focused on Sabre’s unique heat-exchanger technology.

I think that's a sensible (and insightful) ambition. let somebody else rule space, we will rule the heat-exchanger market

And just who do you suppose will take over the full scale engine development and validation/verification?
I don't get the logic of this. It's like P&W saying they developed the gearbox and overall design for a geared turbofan at reduced scale and now wants someone else to do the full up engine development and manufacture.

Perhaps Bond is going to address different levels of heat exchanger technology.
Perhaps some can be adapted to existing engines. Like different levels of
cooling to increase overall engine pressure ratio.
 

Offline sferrin

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Re: Skylon Spaceplane
« Reply #84 on: July 18, 2013, 05:49:55 pm »
Skylon is a perfect example of the tortoise in the tortoise/hare race.  The US's efforts seem to be the hare. 
"DARPA Hard"  It ain't what it use to be.

Offline Hobbes

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Re: Skylon Spaceplane
« Reply #85 on: July 18, 2013, 11:54:37 pm »

And just who do you suppose will take over the full scale engine development and validation/verification?
I don't get the logic of this. It's like P&W saying they developed the gearbox and overall design for a geared turbofan at reduced scale and now wants someone else to do the full up engine development and manufacture.

No, it's not. REL have developed the heat exchanger, but they have no experience designing jet engines. Getting into that game would require huge additional investment. It makes sense leaving the jet component of the SABRE to a jet engine manufacturer.

Offline Mat Parry

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Re: Skylon Spaceplane
« Reply #86 on: July 19, 2013, 12:33:51 am »
Maybe it's a reflection of having a technical mind at the helm and not a business mind, the techie wants to focus on their area of expertise and not dilute their efforts by building capabilities outside their core competance, the Business mind wants to grow the the enterprise to maximise profits.. and rule the world..... Muwhahaha!


Realistically however, Britain (or even Europe) to build a space plane on our own? I think the sun has set on those kinds of ambitions. I hope I'm wrong however because I would travel anywhere on Earth to see that bird fly

Offline Rhinocrates

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Re: Skylon Spaceplane
« Reply #87 on: July 19, 2013, 02:25:51 am »

It makes sense leaving the jet component of the SABRE to a jet engine manufacturer.


That's the way a lot of business is done nowadays - outsource and co-ordinate the assembly of the final product instead of building up the capital and resources to do it all in-house.


Honestly, I get the willies whenever Elon Musk announces that he's working on a new project - don't spread yourself too thin, I think, know your competence and your resources, get people to help you to do it, don't try to do everything until you know it's working.


Then that's probably why I'm not a billionaire.
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Re: Skylon Spaceplane
« Reply #88 on: July 23, 2013, 10:10:07 am »

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Re: Skylon Spaceplane
« Reply #89 on: October 25, 2013, 10:07:15 am »

Offline FighterJock

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Re: Skylon Spaceplane
« Reply #90 on: October 26, 2013, 12:27:50 pm »
Reaction Engines expands research project to build full-sized air-breathing engine - http://www.flightglobal.com/blogs/hyperbola/2013/10/reaction-engines-expands-sabre-engine-project-to-finance-full-engine/

Progress!  :)

http://www.reactionengines.co.uk/


Let's us hope that Skylon succeeds where its predecessor HOTOL failed.  As a member of the British Interplanetary Society I have seen several papers of the Skylon spaceplane and the SABRE engine in their technical Journal JBIS over the years.
« Last Edit: October 26, 2013, 12:40:44 pm by FighterJock »

Offline sublight is back

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Re: Skylon Spaceplane
« Reply #91 on: October 30, 2013, 02:52:35 pm »
From the web site.
Quote
At Mach 5 (5 times the speed of sound) the heat exchanger needs to cool air from 1,000°C to minus 150°C, in 1/100th of a second, displacing 400 Mega-Watts of heat energy (equivalent to the power output of a typical gas-powered power station) yet weighs less than 1¼ tonnes.
Anyone care to hazard a guess how that is going to work?

Offline SteveO

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Re: Skylon Spaceplane
« Reply #92 on: October 30, 2013, 05:11:49 pm »
From the web site.
Quote
At Mach 5 (5 times the speed of sound) the heat exchanger needs to cool air from 1,000°C to minus 150°C, in 1/100th of a second, displacing 400 Mega-Watts of heat energy (equivalent to the power output of a typical gas-powered power station) yet weighs less than 1¼ tonnes.
Anyone care to hazard a guess how that is going to work?
Clever people will build something clever  :)
A variable intake and a very efficient heat exchanger help. The website should have more detail.

Offline Dragon029

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Re: Skylon Spaceplane
« Reply #93 on: October 31, 2013, 05:24:45 am »
From the web site.
Quote
At Mach 5 (5 times the speed of sound) the heat exchanger needs to cool air from 1,000°C to minus 150°C, in 1/100th of a second, displacing 400 Mega-Watts of heat energy (equivalent to the power output of a typical gas-powered power station) yet weighs less than 1¼ tonnes.
Anyone care to hazard a guess how that is going to work?

Through their patented / secret design. You'd think it to be a scam or hoax, but the simple fact is, their technology has passed all of it's trials so far.

Offline blackstar

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Re: Skylon Spaceplane
« Reply #94 on: October 31, 2013, 12:31:41 pm »
From the web site.
Quote
At Mach 5 (5 times the speed of sound) the heat exchanger needs to cool air from 1,000°C to minus 150°C, in 1/100th of a second, displacing 400 Mega-Watts of heat energy (equivalent to the power output of a typical gas-powered power station) yet weighs less than 1¼ tonnes.
Anyone care to hazard a guess how that is going to work?

Through their patented / secret design. You'd think it to be a scam or hoax, but the simple fact is, their technology has passed all of it's trials so far.

So they've gone Mach 5 already?

Offline Dragon029

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Re: Skylon Spaceplane
« Reply #95 on: November 02, 2013, 08:37:47 pm »
No, and I'm sure that'll present a myriad of technical challenges; however, tests this year and last, of the SABRE precooler have demonstrated that it can cool blown 1000C air to -150C in ~0.01 seconds.

Offline Rhinocrates

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Re: Skylon Spaceplane
« Reply #96 on: November 03, 2013, 01:18:34 am »
The big problem, I gather, was frosting - that is, the buildup of ice as the air was cooled quickly, but they've shown that they can overcome that.  That was the biggest potential showstopper apart from reentry, which is a problem for people working on the airframe, not the engine.  As Alan Bond has said many times, his focus is on the engine and that's what his company is about, so "Skylon" is really just something that will use SABRE.  They are, after all, Reaction ENGINES.

The thing that people need to keep in mind is that SABRE is an air breathing rocket, not a jet, and that Skylon is a launcher that has to compensate for and make use of the fact that Earth has an atmosphere and is not really an aircraft.



The Strathcylde design looks like a better airplane, but its embellishments add weight and make it a lesser spaceship and I worry about that - still, that's only a theoretical project.
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Offline Rhinocrates

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Re: Skylon Spaceplane
« Reply #97 on: November 03, 2013, 01:14:18 am »
For those who are interested, by the way. "Skylon" as a name has this direct inspiration:


http://en.wikipedia.org/wiki/Skylon_(tower)


A magnificent demonstation of tensile structure.
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Offline FighterJock

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Re: Skylon Spaceplane
« Reply #98 on: November 05, 2013, 08:49:11 am »
The big problem, I gather, was frosting - that is, the buildup of ice as the air was cooled quickly, but they've shown that they can overcome that.  That was the biggest potential showstopper apart from reentry, which is a problem for people working on the airframe, not the engine.  As Alan Bond has said many times, his focus is on the engine and that's what his company is about, so "Skylon" is really just something that will use SABRE.  They are, after all, Reaction ENGINES.

The thing that people need to keep in mind is that SABRE is an air breathing rocket, not a jet, and that Skylon is a launcher that has to compensate for and make use of the fact that Earth has an atmosphere and is not really an aircraft.



The Strathcylde design looks like a better airplane, but its embellishments add weight and make it a lesser spaceship and I worry about that - still, that's only a theoretical project.


Any pictures or drawings of the Strathclyde design? So I could compare them.

