A low cost, all European, manned launcher.

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RGClark

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This is in reference to an argument attached below that the Ariane 5 core stage
can be SSTO with 3 Vulcain engines.


The most important accomplishment of SpaceX may turn out to be they showed in
such stark terms the savings possible when launchers are privately financed:

SpaceX Might Be Able To Teach NASA A Lesson.
May 23, 2011
By Frank Morring, Jr.
Washington
“I think one would want to understand in some detail . . . why would it be
between four and 10 times more expensive for NASA to do this, especially at a
time when one of the issues facing NASA is how to develop the heavy-lift
launch vehicle within the budget profile that the committee has given it,”
Chyba says.
He cites an analysis contained in NASA’s report to Congress on the market for
commercial crew and cargo services to LEO that found it would cost NASA
between $1.7 billion and $4 billion to do the same Falcon-9 development that
cost SpaceX $390 million. In its analysis, which contained no estimates for
the future cost of commercial transportation services to the International
Space Station (ISS) beyond those already under contract, NASA says it had
“verified” those SpaceX cost figures.
For comparison, agency experts used the NASA-Air Force Cost Model—“a
parametric cost-estimating tool with a historical database of over 130 NASA
and Air Force spaceflight hardware projects”—to generate estimates of what it
would cost the civil space agency to match the SpaceX accomplishment. Using
the “traditional NASA approach,” the agency analysts found the cost would be
$4 billion. That would drop to $1.7 billion with different assumptions
representative of “a more commercial development approach,” NASA says.
http://www.aviationweek.com/aw/generic/story_generic.jsp?channel=awst&id=news/awst/2011/05/23/AW_05_23_2011_p36-324881.xml

The SpaceX experience of developing a launcher in the Falcon 9 at 1/10th the
cost of a government financed one also holds for the crew capsule development
costs since the Dragon capsule cost about $300 million to develop while the
Orion costs several billion and still counting. So it can't be said this cost
saving is just due to the Falcon 9 being, so far, unmanned.
Speaking about Orion and billions of dollars, I read an article about plans
to use the Orion on the Ariane 5 to get a European manned spaceflight
capability:

French govt study backs Orion Ariane 5 launch.
By Rob Coppinger
on January 8, 2010 4:45 PM
http://www.flightglobal.com/blogs/hyperbola/2010/01/french.html

This would cost several billion dollars to man-rate the Ariane 5. I have to
believe the solid rocket boosters, which can not be shut down when started,
play a significant role in that high cost. The article mentions also the
core stage would have to be strengthened. But such strengthening is based on
it having to support a 20 mT Orion capsule and a 20 mT upper stage which
wouldn't be used with a much smaller capsule such as the Dragon, at a dry mass
of about 4 mT.
Note also that quite likely an even smaller manned capsule could be designed
at about a 2 mT dry mass to carry a 3 man crew, which given its half size
compared to the Dragon, might cost in the range of only $150 million to
develop as privately financed. It's hard to imagine that private investment
could not be found to finance such a capsule development when it could lead to
a manned European space capability.
In regards to the costs of a privately financed SSTO version of the Ariane
launcher we might make a comparison to the Falcon 9. It cost about $300
million to develop and this includes both the structure and engines, the
engines making up the largest share of the development cost of a launcher. But
for the SSTO Ariane both engine and structure are already developed and it's
only a single stage instead of the two stages of the Falcon 9. You would have
the development cost of adding 2 additional engines and of the new avionics,
but again I have to be believe the development cost would once again be less
than the SpaceX development cost of the Falcon 9 if privately financed.

I also read that the ESA is attempting to decide whether to upgrade the
Ariane 5 or move to a Next Generation Launcher(NGL):

Ariane rocket aims to pick up the pace.
25 June 2011 Last updated at 06:39 ET
http://www.bbc.co.uk/news/science-environment-13911901

Thu, 9 February, 2012
France, Germany To Establish Working Group To Resolve Ariane 5 Differences.
By Peter B. de Selding
http://www.spacenews.com/policy/120209-france-germany-resolve-ariane5-differences.html

If the NGL is chosen then a quite expensive new large engine development
would have to be made, and the launcher might not enter service until 2025. In
contrast the SSTO-Ariane, given that the engine and stage already exist, a
prototype probably could be ready within 1 to 2 years, and moreover by using a
second stage it could also be used to launch the medium sized payloads.

So the SSTO-Ariane would solve the twin problems at low cost of providing
Europe with a manned spaceflight capability and giving it a lower cost medium
lift capability.


Bob Clark



======================================================================
Newsgroups: sci.space.policy, sci.astro, sci.physics, sci.space.history, rec.arts.sf.science
From: Robert Clark
Date: Thu, 8 Sep 2011 13:56:20 -0700 (PDT)
Subject: Re: A kerosene-fueled X-33 as a single stage to orbit vehicle.