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Offline bigvlada

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Re: Skylon Spaceplane
« Reply #100 on: November 08, 2013, 11:39:07 pm »
From the previously mentioned document

Offline FighterJock

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Re: Skylon Spaceplane
« Reply #101 on: November 10, 2013, 09:00:30 am »
From the previously mentioned document


Many thanks, I wonder what spaceplane design they will choose to put into production for the SABRE engines.  I am torn between the Skylon and the new Strathclyde design.

Offline Nigelhg

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Re: Skylon Spaceplane
« Reply #102 on: May 29, 2014, 02:17:47 pm »
http://www.bbc.co.uk/news/science-environment-27591432

Great article on the economic case and the current state of engine development.

Offline mz

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Re: Skylon Spaceplane
« Reply #103 on: July 03, 2014, 03:13:20 am »
Nice presentation, contrasting two designs. The AFRL guy has it right, air breathing engines in general better suited for cruise missions, not acceleration like space launch.

Offline sublight is back

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Re: Skylon Spaceplane
« Reply #104 on: July 05, 2014, 08:10:38 am »
Quote
At Mach 5, air sucked into the engine goes from 1,000 Celsius to -150 Celsius in one-hundredth
of a second, and a frost control system keeps the moisture from turning into ice and clogging the heat exchanger.

This seems to be the "miracle" part. Has there been any sort of testing to verify they can pull it off?

Offline Hobbes

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Re: Skylon Spaceplane
« Reply #105 on: July 05, 2014, 11:31:06 am »
Yes, they've done lots of testing, and have submitted their design to ESA for validation.  Addressed earlier in this thread (page 6).
http://www.bbc.com/news/science-environment-20510112

Offline athpilot

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Re: Skylon Spaceplane
« Reply #106 on: December 27, 2014, 03:57:15 pm »
Skylon with Orbital Base Station (OBS). Interesting concept! It is a design for an orbital assembly complex in low Earth orbit, functioning as an integral part of a space transportation system and enabling the construction and maintenance of vehicles for the exploration of the Moon and Mars.

Offline steelpillow

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Re: Skylon Spaceplane
« Reply #107 on: December 28, 2014, 07:44:44 am »
Two things about the Skylon concept worry me.

One is the integration of turbine mode for low-speed atmospheric flight with rocket mode for high speed space flight. AFAIK nobody has yet been able to make a rocket reaction chamber capable of opening its front to ingest air (or, contrarywise, a jet exhaust capable of closing off its inlet to act as a rocket chamber). SABRE must achieve this, or it will end up as a kind of heavyweight concentric hybrid, in which fuel and oxidant flow are switched from the one combustor to the other and it becomes little more than a twin powerplant.

The other is - if all this wonder technology can do so much for the "impossible" SSO, how much could it all do for a two-stage vehicle?

These two thoughts merge if the turbine and rocket are each given their own stage, as a jet-powered carrier mothership with proto-SABRE powered second-stage orbiter. A converted A340-500 with its four Trents should just about hack it. Payload-altitude capability would be substantially more than a pure-SABRE SSO Skylon, and development costs easier to spread around.
Cheers.

Offline merriman

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Re: Skylon Spaceplane
« Reply #108 on: December 28, 2014, 08:57:25 am »
Your post suggest that there is a non-transitional switch between turbine and rocket mode. However, there is. The third propulsive mode of this engine -- one which would take the load during the air-breathing-rocket hand-over, which incidentally, operates well using air in the near-space, high-speed regeme: the ramjet.

Study the cut-aways of the SABRE engine. Note that the ramjet burners take compressed, hot air from the annular space between air-chiller and engine casing. The ramjet blasts away as the slushy air-liquid oxygen mix is transitioned over to liquid hydrogen-liquid oxygen to the four motors. The ramjet covers the transition period till the shock-cone buttons up.

[img=http://s25.postimg.org/5gnv81m4b/sabre_engine_17.jpg]

They've demonstrated the vital air cooler, now they have to come up with a compound engine injector. Just mechanics. Come on!

Bond and Musk should have a baby!

David
We're the extra fuel they may need, Stanton...

Offline steelpillow

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Re: Skylon Spaceplane
« Reply #109 on: December 28, 2014, 10:18:10 am »
Your post suggest that there is a non-transitional switch between turbine and rocket mode.
It does? I am not aware of anything on this scale that can switch modes without a transition state of some kind, I didn't think it necessary to spell that out. Shows what I know.
Cheers.

Offline Zootycoon

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Re: Skylon Spaceplane
« Reply #110 on: December 30, 2014, 12:20:58 pm »
Two things about the Skylon concept worry me.

One is the integration of turbine mode for low-speed atmospheric flight with rocket mode for high speed space flight. AFAIK nobody has yet been able to make a rocket reaction chamber capable of opening its front to ingest air (or, contrarywise, a jet exhaust capable of closing off its inlet to act as a rocket chamber).

Not correct; the solid fuel ramjet, i.e SA6/Meteor etc do exactly this as these use a common combustion chamber for both rocket and airbreathing elements.

The Sabre engine ramjet mode is not used on the assent but is available as an emergency abort the event of problem which shutting down the turbo machinery section.

A two stage launcher with a subsonic first stage is more trouble than its worth.;- all the second stage gains is about a 5% improvement from the nozzle outlet pressure matching. 

Reaction Engines (and a few years back NASA) have demonstrated a novel nozzle design which negates even this penalty.

Offline steelpillow

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Re: Skylon Spaceplane
« Reply #111 on: December 31, 2014, 03:14:30 am »
Not correct; the solid fuel ramjet, i.e SA6/Meteor etc do exactly this as these use a common combustion chamber for both rocket and airbreathing elements.
I don't regard a blob of solid fuel as a relevant control mechanism for a fluid-fuelled spaceplane. Nor FYI did Werner von Braun.

Quote
A two stage launcher with a subsonic first stage is more trouble than its worth.;- all the second stage gains is about a 5% improvement from the nozzle outlet pressure matching.
Tell that to Pegasus or Scaled Composites. OK SABRE is a little different but for the overall system there are other efficiency gains from using a launch aircraft. The conventional downside is the development cost, however that must be offset against the development cost - and risk, as above - of the full SABRE technology.
Cheers.

Offline Zootycoon

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Re: Skylon Spaceplane
« Reply #112 on: January 03, 2015, 01:00:28 pm »
 The solid fuel ramjet (aka airbreathing rocket) uses a variable area injector orifice to introduce the partially combusted gases, i.e a fluid, into the combustion can. This is precisely the component which you claim has never been done before.

The Pegasus 1 is a whole load of surplus /obsolete components cobbled together, i.e. Mx missile rocket motors, an old /unwanted airliner, etc.  If all the bits are free or bargin basement prices it's easy to make the business case. Its a very desperate solution with an orbital mass fraction of 0.2% of the runway take off weight.

The Pegasus 2 is predicted to have an orbital mass fraction about the same as a normal expendable rocket i.e about 1-2 %. There is nothing special in this configuration and  I don't understand  the interest. I guess Scale Composites make money from building bespoke one off and some of the current space business men are not demonstrating a firm understanding of the physics & engineering. 

Talking of which, the Space Shuttle sitting on top of a 747 may have looked cool but this doesn't translate to a practical launch solution, remember when on the 747 it had no fuel or payload. The high centre of gravity of the combination had to be reacted by the 747 Nose Landing Gear when braking (the design case will be the max energy RTO).  Any commercial airliner is designed to be just about strong enough to perform its intended task and doesn't have spare margins. So to estimate the mass of a piggy back orbital vehicle take the normal passenger payload weight and divide it by the increased  moment arm due to extra cg height. My guess is A340, without massive structural modifications, would be able to carry, piggyback, a 20 ton orbiter max. Skylon is designed to have a max take off weight of about 280 tons.

The only real benefit for the horizontal launch is that you don't need a vertical launch pad...... but a Skylon inherently uses horizontal launch ....... so why do anything else?

Offline steelpillow

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Re: Skylon Spaceplane
« Reply #113 on: January 03, 2015, 02:03:55 pm »
The solid fuel ramjet (aka airbreathing rocket) uses a variable area injector orifice to introduce the partially combusted gases, i.e a fluid, into the combustion can. This is precisely the component which you claim has never been done before.
Not at all. SABRE needs to fully isolate the air inlet in order to operate as a rocket in a vacuum. In the ducted rockets that I am familiar with, the valve that you are talking about controls not the air supply but the fuel-rich combustion gas supply, i.e. it operates only in a single combustion mode and is little more than a fuel throttle, and AFAIK it is not required to close fully. I am rather astonished that you have managed to confuse the two.

And like I say, if you don't get Pegasus' and Scaled Composites' business cases, take it up with them. Oh, yes, and why don't you tell Richard Branson he's been conned while you're at it, it doesn't happen to him often (though I did have to take back several copies of the original Tubular Bells release before I got a flawless one, but that was a long time ago).
Cheers.

Offline Zootycoon

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Re: Skylon Spaceplane
« Reply #114 on: January 03, 2015, 03:42:16 pm »
[quote author=Zootycoon link=topic=2455.msg239252#msg2
Not at all. SABRE needs to fully isolate the air inlet in order to operate as a rocket in a vacuum. In the ducted rockets that I am familiar with, the valve that you are talking about controls not the air supply but the fuel-rich combustion gas supply, i.e. it operates only in a single combustion mode and is little more than a fuel throttle, and AFAIK it is not required to close fully. I am rather astonished that you have managed to confuse the two.


Likewise I'm dumbfounded you believe an air isolation is so difficult. High precision variable flow at high temperature and pressure is challenging by no means impossible.

I think even if Branson hasn't figured it out yet his customers might just have.   He's in too deep and I don't believe he's behind Pegasus 2 anyway (P Allen?)

Offline steelpillow

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Re: Skylon Spaceplane
« Reply #115 on: January 04, 2015, 03:11:12 am »
Likewise I'm dumbfounded you believe an air isolation is so difficult. High precision variable flow at high temperature and pressure is challenging by no means impossible.

It is not just about isolation, it is also about having an efficient, safe and long-lived combustion chamber when the valve is closed combined with an efficient airway at all speeds when it is open. If it was that easy, it would have been done before. In practice, AFAIK engineers have in the past always resorted to dual powerplant installations, though I would be delighted to find that it has in fact been made to work.

Quote
I think even if Branson hasn't figured it out yet his customers might just have.   He's in too deep and I don't believe he's behind Pegasus 2 anyway (P Allen?)

Branson is the customer for Scaled Composites, he is not involved in Pegasus. My point is that he has a long track record of getting things right. If you think you are smarter than him, I am wasting my time talking to you.
Cheers.

Offline red admiral

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Re: Skylon Spaceplane
« Reply #116 on: January 05, 2015, 01:52:30 pm »
If memory serves, the pre-cooler ground test made use of LN2, not LHe. So I would consider this a necessary initial step towards proving the design, but not yet sufficient to say they have demonstrated it. Helium is a much different working fluid than nitrogen from both a thermodynamic standpoint as well well as from that of simple containment. The real issue with liquid air cycles is can the HEX be made mechanically strong enough to deal with all the stresses imposed on it while keeping its weight to a minimum.

The working fluid in the tests was LHe. The LN2 boiler just serves as a cooler for the LHe thats in the test because its cheaper and easier than a refrigeration plant.

Offline Gildasd

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Re: Skylon Spaceplane
« Reply #117 on: January 06, 2015, 03:38:02 am »
I'm having a bit of an issue with the thermodynamics/chemistry:

Air is at best 21% O2, so why not use O2 as the cooling medium and plumb it into the combustion chamber somewhere on the right slope of the T-s phase diagram.
Bumping the O2 content above 25% in the process instead of wasting precious He that could be better used in children's balloons?

Edit: Did not spot this:


He is reused. It's a heat transfer medium.
But N2 could still be replaced by O2, it's lower efficiency (−183 °C vs −196 °C) mitigated by it participating in the propulsion and not having the need for the He "boiler" loop.

(The other thing is that the rear lower lip of the engines would not survive re-entry.)
« Last Edit: January 06, 2015, 03:49:55 am by Gildasd »

Offline red admiral

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Re: Skylon Spaceplane
« Reply #118 on: January 08, 2015, 11:45:40 am »
I'm having a bit of an issue with the thermodynamics/chemistry:

Air is at best 21% O2, so why not use O2 as the cooling medium and plumb it into the combustion chamber somewhere on the right slope of the T-s phase diagram.
Bumping the O2 content above 25% in the process instead of wasting precious He that could be better used in children's balloons?

You'll need to put a lot of energy in to the air to cool it significantly to liquefy it and then separate the LOX before using it as a working fluid. The engine in the previous HOTOL concept did something like this but was very heavy.

Remember that the ultimate heat sink for Skylon/SABRE is the LH2 fuel - the diagram you've posted is of the test rig. In the actual engine cycle the LH2 acts as a heat sink for the LHe (which is a closed loop) and is then burnt.

Offline Zootycoon

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Re: Skylon Spaceplane
« Reply #119 on: January 08, 2015, 02:21:20 pm »
I'm having a bit of an issue with the thermodynamics/chemistry:

Air is at best 21% O2, so why not use O2 as the cooling medium and plumb it into the combustion chamber somewhere on the right slope of the T-s phase diagram.
Bumping the O2 content above 25% in the process instead of wasting precious He that could be better used in children's balloons?

You'll need to put a lot of energy in to the air to cool it significantly to liquefy it and then separate the LOX before using it as a working fluid. The engine in the previous HOTOL concept did something like this but was very heavy.

Remember that the ultimate heat sink for Skylon/SABRE is the LH2 fuel - the diagram you've posted is of the test rig. In the actual engine cycle the LH2 acts as a heat sink for the LHe (which is a closed loop) and is then burnt.

Neither HOTOL RB545 or Sabre liquefy the air. This was one of Alan's key break through beyond LACE when he found that it was possible to make the thermodynamics work whilst keeping the turbo machinery the right side of the surge line i.e. an compressor entry temperature of about -180c. This significantly economised  on the amount of LH2 required to a point a practical vehicle emerged. The He2 loop was introduced on Sabre to avoid H2 diffusion through the thin walls of the heat exchanger into air which would then posed an ignition risk within the compressor.

Offline steelpillow

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Re: Skylon Spaceplane
« Reply #120 on: January 09, 2015, 11:59:31 am »
Looks like the official description of sabre using "jet engine" technology for the airbreathing cycle has been misleading me. :( I just took a closer look at the engineering design. It doesn't work at all like a jet engine, beyond a general ability to compress air as it enters.  The important bit for me is that there's a pre-burner combustor which [feeds a heat exchanger which heats helium which] drives the air turbo-compressor. This means that the combustor which powers the compressor is a different combustor from the one which generates thrust. Hooray! No need to build high-performance mega-valves! That removes one of my concerns about the viability of SABRE. :)
Cheers.

Offline Flyaway

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Re: Skylon Spaceplane
« Reply #121 on: January 26, 2015, 11:04:49 am »
First update from Reaction Engines Limited in sometime & it's a major one.

Quote
Reaction Engines Ltd announces company growth and completion of first SABRE development milestone.

This year, the Reaction Engines team are expanding in staff and activities to complete the SABRE demonstrator programme, with delivery on track for 2019. The company has relocated to larger premises on Culham Science Centre" post= consolidated its two manufacturing subsidiaries to a single new location in Didcot; and is recruiting across the company, ready for the design, manufacture and testing of the full SABRE engine cycle. This growth phase has also included the purchase of new, bespoke equipment which will enable Reaction Engines to manufacture its proprietary SABRE pre- coolers in-house, at full scale.

Rest of the press release on the link below.

http://www.reactionengines.co.uk/press_release.html

Offline Flyaway

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Re: Skylon Spaceplane
« Reply #122 on: April 15, 2015, 08:15:17 am »
A new press release from REL and some positive news in their relationship with the AFRL. Be interesting to see where this leads.