I saw this discussed on a space oriented forum:

WSJ: Europe Ends Independent Pursuit of Manned Space Travel.
"LE BOURGET, France—Europe appears to have abandoned all hope of
independently pursuing human space exploration, even as the region's
politicians and aerospace industry leaders complain about shrinking
U.S. commitment to various space ventures.
"After years of sitting on the fence regarding a separate, pan-
European manned space program, comments by senior government and
industry officials at the Paris Air Show here underscore that budget
pressures and other shifting priorities have effectively killed that
longtime dream."
http://www.orbiter-forum.com/showthread.php?t=23006

In this post I discussed getting a SSTO by replacing the Vulcain
engine on the Ariane 5 core with a SSME:

Newsgroups: sci.space.policy, sci.astro, sci.physics, sci.space.history
From: Robert Clark
Date: Wed, 23 Feb 2011 10:14:42 -0800 (PST)
Subject: Re: Some proposals for low cost heavy lift launchers.
http://groups.google.com/group/sci.physics/msg/e1736e7586cc269f?hl=en

However, in point of fact Europe can produce a manned launch vehicle
from currently *existing*, European components. This will consist of
the Ariane 5 and three Vulcain engines. The calculations below use the
Ariane 5 generic "G" version. You might need to add another Vulcain
for the larger evolution "E" version of the Ariane 5 core.
In a following post I'll also show that the Hermes spaceplane also
can become a SSTO by filling the entire fuselage aft of the cockpit
with hydrocarbon propellant.
The impetus for trying the calculation for a Ariane 5 core based SSTO
using Vulcains instead of the SSME was from a report by SpaceX that
you could get the same performance from a planned heavy lift first
stage using a lower performance Merlin 2 compared to the high
performance RS-84 engine. The reason was the lower Isp of the Merlin
was made up for by its lower weight.

THIS IS A VERY IMPORTANT FACT BECAUSE WHAT IT MEANS IS THAT YOU DON'T
NEED THE HIGH PERFORMANCE ENGINES TO GET THE SSTO. YOU CAN USE ENGINES
OF LOWER CHAMBER PRESSURE AND SIMPLER COMBUSTION CYCLES, SUCH AS THE
VULCAIN WITH A CA. 100 BAR COMBUSTION PRESSURE AND A GAS GENERATOR
CYCLE. THIS MEANS THE ENGINES ARE CHEAPER, EASIER TO MAKE REUSABLE,
REQUIRE LESS ROUTINE MAINTENANCE, AND CAN LAST FOR MANY RESTARTS.

In the discussion of the Ariane/Vulcain SSTO below, I note you can
get a prototype, test vehicle quite quickly since the components are
already existing. To improve the payload though you would want to use
altitude compensation on the Vulcains. In a following post I'll
discuss some methods of altitude compensation.
In regards to achieving this at low cost, I think the most important
accomplishment of SpaceX might turn out to be that they showed in
stark terms that privately financed spacecraft, both launchers and
crew capsules, can be accomplished at 1/10th the developmental cost of
government financed ones. Imagine a manned, reusable orbital launcher,
for example, instead of costing, say, $3 billion, only costing $300
million to develop.
Here's how you can get an all European manned SSTO using the Ariane 5
core stage but with Vulcain engines this time. Note that this is one
that can be produced from currently existing components, aside from
the capsule, so at least an unmanned prototype vehicle can be
manufactured and tested in the short term and at lowered development
cost.
We'll use three Vulcain 2's instead of the 1 normally used with the
Ariane 5 core stage. There are varying specifications given on the
Vulcain 2 depending on the source. I'll use the Astronautix site:

Vulcain 2.
http://www.astronautix.com/engines/vulcain2.htm

From the sea level thrust given there, using three Vulcain 2's will
give us one engine out capability. The weight is given as 1,800 kg. So
adding on two will take the dry mass from 12 mT to 15.6 mT.
To calculate the delta-V achieved I'll use the idea again to just use
the vacuum Isp, but adding the loss due to back pressure onto the
delta-V required for orbit, as I discussed previously. However, here
for hydrogen fuel which has higher gravity loss, I'll use a higher
required delta-V of 9,400 m/s when you add on the back pressure loss.
With the vacuum Isp given for the Vulcain 2 of 434 s, we get a payload
of 3.8 mT:

434*9.8ln(1+158/(15.6+3.8)) = 9,412 m/s.

Note this is just using the standard nozzle Isp for the Vulcain, no
altitude compensation. So this could be tested, like, tomorrow.
However, for a SSTO you definitely want to use altitude compensation.
Using engine performance programs such as ProPEP we can calculate that
using long nozzles, you can get a vacuum Isp of 470 s for this engine.
As a point of comparison of how high an Isp you can get even with a
low chamber pressure engine as long as you have a long nozzle, or
equivalent, note that the RL10-B2 with a ca. 250 to 1 area ratio, and
only a ca. 40 bar chamber pressure, gets a 465 s vacuum Isp. So we'll
assume we can get a comparable Isp by using altitude compensation.
This allows us to get payload of 8 mT:

470*9.8ln(1+158/(15.6+8) = 9,400 m/s.

This allows us to add a Dragon-sized capsule and also the reentry and
landing systems to make it reusable.


Bob Clark
======================================================================
 

Hobbes

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I wonder where your figures are from.
http://en.wikipedia.org/wiki/Ariane_5 has the first stage dry mass at 15t and fueled mass at 170t, and Isp at 431 s.
That results in 19,5 tons of empty mass, so 0,9 tons of payload to orbit (assuming your 9400 m/s).
 