Quote
AFRL Analysis Confirms Feasibility of the SABRE Engine Concept
Wednesday 15th April 2015
Reaction Engines Ltd. is pleased to announce that analysis undertaken by the United States’ Air Force Research Laboratory (‘AFRL’) has confirmed the feasibility of the Synergetic Air-Breathing Rocket Engine (‘SABRE’) engine cycle concept.
The analysis was undertaken by AFRL as part of a Cooperative Research and Development Agreement (‘CRADA’) with the Air Force Research Laboratory’s Aerospace Systems Directorate (AFRL/RQ). These investigations examined the thermodynamic cycle of the SABRE concept and found no significant barrier to its theoretical viability provided the engine component and integration challenges are met.
Reaction Engines Ltd. and AFRL are now formulating plans for continued collaboration on the SABRE engine; the proposed work will include investigation of vehicle concepts based on a SABRE derived propulsion system, testing of SABRE engine components and exploration of defence applications for Reaction Engines’ heat exchanger technologies.
AFRL/RQ program manager Barry Hellman stated - "The activities under the CRADA have allowed AFRL to understand the SABRE engine concept, its pre-cooler heat exchanger technology, and its cycle in more detail. Our analysis has confirmed the feasibility and potential performance of the SABRE engine cycle. While development of the SABRE represents a substantial engineering challenge, the engine cycle is a very innovative approach and warrants further investigation. The question to answer next is what benefit the SABRE could bring to high speed aerospace vehicles compared to other propulsion systems. Although application of the SABRE for single stage to orbit space access remains technically very risky as a first application, the SABRE may provide some unique advantages in more manageable two stage to orbit configurations. Furthermore, the heat exchanger technology also warrants further investigation for applications across the aerospace domain."
Sam Hutchison, Director of Corporate Development at Reaction Engines Ltd commented - “The confirmation by AFRL of the feasibility of the SABRE engine cycle has further validated our team’s own assessment and conviction that the SABRE engine represents a potential breakthrough in propulsion that could lead to game changing space access and high speed flight capability. We look forward to continued collaboration with AFRL”.
SABRE is an innovative class of aerospace propulsion that has the potential to provide efficient air- breathing thrust from standstill on the runway to speeds above Mach 5 (4,500mph) in the atmosphere – twice as fast as jet engines. The SABRE engine can then transition to a rocket mode of operation for flight at higher Mach numbers and space flight. Through its ability to ‘breathe’ air from the atmosphere, SABRE offers a significant reduction in propellant consumption compared to conventional rocket engines which have to carry their own oxygen – which is heavy. The weight saved by carrying less oxygen can be used to increase the capability of launch vehicles including options for high performance reusable launch vehicles with increased operational flexibility, such as horizontal take-off and landing. Additionally, the SABRE engine concept could potentially be configured to efficiently power aircraft flying at high supersonic and hypersonic speeds.

http://www.reactionengines.co.uk/press_release.html

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Re: Skylon Spaceplane
« Reply #123 on: April 22, 2015, 10:02:38 am »
"The real man smiles in trouble, gathers strength from distress, and grows brave by reflection." - Thomas Paine

"On what principle is it that with nothing but improvement behind us, we are to expect nothing but deterioration before us?" - Lord Macaulay

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Re: Skylon Spaceplane
« Reply #124 on: April 23, 2015, 02:46:07 am »
A new press release from REL...
Quote
Although application of the SABRE for single stage to orbit space access remains technically very risky as a first application, the SABRE may provide some unique advantages in more manageable two stage to orbit configurations.

Yes indeed. Stage separation in sub-orbital space looks sensible: SABRE gets you up there but has nothing new to offer once you are in space. Why accelerate all that thermodynamic wizardry, air ducting and empty fuel tankage on the long haul to orbital velocity, it's just dead weight. Long periods of extreme hot/cold cycles followed by hypersonic re-entry won't help its reliability engineering either.
Cheers.

Offline Flyaway

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Re: Skylon Spaceplane
« Reply #125 on: April 25, 2015, 12:31:43 am »
TBH I'd thought the Air Force would be more interested in the Scimitar engine rather than Sabre.
« Last Edit: April 27, 2015, 10:25:27 am by Flyaway »

Offline Triton

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Re: Skylon Spaceplane
« Reply #126 on: April 27, 2015, 08:55:58 am »
"SABRE engine concept passes US Air Force feasibilty test"
b David Szondy

April 26, 2015

Source:
http://www.gizmag.com/sabre-engine-afrl-feasibility-study/37092/

Quote
Reaction Engines' Skylon reusable spaceplane project has been given a boost, with analysis by the United States Air Force Research Laboratory (AFRL) confirming the feasibility of the SABRE engine cycle concept that lies at its heart.

The feasibility study conducted as part of a Cooperative Research and Development Agreement (CRADA) with the AFRL’s Aerospace Systems Directorate (AFRL/RQ) looked at the thermodynamic cycle of the SABRE concept. That is, whether the engine is able to do what Reaction Engine claims it can do. According to AFRL, there's no theoretical problem with the concept if the engine is properly built and integrated.

The SABRE (Synergetic Air-Breathing Rocket Engine) is a scramjet. That is, it reduces the propellant load because it acts as a jet while in the atmosphere and a rocket in space, so it doesn't have to carry as much oxygen to burn the liquid hydrogen fuel. It does so at velocities above Mach 5 (4,500 mph, 7,200 km/h) before flying into space, when it switches to rocket mode to achieve the even faster speeds needed to reach orbit.

The limit of the engine is how hot it gets. Above a certain point, even the best metal alloys soften and melt. At hypersonic speeds, the air is coming into the engine at 25 times more force than that of a Category 5 hurricane and the heat is like something blasting out of a cutting torch.

Paradoxically, before it can be burned, the air needs to be cooled dramatically, so as it enters the SABRE it passes over a series of heat exchangers that use the cryogenic hydrogen fuel to cool it down from 1,000° C (1,832° F) to minus 150° C (minus 302° F) in 1/100th of a second. Previously, this sort of heat exchanger was the size of a factory, but the SABRE uses one that's small and light enough to be installed inside the scramjet.

Reaction Engines and AFRL are currently collaborating on vehicle concepts that can use the SABRE engine. These not only include space launch vehicles, but also hypersonic aircraft and military applications of the Reaction Engines heat exchanger technologies.

"The activities under the CRADA have allowed AFRL to understand the SABRE engine concept, its pre-cooler heat exchanger technology, and its cycle in more detail," says AFRL/RQ program manager Barry Hellman. "Our analysis has confirmed the feasibility and potential performance of the SABRE engine cycle. While development of the SABRE represents a substantial engineering challenge, the engine cycle is a very innovative approach and warrants further investigation. The question to answer next is what benefit the SABRE could bring to high speed aerospace vehicles compared to other propulsion systems. Although application of the SABRE for single stage to orbit space access remains technically very risky as a first application, the SABRE may provide some unique advantages in more manageable two stage to orbit configurations. Furthermore, the heat exchanger technology also warrants further investigation for applications across the aerospace domain."

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Re: Skylon Spaceplane
« Reply #128 on: July 13, 2015, 05:13:48 am »
http://aviationweek.com/technology/reaction-engines-reveals-inner-secret-sabre-propulsion-technology?NL=AW-19&Issue=AW-19_20150713_AW-19_859&sfvc4enews=42&cl=article_1&utm_rid=CPEN1000000230026&utm_campaign=3138&utm_medium=email&elq2=d0dfe7ba023e4ad1bc8c0f0e4164f5f7

The development of a single-stage-to-orbit launch capability has been the Holy Grail to many since the dawn of the space age.

Yet achieving orbit in one stage with conventional rocket power is completely impractical and, despite decades of research into alternate concepts, no workable solutions have been found. It is no surprise, then, that for years the space community has been highly skeptical of claims from a British-based developer, Reaction Engines, that it had discovered an answer with a hybrid air-breathing rocket system.

But after endorsements of the basic technology from the European Space Agency and, more recently, the U.S. Air Force’s Research Laboratory, the company’s synergetic air-breathing rocket engine (Sabre) concept is being taken far more seriously. Designed to power a vehicle from a standing start to Mach 5.5 in air-breathing mode, and from the edge of the atmosphere to low earth orbit in pure rocket mode, the Sabre engine and heat exchanger at the heart of the design is attracting widespread interest for potential application on a range of atmospheric and space vehicles.
"The real man smiles in trouble, gathers strength from distress, and grows brave by reflection." - Thomas Paine

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Offline Ian33

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Re: Skylon Spaceplane
« Reply #132 on: July 29, 2015, 01:32:04 pm »
 :o

That's going to be a date with Destiny. Lordy - hope the US don't stiff them ala RB 545.
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Offline Moose

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Re: Skylon Spaceplane
« Reply #133 on: July 29, 2015, 07:31:35 pm »
http://aviationweek.com/technology/air-breathing-sabre-concept-gains-credibility

SUBSCRIBE TO ACCESS THIS PREMIUM CONTENT

 :(
Yeah sadly AvWeek has gone thermonuclear with their subscriber barrier. Some really great people at that place but whoever is calling the shots is is not my favorite person.