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RGClark

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Hobbes said:
I wonder where your figures are from.
http://en.wikipedia.org/wiki/Ariane_5 has the first stage dry mass at 15t and fueled mass at 170t, and Isp at 431 s.
That results in 19,5 tons of empty mass, so 0,9 tons of payload to orbit (assuming your 9400 m/s).

As mentioned on the Wikipedia site, there are several variations of the Ariane 5. I was using the specifications for the "G" version. The specifications for this are given here:

Ariane 5.
http://www.spacelaunchreport.com/ariane5.html

There is a slightly larger version called the "E". For this you may need to add one more additional engine to retain engine out capability.
I've also seen several quoted values for the vacuum Isp of the Vulcain 2. For instance, the SpaceLaunchReport site gives it as 431.2 s. However, the Astronautix site gives it as 434 s:

Vulcain 2.
http://www.astronautix.com/engines/vulcain2.htm

I took it optimistically as 434 s.

Bob Clark
 

Byeman

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Not a valid concept.
A. Ariane is a govt developed vehicle. Spacex principles can not be applied to it.
B. It and other vehicle is not an SSTO, no matter how many times and forums you post it.




Why don't you contribute something that fits the spirit of this website , instead of polluting another forum to post your non feasible ideas.
 
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Note to moderator:
this topic is speculative so it would be fine to move it to the "Theoretical and Speculative Projects" sub-forum.

Bob Clark
 

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Either there is a problem with some assumptions, or Ariane 5 is much farther from ideal performance then you think. I checked the numbers for baseline Ariane 5G with 9,500 kg load and got delta-V of 12,000 m/s. This calculation was based on vacuum performance for all engines and thrust profile split into 3 stages: with boosters, EPC after boosters separate and EPS.
You thoughts?
 
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AdamF said:
Either there is a problem with some assumptions, or Ariane 5 is much farther from ideal performance then you think. I checked the numbers for baseline Ariane 5G with 9,500 kg load and got delta-V of 12,000 m/s. This calculation was based on vacuum performance for all engines and thrust profile split into 3 stages: with boosters, EPC after boosters separate and EPS.
You thoughts?

Not quite clear what you are asking. Are you saying using the full "G" version results in a launcher very far from the 20 mT LEO capability of the current "E" version? O.K. The SpaceLaunchReport page on the Ariane 5G also gives its LEO payload as 9.5 mt.
I was suggesting using just the core stage for a manned vehicle because of what's stated in this article from Jan., 2010:

French govt study backs Orion Ariane 5 launch.
By Rob Coppinger
on January 8, 2010 4:45 PM
http://www.flightglobal.com/blogs/hyperbola/2010/01/french.html

that it would take billions to man-rate the full Ariane 5. But then according to a later article from June, 2011 the plan to make a manned European launcher was cancelled because of the high costs:

WSJ: Europe Ends Independent Pursuit of Manned Space Travel.
"LE BOURGET, France—Europe appears to have abandoned all hope of
independently pursuing human space exploration, even as the region's
politicians and aerospace industry leaders complain about shrinking
U.S. commitment to various space ventures.
"After years of sitting on the fence regarding a separate, pan-
European manned space program, comments by senior government and
industry officials at the Paris Air Show here underscore that budget
pressures and other shifting priorities have effectively killed that
longtime dream."
http://www.orbiter-forum.com/showthread.php?t=23006

But note that earlier plan was using the heavy Orion capsule which would require the full Ariane 5 with the solid rocket boosters. Presumably it would be easier to man-rate if you only used the core stage albeit with 2 added Vulcain engines.
This of course would require you to carry a much smaller capsule than the Orion. It should be possible to get a smaller capsule at half the size of the SpaceX Dragon, so to a ca. 2 mT dry mass, to carry only 3 man crew instead of the 7 of the Dragon. My calculation added on 2 extra Vulcain 2 engines to the "G" core stage only and showed it should be able to lift a capsule this size.
BTW, European members of this forum might prefer this site for the specifications on the Ariane:

European Space Launch Vehicles.
http://www.b14643.de/Spacerockets_1/West_Europe/West_Europe.htm

I've found their numbers to be accurate in the past.


Bob Clark
 
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Hobbes said:
As far as I can see, the rocket equation does not account for atmospheric drag.

This site takes that and other effects into account:
http://www.silverbirdastronautics.com/LVperform.html

Yes, I have used that site to give confidence that my payload numbers are reasonable. A complaint against this site though is that it gives a range of values for the payload centered around some estimate.


Bob Clark
 

Michel Van

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The Irony off all this is: Ariane 5 was original planed as manned Launcher for Hermes spaceglider.


On SSTO Ariane 5 core stage with 3xVulcan II
i have my problems with it: the Fuel consumption of three engine
that, you guess it three time higher.
So reduce the burntime to 1/3 of Normal Ariane 5 core stage from 540 to 180 seconds
i have my doubts if the payload reach orbit even if after burnout, the empty stage is drop and payload keep the impulse energy from launch and use his engine to get in orbit
although the french Diamant launcher use similar flight profile
were the third stage rise, thanks of impuls energy from 1&2 stage for 313 seconds, before it's engine fires the payload into orbit.
http://www.capcomespace.net/dossiers/espace_europeen/ariane/espace_francais/diamantA%20plan%20de%20vol.jpg


Escape from this dilemma ?
try the use one SSME, the engine thrust can be throttled from 109% to 67%, means reduction on Fuel consumption
So longer burntime, more impuls energy into payload to reach Orbit
 

Hobbes

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RGClark said:
AdamF said:
Either there is a problem with some assumptions, or Ariane 5 is much farther from ideal performance then you think. I checked the numbers for baseline Ariane 5G with 9,500 kg load and got delta-V of 12,000 m/s. This calculation was based on vacuum performance for all engines and thrust profile split into 3 stages: with boosters, EPC after boosters separate and EPS.
You thoughts?

Not quite clear what you are asking. Are you saying using the full "G" version results in a launcher very far from the 20 mT LEO capability of the current "E" version?

He's saying that putting the real-world numbers for the Ariane 5G into the rocket equation results in way more delta-V than you'd expect. This is because the rocket equation assumes a vacuum.
His results suggest that if you want to use the rocket equation, you'll need to use a delta-V of 12000 m/s instead of the 9400 you've been using.
Doing that, with Isp=434s and total weight is 170 tons results in an empty weight of 10.13 tons, which means an Ariane 5G core cannot achieve orbit with Vulcain engines.
 
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Michel Van said:
The Irony off all this is: Ariane 5 was original planed as manned Launcher for Hermes spaceglider.

On SSTO Ariane 5 core stage with 3xVulcan II
i have my problems with it: the Fuel consumption of three engine
that, you guess it three time higher.
So reduce the burntime to 1/3 of Normal Ariane 5 core stage from 540 to 180 seconds
i have my doubts if the payload reach orbit even if after burnout, the empty stage is drop and payload keep the impulse energy from launch and use his engine to get in orbit
although the french Diamant launcher use similar flight profile
were the third stage rise, thanks of impuls energy from 1&2 stage for 313 seconds, before it's engine fires the payload into orbit.
http://www.capcomespace.net/dossiers/espace_europeen/ariane/espace_francais/diamantA%20plan%20de%20vol.jpg

Escape from this dilemma ?
try the use one SSME, the engine thrust can be throttled from 109% to 67%, means reduction on Fuel consumption
So longer burntime, more impuls energy into payload to reach Orbit

A fair point. In studies on SSTO's usually it is planned to throttle down the engines higher up in the trajectory or shut down some of the engines. This is because the total thrust of the engines has to be above the gross mass which will be 10 or more times that of the dry mass for a SSTO. So near the end of the flight when most of the propellant is burned off, the thrust will be above 10 times the vehicle weight which will give a acceleration of above 10 g's.
For the Vulcain 2, I haven't seen that it is throttleable. So you could shut down the two outer engines higher up in the flight.

Bob Clark
 
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Hobbes said:
RGClark said:
AdamF said:
Either there is a problem with some assumptions, or Ariane 5 is much farther from ideal performance then you think. I checked the numbers for baseline Ariane 5G with 9,500 kg load and got delta-V of 12,000 m/s. This calculation was based on vacuum performance for all engines and thrust profile split into 3 stages: with boosters, EPC after boosters separate and EPS.
You thoughts?

Not quite clear what you are asking. Are you saying using the full "G" version results in a launcher very far from the 20 mT LEO capability of the current "E" version?

He's saying that putting the real-world numbers for the Ariane 5G into the rocket equation results in way more delta-V than you'd expect. This is because the rocket equation assumes a vacuum.
His results suggest that if you want to use the rocket equation, you'll need to use a delta-V of 12000 m/s instead of the 9400 you've been using.
Doing that, with Isp=434s and total weight is 170 tons results in an empty weight of 10.13 tons, which means an Ariane 5G core cannot achieve orbit with Vulcain engines.

Thanks for explaining what was meant. A delta-V of 12,000 m/s is far too high just to achieve LEO. That's about what is needed to achieve Earth escape velocity. Usually to find the delta-V to reach low Earth orbit, you add on only about 1.5 to 2 km/s for gravity and air drag to the 7.8 km/s speed for Earth orbit: Delta-v budget.
I think the main explanation for the discrepancy is that 9.5 mT payload number for the Ariane 5G on the SpaceLaunchReport page is for a sun-synchronous orbit(SSO). This is higher than usual for generic LEO, about 100 km to 200 km, at up to 800 km altitude. The higher altitude requires higher delta-V to reach.
But more importantly is the plane change required for SSO, at about a 90° angle. Large plane changes like this require large amounts of delta-V to accomplish.
Note the Astronautix page on the Ariane 5G gives the payload to LEO as 16,000 kg, but even this is for an altitude of 407 km and an inclination 51.60°, a rather high plane change for an equatorial launched Ariane.
And the "Gunter's Space Page" gives the LEO payload as 18,000 kg:

Ariane-5G.
http://space.skyrocket.de/doc_lau_det/ariane-5g.htm


Bob Clark
 

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RGClark said:
But more importantly is the plane change required for SSO, at about a 90° angle. Large plane changes like this require large amounts of delta-V to accomplish.
Note the Astronautix page on the Ariane 5G gives the payload to LEO as 16,000 kg, but even this is for an altitude of 407 km and an inclination 51.60°, a rather high plane change for an equatorial launched Ariane.

See, you don't even know basic orbital mechanics, much less launch vehicle performance design.