Offline Arjen

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Re: Skylon Spaceplane
« Reply #134 on: July 30, 2015, 12:22:24 am »
It's free membership. You register - just like you did for this site - then you get access to extra stuff. Subscribe, and you get access to even more.

<edit> Ah. The piece on Sabre *is* subscribers-only.
« Last Edit: July 30, 2015, 12:24:22 am by Arjen »

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Re: Skylon Spaceplane
« Reply #135 on: July 30, 2015, 02:46:30 am »
Aviation Week is a business, after all, while this forum doesn't have to make money.
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Re: Skylon Spaceplane
« Reply #137 on: July 30, 2015, 07:03:33 am »
Aviation Week is a business, after all, while this forum doesn't have to make money.

And a hundred bucks for what you get is chump change.  (Unlike Janes Defense Weekly. Major disappointment there.)
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Re: Skylon Spaceplane
« Reply #138 on: July 31, 2015, 10:32:16 am »
No longer subscribers-only.
Ah, thank you. However, "I acknowledge and agree to Penton's Terms of Service and to Penton's use of my contact information to communicate with me about Penton's or its third-party partners' products, services, events and research opportunities. Penton's use of the information I provide will be consistent with Penton's Privacy Policy." Said small print confirms that I will be well spammed with the above-mentioned cruft by them and every "partner" who buys my details off Aviation Week. Does that happen a lot?
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Offline TomS

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Re: Skylon Spaceplane
« Reply #139 on: July 31, 2015, 11:10:07 am »
I've been a  subscriber for a while and I don't recall seeing a whole lot of spam that obviously came from there.  Of course, I have my email on  aservice with good spam filters.

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Re: Skylon Spaceplane
« Reply #140 on: August 02, 2015, 08:18:24 am »
Thanks, that's encouraging. I'll try and pluck the courage to register.
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Offline antiquark

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Re: Skylon Spaceplane
« Reply #141 on: August 13, 2015, 09:36:08 pm »

Offline steelpillow

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Re: Skylon Spaceplane
« Reply #142 on: August 14, 2015, 02:34:06 am »
NASA just did some research on the Skylon...
http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20150015818.pdf
Wow, if ever there was a lesson in keeping well clear of the rocket exhaust!
"If the aft fuselage heating at M > 8.5 is an issue that cannot be addressed with appropriate structures and materials, then the overall design of Skylon D1.5a needs to be changed."
Let's hope they can do one or the other.

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Offline Flyaway

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Re: Skylon Spaceplane
« Reply #143 on: August 18, 2015, 12:12:15 am »
New update from REL.

Quote
Reaction Engines Ltd Announces Collaboration with Defence Science and Technology Laboratory
Monday 17 August 2015
Reaction Engines Ltd. is pleased to announce its collaboration with the United Kingdom Defence Science and Technology Laboratory (‘Dstl’).

The collaboration commenced in December 2013 and provides a framework for Dstl to assess the military utility of Reaction Engines’ Synergetic Air-Breathing Rocket Engine (‘SABRE’) and its enabling technologies. In particular, the collaboration aims to explore and evaluate the potential defence applications of REL’s heat exchanger technology.
Varunjay Ahluwalia, Technical Lead for the collaboration at Dstl, stated - “The technological advances being made by Reaction Engines could open up exciting new opportunities for defence. As part of MOD’s wider investment in disruptive technology, our collaboration with REL will enable us to explore the impact that SABRE technologies could have to current or future defence systems.”
Ben Gallagher, Business Development Lead at Reaction Engines Ltd, commented - “We are pleased to be working with Dstl to analyse and explore potential applications for our SABRE engine and heat exchanger technologies. This collaboration is a welcome addition to the portfolio of technology partnerships that Reaction Engines is participating in and we look forward to growing the relationship into the future.”

http://www.reactionengines.co.uk/news_17aug2015_rel_dstl.html

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Re: Skylon Spaceplane
« Reply #144 on: November 01, 2015, 04:10:23 pm »
BAE SYSTEMS has bought a 20% stake in Reaction Engines...

http://www.bbc.co.uk/news/business-34694935

Zeb
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Offline Flyaway

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Re: Skylon Spaceplane
« Reply #145 on: November 02, 2015, 05:23:07 am »
Must be for the military applications after the AFRL interest as BAE are primarily a defence company these days.

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Re: Skylon Spaceplane
« Reply #146 on: November 02, 2015, 02:49:28 pm »
Hopefully BAE Systems are interested in the whole Skylon concept which is to deliver a self contained payload (commercial or military) into orbit. I wonder if Rolls Royce are interested and whether Reaction Engines would be open to investment from them too? Hopefully it won't turn out like HOTOL.

SKYLON D1 paper - http://forum.nasaspaceflight.com/index.php?action=dlattach;topic=30702.0;attach=492037

Offline FighterJock

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Re: Skylon Spaceplane
« Reply #147 on: November 03, 2015, 09:27:37 am »
Hopefully BAE Systems are interested in the whole Skylon concept which is to deliver a self contained payload (commercial or military) into orbit. I wonder if Rolls Royce are interested and whether Reaction Engines would be open to investment from them too? Hopefully it won't turn out like HOTOL.

SKYLON D1 paper - http://forum.nasaspaceflight.com/index.php?action=dlattach;topic=30702.0;attach=492037

Too right SteveO,  I am old enough to remember when HOTOL got canceled.  After the Space Shuttle Challenger accident I was an early supporter of the whole Space Plane concept.

Offline Flyaway

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Re: Skylon Spaceplane
« Reply #148 on: November 03, 2015, 01:49:29 pm »
Hopefully BAE Systems are interested in the whole Skylon concept which is to deliver a self contained payload (commercial or military) into orbit. I wonder if Rolls Royce are interested and whether Reaction Engines would be open to investment from them too? Hopefully it won't turn out like HOTOL.

SKYLON D1 paper - http://forum.nasaspaceflight.com/index.php?action=dlattach;topic=30702.0;attach=492037

That might be the longer term plan, but a defence contract for the engine technology would probably represent a quicker return.

Offline steelpillow

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Re: Skylon Spaceplane
« Reply #149 on: November 07, 2015, 11:38:00 am »
HOTOL foundered because Rolls-Royce didn't believe the heat exchangers could happen and refused to invest. (B.Ae as it then was were all gung-ho and got government permission to team up with Tupolev for a piggyback-launched mini-HOTOL). Now that the key technology has been developed and proven, I'll bet Reaction Engines' buy-in price has risen. :)

Interesting that BAE Systems are still ahead of the engine men.
« Last Edit: November 07, 2015, 11:42:48 am by steelpillow »
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Offline Hobbes

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Re: Skylon Spaceplane
« Reply #150 on: November 07, 2015, 02:02:09 pm »
HOTOL foundered because Rolls-Royce didn't believe the heat exchangers could happen and refused to invest. (B.Ae as it then was were all gung-ho and got government permission to team up with Tupolev for a piggyback-launched mini-HOTOL).

I think that was Antonov (8-engined An-225), not Tupolev.

Offline steelpillow

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Re: Skylon Spaceplane
« Reply #151 on: November 08, 2015, 02:47:21 am »
HOTOL foundered because Rolls-Royce didn't believe the heat exchangers could happen and refused to invest. (B.Ae as it then was were all gung-ho and got government permission to team up with Tupolev for a piggyback-launched mini-HOTOL).

I think that was Antonov (8-engined An-225), not Tupolev.

D'oh! I knew that!

That explains why the name "Tupolev" didn't feel quite right - but, being me, I couldn't quite place why.

Thanks for the corrections.
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Offline Flyaway

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Re: Skylon Spaceplane
« Reply #152 on: March 03, 2016, 09:33:34 am »
US Military Set to Unveil Concepts Based on Skylon Space Plane Tech


Quote
Within the next year, the U.S. Air Force plans to unveil novel spacecraft concepts that would be powered by a potentially revolutionary reusable engine designed for a private space plane.

Since January 2014, the Air Force Research Laboratory (AFRL) has been developing hypersonic vehicle concepts that use the Synergetic Air-Breathing Rocket Engine (SABRE), which was invented by England-based Reaction Engines Ltd. and would propel the company's Skylon space plane.

http://www.space.com/32115-skylon-space-plane-engines-air-force-vehicle.html?cmpid=514648

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Re: Skylon Spaceplane
« Reply #153 on: March 03, 2016, 02:35:15 pm »
US Military Set to Unveil Concepts Based on Skylon Space Plane Tech


Quote
Within the next year, the U.S. Air Force plans to unveil novel spacecraft concepts that would be powered by a potentially revolutionary reusable engine designed for a private space plane.