There is no "plane change" needed for Ariane to launch into SSO or 51.6° inclination. Ariane can launch on an azimuth that puts it into the proper inclination. yes, there is a slight loss of performance since higher inclination launches do not get the full benefit of earth's rotation. But it is not due to plane changes like those required for launches from CCAFS into GSO.
 
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Byeman said:
RGClark said:
But more importantly is the plane change required for SSO, at about a 90° angle. Large plane changes like this require large amounts of delta-V to accomplish.
Note the Astronautix page on the Ariane 5G gives the payload to LEO as 16,000 kg, but even this is for an altitude of 407 km and an inclination 51.60°, a rather high plane change for an equatorial launched Ariane.

See, you don't even know basic orbital mechanics, much less launch vehicle performance design.

There is no "plane change" needed for Ariane to launch into SSO or 51.6° inclination. Ariane can launch on an azimuth that puts it into the proper inclination. yes, there is a slight loss of performance since higher inclination launches do not get the full benefit of earth's rotation. But it is not due to plane changes like those required for launches from CCAFS into GSO.

Thanks for the correction. You can put a satellite into a different orbital inclination than the one indicated by the latitude you're launching from without doing a plane change after reaching orbit. However, it still does require additional delta-V which explains the reduced payload.

Bob Clark
 

Byeman

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RGClark said:
Thanks for the correction. You can put a satellite into a different orbital inclination than the one indicated by the latitude you're launching from without doing a plane change after reaching orbit. However, it still does require additional delta-V which explains the reduced payload.

Bob Clark

Again, you don't know what you are talking about.

No, it does not require additional delta-V. The launch vehicle does not burn more propellant.
 
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Byeman said:
Again, you don't know what you are talking about.

No, it does not require additional delta-V. The launch vehicle does not burn more propellant.

If you can't make use of the Earth's rotational velocity by not launching eastward then the rocket itself has to provide that extra delta-V.

Bob Clark
 

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RGClark said:
Byeman said:
Again, you don't know what you are talking about.

No, it does not require additional delta-V. The launch vehicle does not burn more propellant.

If you can't make use of the Earth's rotational velocity by not launching eastward then the rocket itself has to provide that extra delta-V.

No, the rocket flies with less payload, not extra deltaV
 

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No.
The rocket has to attain orbital velocity. This is independent of the orbital inclination. When launching due East from the equator, it gets 463 m/s of delta-V for free from the Earth's rotation. When launching to a 51-degree orbit, it'll get (463*cos(51))=291 m/s, so the rocket's engines have to provide an additional 172 m/s of delta-V to achieve orbit.

The easiest way to do this is to reduce the payload.
 
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Hobbes said:
No.
The rocket has to attain orbital velocity. This is independent of the orbital inclination. When launching due East from the equator, it gets 463 m/s of delta-V for free from the Earth's rotation. When launching to a 51-degree orbit, it'll get (463*cos(51))=291 m/s, so the rocket's engines have to provide an additional 172 m/s of delta-V to achieve orbit. This means it'll have to carry more fuel. The net result is a reduced payload.

Thanks. That's illuminating a distinction between what the "delta-V" is that has to be achieved, from whatever source, to reach orbit, and the "delta-V" that has to be provided by the rocket. It is correct in the first sense to say the "delta-V" is going to be the same. But in the second use of the term the "delta-V" is going to be different.

Bob Clark
 

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But the important question should, why would you want to build an SSTO?
 
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mz said:
But the important question should, why would you want to build an SSTO?

Good point. It doesn't have to be a SSTO. I was arguing for using a much smaller capsule than the Orion for then you wouldn't need the full Ariane 5 launcher, with the two large strap on boosters, so it would be easier and cheaper to man-rate.
If you still give the Ariane 5G core stage two additional Vulcain 2's, then you can lift greater payload using an upper stage than with the SSTO version. You would need to include the mass of the interstage in this case to support the weight of the upper stage and payload, call it 1,000 kg for the interstage.
In the calculation I'll use the 15.6 mT dry mass I used before for the Ariane 5G with the two extra Vulcain 2's and again a 434 s Isp for the Vulcain 2. I'll get the specifications for the LH2/LOX upper stage also from the SpaceLaunchReport page on the Ariane 5, at a 19.4 mT gross mass, 14.9 mT propellant load, 4.5 mT dry mass, and 446 s Isp of the upper stage cryogenic engine. I also include in the calculation 1 mT for the interstage that will be in the first stage delta-V calculation only since it is jettisoned along with the first stage. Then you could lift ca. 10 mT to orbit:

434*9.81ln(1 + 158/(15.6 + 19.4 + 10 + 1)) + 446*9.81ln(1 + 14.9/(4.5 + 10)) = 9,434 m/s.

This could then loft a Dragon sized capsule. It could also loft the Boeing CST-100 capsule and the Sierra Nevada Dream Chaser since these are both planned to be launched by the Atlas V version without the side boosters, which has a ca. 10 mT LEO payload capability.
So this could compete for those launches of these manned spacecraft planned now only to be carried by either the Falcon 9 or Atlas V. This launcher again should have comparatively low development cost since the engines and stages are already developed and you would have only the development cost of adding on the two engines and the new avionics.
This option should be more palatable to the ESA since it avoids the controversial SSTO's. Of course at some point it would be realized, "Hmm, if we made the capsule half the size of those other ones to carry just three people then that first stage by itself could carry it, and we wouldn't have that extra expense of the upper stage ..."


Bob Clark
 
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RGClark

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The CST-100 crew capsule is largely privately financed by Boeing, though they have gotten some commercial crew development dollars from NASA as has SpaceX. This is a very important point that the CST-100 is primarily privately financed. I can guarantee you Boeing is not spending several billion dollars of their own money developing the CST-100 like what Orion is costing using government money. (Note to Boeing: come up with a better name for your capsule.)

My guess is that it's costing a few hundred million dollars tops, comparable to what the Dragon cost SpaceX to develop. Note this once again means a privately financed spacecraft can be developed for 1/10th the cost of a government financed one. That Boeing was able to do this just as SpaceX has done overwhelmingly implies this is valid as a general principle. Note this also strongly implies that the large launch providers such as Boeing can produce a launcher capable of manned flight as privately financed for 1/10th the cost of the billion dollar estimates given for such launchers, so in the few hundred million dollar range, just as SpaceX has done with the Falcon 9.

This also strongly implies the same is true for the space programs in other countries. In this thread I'm arguing the ESA could produce a manned launcher for a few hundred million dollars if privately financed. The objection was raised the same kind of cost savings SpaceX made wouldn't apply in this case.

However, the ESA is a government organization which supplies government finances from the ESA member countries to the private companies that build the Ariane 5 launcher. Then all that would be required is that the ESA also, like NASA, make a proposal of European aerospace companies to privately develop launchers and spacecraft, perhaps with some amount of seed money as NASA is doing, and that the ESA would make a commitment to purchase such launchers and spacecraft even if such launchers undercut the prices of the Ariane 5.

Note that Boeing originally lost out to Lockheed to build the Orion capsule. But with the CST-100 it will be able to make more manned launches to orbit, at an earlier start date, and at much reduced cost than the Orion. And in fact, several different companies will now have the opportunity to offer manned launch services to NASA.

The same would be true of the European aerospace companies, to allow several different companies to operate offering launch and spacecraft services to the ESA, not just EADS Astrium with the Ariane 5. This will have the effect of increasing the European space industry not reducing it.


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RGClark said:
However, the ESA is a government organization which supplies government finances from the ESA member countries to the private companies that build the Ariane 5 launcher. Then all that would be required is that the ESA also, like NASA, make a proposal of European aerospace companies to privately develop launchers and spacecraft, perhaps with some amount of seed money as NASA is doing, and that the ESA would make a commitment to purchase such launchers and spacecraft even if such launchers undercut the prices of the Ariane 5.

Again, you show the lack of knowledge and don't understand what is going on.

The money that gets supplied to ESA goes back to member countries in form of contracts with regard to efficency. They are not going to undercut Ariane. Also, there is no commercial launch site for other companies. Arianespace has a monopoly in Korou.
 
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ESA to Compete Next-Gen Launcher Ahead of Budget Talks.
Posted by Amy Svitak at 3/27/2012 7:56 AM CDT
In the meantime, ESA's Dordain is expected to seek proposals from industry next month for building a next-generation launcher that would bend the 19-nation agency's industrial participation rules and facilitate more competition among companies in an effort to lower development costs.
“I have a meeting with the launcher industry at the beginning of April and after that we shall issue the invitation to tender for getting proposals from industry on a next-generation launch vehicle based on requirements coming from a European customer base,” Dordain said.
ESA's current approach to procurement relies on member states to ante up funding every three years or so for specific development programs, leaving ESA to build the project while guaranteeing a 90-percent return on investment for participating countries in the form of industrial work share.
Last year an outside audit of Ariane 5 manufacturers found that unless European governments agreed to bend ESA's geographic return rules, the agency would be hard pressed to find savings with a new rocket development.
Dordain believes the shift in acquisition approach would indeed lower the cost to develop a new launcher, a figure that France and Germany say is expected to fall somewhere between €3-5 billion.


So it looks like the ESA is subject to the same inefficiencies as is NASA. Then likewise transitioning to a more commercial approach should cut costs as is the case with NASA.


Bob Clark
 

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The math aside, I am not sure whether I understand your arguments. You are proposing that a completely new launcher, built out of tested components, will be easier to man-rate than a tested launcher with proven track record.


What you are proposing is a completely new launcher, which was in fact proven by the debacle called Ares I. Replacing a single engine with three would be a massive engineering project. The entire lower section of the rocket would have to be rebuilt to handle higher stresses. The structure would have to be completely redesigned to create anchor points for the new engines. Also, was Vulcain ever tested in multi-engine configuration? Adjacent engines can significantly affect each other.


If you can't make Ariane 5 work for you the way it is (beside replacing the upper stage), why not focus on a different launcher?
 
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RGClark

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AdamF said:
The math aside, I am not sure whether I understand your arguments. You are proposing that a completely new launcher, built out of tested components, will be easier to man-rate than a tested launcher with proven track record.
What you are proposing is a completely new launcher, which was in fact proven by the debacle called Ares I. Replacing a single engine with three would be a massive engineering project. The entire lower section of the rocket would have to be rebuilt to handle higher stresses. The structure would have to be completely redesigned to create anchor points for the new engines. Also, was Vulcain ever tested in multi-engine configuration? Adjacent engines can significantly affect each other.
If you can't make Ariane 5 work for you the way it is (beside replacing the upper stage), why not focus on a different launcher?