Since January 2014, the Air Force Research Laboratory (AFRL) has been developing hypersonic vehicle concepts that use the Synergetic Air-Breathing Rocket Engine (SABRE), which was invented by England-based Reaction Engines Ltd. and would propel the company's Skylon space plane.

http://www.space.com/32115-skylon-space-plane-engines-air-force-vehicle.html?cmpid=514648
Ohhh interesting  B)
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Re: Skylon Spaceplane
« Reply #154 on: June 07, 2016, 08:23:11 pm »
http://nextbigfuture.com/2016/06/us-air-force-research-will-develop.html

Quote
The lab will reveal two-stage-to-orbit SABRE-based concepts either this September, at the American Institute of Aeronautics and Astronautics' (AIAA) SPACE 2016 conference in Long Beach, California, or in March 2017, at the 21st AIAA International Space Planes and Hypersonic Systems and Technologies Conference in China, said AFRL Aerospace Systems Directorate Aerospace Engineer Barry Hellman
"The real man smiles in trouble, gathers strength from distress, and grows brave by reflection." - Thomas Paine

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Offline steelpillow

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Re: Skylon Spaceplane
« Reply #155 on: June 08, 2016, 04:00:03 am »
Will SABRE power the first or second stage?

My guess is the first stage, as it seems a bit mental first time round to accelerate all that precooler/intercooler/compressor hardware to orbital speed in the first place, never mind hardening its intake against the destructive rigours of orbital re-entry.

OTOH you could argue that if you drop the need to fly below 400 knots or 20,000 ft or to cruise to the Equator, then that makes a SABRE orbital re-entry cycle more feasible.

Personally, first time round I would carry a sub-orbital SABRE spaceplane, with a modest internal payload bay, on top of a Jumbo jet and get that working before I got more ambitious.
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Re: Skylon Spaceplane
« Reply #156 on: June 08, 2016, 03:00:50 pm »
I missed it, what is the heat-transfer medium in the AF pre-cooler? And what kind of cycle? Hydrogen-Helium ... what?

Seems all they want to do is keep the otherwise typical GT compressor section from melting.

David
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Offline steelpillow

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Re: Skylon Spaceplane
« Reply #157 on: June 09, 2016, 12:08:06 am »
I missed it, what is the heat-transfer medium in the AF pre-cooler? And what kind of cycle? Hydrogen-Helium ... what?

Seems all they want to do is keep the otherwise typical GT compressor section from melting.

David

The heat transfer fluid in the pre-cooler heat exchanger is liquid helium, which is then used to pre-heat the liquid hydrogen fuel. And yes, the main function of the pre-cooler is to stop the turbocompressor from melting, exactly that. It also provides a first stage of compaction through cooling and even partial liquefaction, making the compressor's life doubly easy. Of course, the compressor's thermal problems do not disappear, the breakthrough is to shift them onto a precooler which can at least be purpose-designed to deal with them.

There is also some innovation in the way the thermodynamic cycle is integrated with the pumping mechanisms to provide both airbreathing and pure rocket modes. For example doubling up the helium cooler / fuel preheater as a gas generator to drive the fuel turbopump, creating what is essentially a jet engine within the main engine, is pretty neat. Note the otherwise perpetual-motion way in which helium flowing through HX4 is used to drive the fuel pump while the resulting fuel flow is used to drive the helium circulator.

From their web site at http://reactionengines.co.uk/sabre_howworks.html :

"The diagram shows in simplified form the complete SABRE cycle. The air from the intake (blue) is shown going though the Pre-cooler and into the compressor. The cooling is achieved with helium (green) that has been itself cooled by HX4 using the liquid hydrogen fuel (purple). Once it has left the Pre-cooler the helium is further heated in HX3 by the products of the Pre-burner to give it enough energy to drive the turbine and the liquid hydrogen (LH2) pump."



« Last Edit: June 09, 2016, 12:48:56 am by steelpillow »
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Offline SteveO

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Re: Skylon Spaceplane
« Reply #158 on: July 04, 2016, 03:42:16 am »
BAE Systems Hypersonic Response Aircraft concept using a Sabre type engine
Quote
Armed forces of the future could be using rapid response aircraft equipped with engines capable of propelling those aircraft to hypersonic speeds - similar to the Synergetic Air-Breathing Rocket Engine (SABRE) which is currently being developed by Reaction Engines Limited, a small British company in which BAE Systems has invested £20.6 million.

Offline TomS

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Re: Skylon Spaceplane
« Reply #159 on: July 04, 2016, 09:11:50 am »
They used a Mach 5 spaceplane to deliver 2 UAVs and a crate of supplies?  Seems a bit of a waste.

Offline Moose

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Re: Skylon Spaceplane
« Reply #160 on: July 04, 2016, 09:52:29 am »
They used a Mach 5 spaceplane to deliver 2 UAVs and a crate of supplies?  Seems a bit of a waste.
Someone's been hanging around with the SUSTAIN people too much, heh.

Offline Flyaway

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Re: Skylon Spaceplane
« Reply #161 on: July 04, 2016, 12:14:47 pm »
They used a Mach 5 spaceplane to deliver 2 UAVs and a crate of supplies?  Seems a bit of a waste.

Obviously going for a more fluffy bit of PR for some reason rather than putting forward what it's probably really for which is hypersonic strike.

Offline Ian33

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Re: Skylon Spaceplane
« Reply #162 on: July 04, 2016, 05:44:47 pm »
SHARP, meet SABRE, SABRE, SHARP.

Now, that's the introductions out the way, get jiggy, we need your babies.
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Offline Grey Havoc

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Re: Skylon Spaceplane
« Reply #163 on: July 05, 2016, 02:15:59 am »
The OPFOR Anti-Aircraft mechs were a nice touch. I wonder if the concept was from a 'blue sky' future threat study or just PR eye candy.
To the Stars

Offline Michel Van

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Re: Skylon Spaceplane
« Reply #164 on: July 05, 2016, 06:20:43 am »
BAE Systems Hypersonic Response Aircraft concept using a Sabre type engine
Quote
Armed forces of the future could be using rapid response aircraft equipped with engines capable of propelling those aircraft to hypersonic speeds - similar to the Synergetic Air-Breathing Rocket Engine (SABRE) which is currently being developed by Reaction Engines Limited, a small British company in which BAE Systems has invested £20.6 million.


War the mother of all (technical) Things
only positive in this case is that Reaction Engines Limited get more money for R&D on Sabre engine
At least BAE could build hypersonic recon plane with Sabre hardware...
I love Strange Technology

Offline CJGibson

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Re: Skylon Spaceplane
« Reply #165 on: July 05, 2016, 06:53:32 am »
BAE née BAC could build a hypersonic recon plane fifty years ago.

Chris

Offline Flyaway

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Re: Skylon Spaceplane
« Reply #166 on: July 12, 2016, 09:49:56 am »
« Last Edit: July 12, 2016, 12:25:05 pm by Flyaway »

Offline FighterJock

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Re: Skylon Spaceplane
« Reply #167 on: July 13, 2016, 08:40:05 am »
ESA COMMITS TO NEXT STAGE OF UK REVOLUTIONARY ROCKET ENGINE

http://m.esa.int/Our_Activities/Space_Engineering_Technology/ESA_commits_to_next_stage_of_UK_revolutionary_rocket_engine

BBC article with some further info on developments.

http://www.bbc.co.uk/news/science-environment-36773074

An interesting development, lets hope that Skylon succeeds where HOTOL failed.