If the the modifications to the Ariane 5 core stage were privately financed then there is little doubt it could be done at the few hundred million dollar range, or less, since the entire Falcon 9, which has a larger payload capability, was developed for that amount, even with newly developed engines and newly developed multi-stage structure. Note that the Falcon 9 has an even more complicated multi-engine architecture using 9 engines in the first stage.

Also, don't underestimate the cost of man-rating a multistage launcher with large strap-on boosters for such a large capsule as the Orion. Recall the debate about the Constellation program in regards to needing a new launcher in the Ares I for the Orion capsule. The question was wouldn't it be cheaper to man-rate the Delta IV Heavy and the largest version of the Atlas V with multiple strap-on boosters? NASA determined it would cost multi-billions of dollars to man-rate these vehicles for the heavy Orion capsule, just as what it would take for the full Ariane 5 to carry a manned Orion.

In contrast, for the smaller CST-100 capsule and Dream Chaser spaceplane, Lockheed has determined the smallest version of the Atlas V with no strap-on boosters would require minimal modifications to man-rate:

Human Rated Atlas V for Bigelow Space Station details emerge.
January 31st, 2007 by Braddock Gaskill
http://www.nasaspaceflight.com/2007/01/human-rated-atlas-v-for-bigelow-space-station-details-emerge/

Atlas V for Commercial Passenger Transportation.
Jeff A. Patton1 and Joshua B. Hopkins2
Lockheed Martin Space Systems Company, P.O. Box 179, Denver Colorado 80433
http://www.ulalaunch.com/site/docs/publications/AtlasVforCommercialPassengerTransportation20067268.pdf

I would have no objection though to European aerospace companies developing an entire new launcher capable of launching a smaller capsule, say, Dragon-sized or smaller, since as privately financed such a launcher could be developed in the few hundred million dollar range. Note also as shown by SpaceX, Boeing, and Sierra Nevada, the crewed capsules or spacecraft as privately financed can also be developed for amounts in that cost range.

BTW, I found another example that shows launchers as largely privately financed can cost only in the few hundred million dollar range. It's Orbital Sciences Taurus II, now called the Antares:

Is there profit in outer space?
"Getting a rocket into space is complicated business. In addition to expertise in physics, materials science, and electronics, you need the business savvy to create a sustainable company in an industry replete with flameouts."
Innovation.
December 2011
By Ted O'Callahan
http://qn.som.yale.edu/content/there-profit-outer-space

According to this article through the third quarter of 2011, Orbital spent under $350 million developing both the Antares launcher and the Cygnus unmanned cargo capsule. Since the Antares is expected to have its first test launch the first half of this year I gather that is most of the development cost.

In regards to a fully European crew capsule or spacecraft, European space enthusiasts have long lamented the demise of the Hermes spaceplane. The Hermes was of similar shape as Sierra Nevada's Dream Chaser, but about twice the linear dimensions. Then likely a half-sized Hermes would have comparable costs as the Dream Chaser as privately financed in the few hundred million dollar range.

Bob Clark
 
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RGClark

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Saw this quote of Arthur C. Clarke on sci.space.policy:
Every revolutionary idea seems to evoke three stages of reaction. They may be summed up by the phrases:

1- It's completely impossible.
2- It's possible, but it's not worth doing.
3- I said it was a good idea all along.

I feel SSTO's are at level 2 in Clarke's quote. Soon they will be at level 3.

Bob Clark
 
R

RGClark

Guest
A letter to the ESA:

====================================================

Hello. I was interested to read your report, "(titled deleted)" from
July 2011. On page 65 it states:

"The HHSC appears as the most promising launch concept:
– The current design clearly shows the advantages of a single High
Thrust Engine approach
yielding less costly propulsion systems."

Other reports I read also suggest producing a staged combustion
engine at about twice the thrust of the Vulcain. This would be a large
engine at about the thrust of the space shuttle main engines(SSME)
using also the complex and expensive staged combustion cycle of the
SSME. The SSME of course was quite an expensive development process
for the U.S. How convenient for EADS Astrium and the other Ariane 5
contractors that the recommended format for the NGL is the most
expensive one!

The idea that this would be a less expensive proposal than using just
two or three Vulcains on the Ariane 5 core stage is highly dubious. In
your report and in other reports I've seen this claim is simply stated
without given any comparison to the multi-engine Vulcain case. This in
itself is highly questionable. I have to wonder why the multi-Vulcain
approach among all those various other ones that are considered is not
even evaluated.

Your report stated the single engine concept has proven to be less
costly. Really? With ArianeSpace requiring a 100 million Euro subsidy
every year, without which it would go bankrupt?? Every other space
agency in the world, the U.S., Russia, China, India, has found it cost
effective to use multi-engine stages. It is highly dubious that the
ESA has discovered a great cost saving approach in always using a
single engine that no other space agency grasps, yet at the same time
ArianeSpace has to be propped up by megamillions every year because
this approach has not proven to be cost effective.