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Re: Skylon Spaceplane
« Reply #170 on: September 21, 2016, 09:12:07 am »

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Offline Flyaway

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Re: Skylon Spaceplane
« Reply #172 on: September 29, 2016, 02:29:19 pm »
Reaction Engines Refines Hypersonic Engine Demonstrator Plan

SABRE demonstrator will be scaled for smaller-scale hypersonic and reusable launch needs

Quote
Freshly infused with government and industry funding, and riding a wave of interest in Europe and the U.S., Reaction Engines Ltd. is firming up plans to build a fighter engine-size ground demonstrator of its reusable hypersonic propulsion system. As that rarest of beasts, a powerplant concept combining the air-breathing efficiency of a jet engine with the power and vacuum operating capability of a rocket, the SABRE (Synergistic Air-Breathing Rocket Engine) cycle is a potential game changer ...

http://aviationweek.com/technology/reaction-engines-refines-hypersonic-engine-demonstrator-plan

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Offline FighterJock

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Re: Skylon Spaceplane
« Reply #174 on: December 12, 2016, 08:45:25 am »
Interesting link bobbymike,  I always like to keep up to date with all things Skylon related.

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Re: Skylon Spaceplane
« Reply #175 on: December 12, 2016, 03:29:36 pm »
...
"There are many disbelievers in
stealth, more than a few of them truly technically ignorant and proud of it." Sherm Mullin, Skunk Works

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Re: Skylon Spaceplane
« Reply #176 on: December 15, 2016, 10:05:22 am »
...

Yep, do air-launch before attempting SSO, it's a no-brainer that the industry loves to forget. Personally I think the key problem has always been that SSO sparks more romanticism in the designers. This is best countered with fancy graphics, because two sleek shiny things parting company look more romantic that one sleek shiny thing posing for the artist. And getting the big one off the shelf is a great way to look like you are down-to-earth cost cutting.
Cheers.

Offline Zootycoon

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Re: Skylon Spaceplane
« Reply #177 on: December 15, 2016, 03:26:13 pm »
A Two stage to orbit is a non ambitious compromise which inflates costs and drives down payload.

Getting to orbit is far more about velocity than altitude because the in the energy term it's squared. Hence an off the shelf first stage i.e subsonic is utterly pointless as constrains the payload stage enormously. The Tristar Pegasus has a tiny payload and orbital mass fraction of the complete aircraft/rocket is no better than vertical lifting rocket. It only exists because of whole load surplus cheap Mx motors becoming available. The stratolaunch is now stillborn because it never made sense even if they had/do fly it.

The AFRL is looking for a high speed (Mach 6) sabre based first stage to launch an expendable second stage. This approach may be quite politically motivated as one of the senior guys in that organisation only a few years ago declared that SSO would not be possible for twenty or more years.

Good luck to Reaction Engines for  getting Skylon together as an SSO

Offline Byeman

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Re: Skylon Spaceplane
« Reply #178 on: December 16, 2016, 09:08:56 pm »
1.  A Two stage to orbit is a non ambitious compromise which inflates costs and drives down payload.

2.  Getting to orbit is far more about velocity than altitude because the in the energy term it's squared.

3. Hence an off the shelf first stage i.e subsonic is utterly pointless as constrains the payload stage enormously. The Tristar Pegasus has a tiny payload and orbital mass fraction of the complete aircraft/rocket is no better than vertical lifting rocket.

4.   It only exists because of whole load surplus cheap Mx motors becoming available.



1.  A statement unsupported by physics and reality

2.  Air launch benefits Pegasus via lower air density and not launch altitude. 

3.  It isn't utterly pointless.  It is that you don't utterly understand the benefits or the physics, like multiple launch site, multiple azimuths from single launch sites and that mass to orbit is not the primary consideration.  If mass to orbit was a primary consideration, then SpaceX would not be using a returnable first stage.  And like the Falcon 9, Pegasus has a reusable first stage.

4.  MX has nothing to do with Pegasus.  Pegasus existed before MX was going to be decommissioned.  Pegasus does not use any motors that were used by or related to the MX.
« Last Edit: December 16, 2016, 09:20:57 pm by Byeman »

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Re: Skylon Spaceplane
« Reply #179 on: December 16, 2016, 09:31:06 pm »

1.  The Pegasus 1 is a whole load of surplus /obsolete components cobbled together, i.e. Mx missile rocket motors, an old /unwanted airliner, etc.  If all the bits are free or bargin basement prices it's easy to make the business case. Its a very desperate solution with an orbital mass fraction of 0.2% of the runway take off weight.


2.  Talking of which, the Space Shuttle sitting on top of a 747 may have looked cool but this doesn't translate to a practical launch solution, remember when on the 747 it had no fuel or payload. The high centre of gravity of the combination had to be reacted by the 747 Nose Landing Gear when braking (the design case will be the max energy RTO).  Any commercial airliner is designed to be just about strong enough to perform its intended task and doesn't have spare margins. So to estimate the mass of a piggy back orbital vehicle take the normal passenger payload weight and divide it by the increased  moment arm due to extra cg height. My guess is A340, without massive structural modifications, would be able to carry, piggyback, a 20 ton orbiter max. Skylon is designed to have a max take off weight of about 280 tons.


1.  You really don't know what you are talking about.  The Pegasus uses motors that were specifically design for it.  Hence, they were not surplus nor obsolete.

2.  Your point is meaningless because there has to be structural modifications to carry anything piggyback on top of an aircraft.  The shuttle orbiter weighed about 110 tons. 

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Re: Skylon Spaceplane
« Reply #180 on: December 17, 2016, 12:11:37 am »
The space shuttle orbiter empty weight is 68 ton, which is the weight it would have been on the back of 747. I believe, while in flight  the combination was significant limited in both airspeed and max altitude as well;- this would further reduce the orbital energy input. 110 Ton is an orbiter with an integrated payload and is well beyond the payload of a 747;- any claim that the structural modification to mount it on its back could extend to that level basic wing root bending enhancement is unsupported by physics or realty.

As for your assertion relating to air density this only effects nozzle expansion ratio optimisation which is a second order effect on payload mass fraction. I would welcome you to publish the physics which shows that kinetic energy is not the sole dominant factor in getting a payload into orbit. 

Sure a two stage to orbit concept gives the ability for launch point selection but that wasn't the point, a single stage such as Skylon can offer the same flexibility.

Pegasus's Tristar was the last one flying in the world because they deliberately chose to control costs by using obsolete equipment. Nothing wrong with that but is show how marginal the business case is.


Offline steelpillow

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Re: Skylon Spaceplane
« Reply #181 on: December 17, 2016, 02:51:29 am »
I would welcome you to publish the physics which shows that kinetic energy is not the sole dominant factor in getting a payload into orbit. 
Of course this has always been the prime rationale for multi-stage launch, as was first realised in the mid-twentieth century and ever since then multi-stage has been the only possible way to attain orbit. That Zootycon is using the same rationale to try and justify SSO technology over multi-stage is - what, ironic perhaps? SABRE makes it technically possible but it doesn't change the proven economic advantage of multi-stage.

Second-best is a subsonic COTS (commercial-off-the-shelf) mothership with SABRE upper stage. As British Aerospace found donkeys years ago (and contrary to Zootycon's dreams), this is the cheapest and lowest-risk orbiter to develop.  And as Pegasus has amply demonstrated, a conventional mothership brings operational flexibilities which have high value in themselves.

Better is a suborbital SABRE-powered mothership. It might even borrow a trick from the Shuttle, with the orbiter's conventional rocket engine providing boost for takeoff. But that's two specialist craft, with twice the development cost and the risk squared. Let's do it the easy way first.

You don't even need SABRE. An atmospheric mothership, suborbital rocket second stage and rocket orbiter would have been viable fifty years ago - think B52 plus X-15 with disposable orbiter hung beneath, then refine. But that refining triples the development cost, so nobody ever dared go there.

Exercise for the student: Taking the Virgin Galactic two-stage suborbital launch system as a starting point, how is it best developed to give orbital capability? SABRE for the mothership? SABRE for the second stage? A new rocket third stage? Richard Branson would love to know!

But if you are willing to set aside orbital flight for now then, whether or not you believe that SSO will ultimately triumph, a sub-orbital Skylon is an obvious next step.
« Last Edit: December 19, 2016, 10:50:47 am by steelpillow »
Cheers.

Offline SteveO

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Re: Skylon Spaceplane
« Reply #182 on: December 18, 2016, 09:21:26 am »
Hmmm... not much to look at anymore on the new website https://www.reactionengines.co.uk

Hopefully the lack of documents, images and videos indicates real world progress is being made!

Offline mz

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Re: Skylon Spaceplane
« Reply #183 on: December 18, 2016, 01:28:40 pm »
The space shuttle orbiter empty weight is 68 ton, which is the weight it would have been on the back of 747. I believe, while in flight  the combination was significant limited in both airspeed and max altitude as well;- this would further reduce the orbital energy input. 110 Ton is an orbiter with an integrated payload and is well beyond the payload of a 747;- any claim that the structural modification to mount it on its back could extend to that level basic wing root bending enhancement is unsupported by physics or realty.

As for your assertion relating to air density this only effects nozzle expansion ratio optimisation which is a second order effect on payload mass fraction. I would welcome you to publish the physics which shows that kinetic energy is not the sole dominant factor in getting a payload into orbit. 

Sure a two stage to orbit concept gives the ability for launch point selection but that wasn't the point, a single stage such as Skylon can offer the same flexibility.

Pegasus's Tristar was the last one flying in the world because they deliberately chose to control costs by using obsolete equipment. Nothing wrong with that but is show how marginal the business case is.

initial mass / final mass = exp ( delta vee / effective exhaust velocity)

The effective exhaust velocity can be made significantly higher for lower ambient pressures. Don't have info on 20% sea level air pressure, or whatever Pegasus is launched at, but here's some back of the envelope:

For example the SpaceX Merlin engine has a nozzle extension on the vacuum version.

Merlin 1C with sea level nozzle
Sea level: 350 kN, 275 s
Vacuum: 400 kN, 304 s

Merlin 1C with vacuum nozzle extension
Vacuum: 411 kN, 342 s

For example if you need 6 km/s of stage delta vee, with a normal ISP of 3 km/s you need e^(6/3) = e^2 = 7.4 mass ratio.
While with the air launch ISP 3.4 km/s you only need a 5.8 mass ratio.

You could downsize the first stage and leave out some engines, to save on cost per launch etc...

Offline Byeman

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Re: Skylon Spaceplane
« Reply #184 on: December 19, 2016, 08:52:17 am »
The space shuttle orbiter empty weight is 68 ton, which is the weight it would have been on the back of 747. I believe, while in flight  the combination was significant limited in both airspeed and max altitude as well;- this would further reduce the orbital energy input. 110 Ton is an orbiter with an integrated payload and is well beyond the payload of a 747;- any claim that the structural modification to mount it on its back could extend to that level basic wing root bending enhancement is unsupported by physics or realty.

2.  As for your assertion relating to air density this only effects nozzle expansion ratio optimisation which is a second order effect on payload mass fraction.

3.   I would welcome you to publish the physics which shows that kinetic energy is not the sole dominant factor in getting a payload into orbit. 



The fact that you are using wrong data just shows that the rest of your posts are suspect and you don't know what you are talking about. I make no "claims", I am only stating facts.

1.  When the shuttle orbiter landed at Edwards AFB and was ferried back to KSC, it was not empty, it still had some fluids onboard and payload.  And if the payload was a Spacelab, it was a full up payload. 
Here is a document covering the first 91 missions and it lists the ferry weights.  One was almost 230k pounds (i.e. 115 tons)

2.  Just as your assertion about  "combination was significant limited in both airspeed and max altitude as well;- this would further reduce the orbital energy input.".  Air launch is not about energy input.  Airspeed and altitude at launch figure little into the deltaV required. 
And as for my point on air density,  it is not an assertion on  nozzle expansion.  The benefit from air launch due to lower air density is less drag and dynamic pressure. 

3.  Never made any post that does not say otherwise.  However, there are other considerations and trades that affect what it costs to provide the kinetic energy.   
« Last Edit: December 24, 2016, 12:26:49 pm by Byeman »

Offline steelpillow

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Re: Skylon Spaceplane
« Reply #185 on: December 19, 2016, 10:57:49 am »
Hmmm... not much to look at anymore on the new website https://www.reactionengines.co.uk

Hopefully the lack of documents, images and videos indicates real world progress is being made!

Hedging their bets now:
"SABRE class engines are applicable in both multi-stage and single-stage architectures."
https://www.reactionengines.co.uk/vehicles/
Cheers.

Offline Ian33

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Re: Skylon Spaceplane
« Reply #186 on: December 19, 2016, 12:46:52 pm »
Hmmm... not much to look at anymore on the new website https://www.reactionengines.co.uk

Hopefully the lack of documents, images and videos indicates real world progress is being made!

Hedging their bets now:
"SABRE class engines are applicable in both multi-stage and single-stage architectures."
https://www.reactionengines.co.uk/vehicles/

No, not hedging their bets, fully realising the potential for small, bomber sized version as well as they big boys full sized monster to take payload to orbit.  I fully expect to see a little clip mid to late 2017 of such power plants demonstrated.
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Offline steelpillow

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Re: Skylon Spaceplane
« Reply #187 on: December 20, 2016, 02:58:21 pm »
...fully realising the potential for small, bomber sized version as well as they big boys full sized monster to take payload to orbit.
That's what I said, hedging their bets. :)
Cheers.

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Online bobbymike

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Offline Archibald

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Re: Skylon Spaceplane
« Reply #190 on: February 23, 2017, 11:33:20 pm »
Skylon on backburner until the 2030s. Et merde !!  :-\
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Offline Flyaway

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Re: Skylon Spaceplane
« Reply #191 on: May 04, 2017, 07:20:29 am »
Reaction Engines begins construction of UK rocket engine test facility

Reaction Engines Ltd. today began construction of a new engine test facility where it plans to undertake the first ground based demonstration of its revolutionary SABRE™ air-breathing rocket engine.

The test facility at Westcott, Buckinghamshire, UK  will enable Reaction Engines to test critical subsystems along with the testing of a SABRE engine core, which will commence in 2020.

The project represents a substantial investment for Reaction Engines, which will consist of a multi-purpose propulsion test stand designed to accommodate various test engine configurations, an assembly building, workshops, offices and control room.  The location of workshops and other support facilities alongside the test stand will enable configuration changes to the engine to take place at the site, reducing the down time between testing phases and accelerating the development programme of the SABRE engine.

To mark the start of construction, Mark Thomas, CEO, Reaction Engines undertook a ground breaking ceremony with Franco Ongaro, Director of Technology, Engineering and Quality, European Space Agency (ESA); Dr. Chris Castelli, Director, Programmes, UK Space Agency and Richard Harrington, CEO, Buckinghamshire Thames Valley LEP.

Mark Thomas, CEO, Reaction Engines said:

“This is another exciting step forward in development of Reaction Engines’ SABRE engine and a visible demonstration of the UK’s commitment to the programme.  I look forward to seeing this unique facility take shape and commencing our core engine testing, which will be a defining moment for aerospace.”

Franco Ongaro, Director of Technology, Engineering and Quality, ESA said:

“The opening of this new test facility at Westcott Today marks an historical moment for the European Aerospace industry and for the UK research and development in rocket propulsion. This facility will enable the ground test of the SABRE engine cycle, opening the way to the first flight tests, and to a new era. The European Space Agency is proud of this partnership with industry and the UK Space Agency, to which we bring our technical competence, which has supported the SABRE development to this stage, and we are confident, to its future flight success.”

The construction of the SABRE engine test facility is a significant milestone. The company has already successfully undertaken testing of the engine’s pre-cooler and thrust chamber technologies, and will undertake further ground-based high-temperature testing of the pre-cooler early in 2018.

The test facility is located in the Westcott Venture Park, a location with a strong history of rocket propulsion research, having been used to test various UK rocket projects since 1946, including the Blue Streak and Black Arrow programmes. In 2016 the UK Space Agency selected Westcott as the UK’s National Space Propulsion Test Facility and the site is now home to a number of space propulsion and satellite technology companies.

https://www.reactionengines.co.uk/reaction-engines-begins-construction-uk-rocket-engine-test-facility/

Offline FighterJock

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Re: Skylon Spaceplane
« Reply #192 on: May 04, 2017, 08:09:00 am »
That is brilliant news for Reaction Engines.   B)

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Re: Skylon Spaceplane
« Reply #193 on: May 04, 2017, 08:47:52 am »
Quote
Reaction Engines is proud to announce ground is now broken on our multi-£M #SABRETF1 core engine test facility @WestcottVP

Pictures on the link below.

https://mobile.twitter.com/ReactionEngines/status/860147329260822528

Offline Flyaway

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Re: Skylon Spaceplane
« Reply #194 on: May 10, 2017, 03:08:07 am »


Quote
Published on 8 May 2017

Animation of Reaction Engines SABRE TF1 test facility at Westcott Venture Park near Aylesbury.