I've seen in other reports an attempt to compare this EADS Astrium
suggestion (I call it that because it appears that what's most
beneficial to EADS Astrium is what's most beneficial to the ESA) to
the Delta-IV model. That argument does not hold water either. The
Delta-IV could have been launched using two SSME's. However, the SSME
is a quite expensive engine meant to be reusable with high thrust
using the most expensive cycle in staged combustion. The U.S.
developed the RS-68 for the Delta-IV to get an expendable engine with
fewer parts and using the simpler and cheaper gas generator cycle, the
same cycle the Vulcain uses. It is also important to note in regards
to cost it is only 1 and 1/2 times the thrust of the SSME, not twice
the thrust, which also saved on cost.

But with the suggestion to develop a staged combustion engine at
twice the thrust of the Vulcain, the ESA is reversing this logic.
Because this engine will be using the most expensive combustion cycle
while having twice the thrust of the Vulcain it very likely will cost
more than two Vulcains, *plus* you have added on that very large
development cost for this large engine.

Another argument made for the large, high performance engine is that
it gives options in the size of the payloads launched. For instance,
the cores could be combined a la the Delta Heavy. However, the multi-
engine Ariane also has this capability. In fact, as a single stage it
could launch small payloads also, giving ArianeSpace another market
for launches. I have also done a preliminary calculation that two such
cores with the usual Ariane 5 upper stage could launch ca. 16 mT. And
with cross-feed fueling, which can increase payload about 25%, you
could get the 20 mT capability of the current Ariane 5.

An additional big problem with the large, expensive single engine
approach is that it is expected to come into use in the 2020 to 2025
time frame. The multi-Vulcain approach on the other hand probably
could be implemented within 2 to 3 years. I would have no objection to
the larger, higher performance engine being used at that later time
for a *larger* stage as long as for *now* the multi-Vulcain approach
is used.

It might be objected the ESA could not afford both. But SpaceX has
shown that as largely privately financed launchers can be developed
for markedly reduced costs than for government developed ones. It was
able to develop the nine engine, not just two or three, Falcon 9 for
ca. $300 million, and this included the costs of developing a whole
new engine and a whole new stage. It is larger in all of number of
engines, payload capacity, gross mass, dry mass, number of stages,
etc. than the multi-Vulcain Ariane core stage would be. Plus there is
also the key fact the engine and stage already exist for the multi-
Vulcain so you don't have that development cost.

Quite frankly if EADS Astrium couldn't figure out how to add on one
to two engines onto the Ariane 5 core *privately financed* for less
than the $300 million SpaceX spent to develop the *entire* Falcon 9,
then they are doing something wrong and should ask SpaceX to do it for
them. But there is no doubt in my mind that the European engineers are
at least as smart as the SpaceX engineers if not smarter and can do it
in a low cost fashion if they have to.

Yes, if they have to. EADS Astrium and the ESA are in a partnership.
The ESA needs EADS Astrium for their launchers and spacecraft, but
EADS Astrium needs the ESA for its aerospace division. Then one way
the ESA could encourage EADS Astrium to privately finance the
conversion of the Ariane core to multi-engines is to agree to pay for
the development of the larger, higher performance engine for that
later time frame.

Considering the size of the Ariane core stage compared to the entire
Falcon 9 rocket, I suspect this conversion could be done, privately
paid for, for under $100 million, really no problem at all for EADS
Astrium to finance it themselves. But there is a very important way
EADS Astrium could attract financing from outside investors. Reports
recently are that Europe has given up on plans of an indigenous manned
spaceflight capability because of cost. But SpaceX has shown and NASA
has confirmed with its commercial crew program that manned launchers
and spacecraft can be developed for costs in the few hundred million
dollars range as privately financed, perhaps with governmental seed
money.

Then a quite important advantage of the multi-Vulcain Ariane approach
is that both the single stage and two stage versions can be used for
manned launchers. So this would provide Europe with a manned
spaceflight capability at a short time frame and at low cost. This is
clearly something that could attract outside investors.

To summarize, the ESA should make a public accounting of the
comparison of the multi-Vulcain approach compared to the new large,
expensive engine approach for a new launcher. Evidence from other
space agencies suggests the multi-engine approach can be cost
effective. The ESA should encourage EADS Astrium to privately finance
the conversion. Lastly, and most importantly, the multi-engine
approach can provide Europe with a manned spaceflight capability in a
short time frame.


Robert Clark

...

====================================================
 
R

RGClark

Guest
I looked up references on the Japanese H-II rocket since I remembered it was hydrogen-fueled to see if it could be SSTO. I was surprised to see that JAXA in upgrading the H-IIA to the H-IIB, that they converted the single engine on the first stage to two-engines. Contrary to the ESA, they did this to save on costs rather than developing a whole new, larger engine:

Rocketing to the future.
http://www.gov-online.go.jp/pdf/hlj_ar/vol_0027e/05-07.pdf

Mitsubishi Heavy To Invest In Next-Generation Rocket.
by Staff Writers
Tokyo, Japan (AFX) Jun 14, 2006
http://www.spacedaily.com/reports/Mitsubishi_Heavy_To_Invest_In_Next_Generation_Rocket.html

The development cost for the conversion was 27 billion yen. But 5 billion yen of this was paid for by Mitsubishi Industries as prime contractor, as described in the second article. Note also that this 5 billion yen cost involved increasing the width of the tanks, which wouldn't be needed in the Ariane 5 case. It is known that increasing the width of the tanks involves a significant cost increase. Then we might estimate the cost as 22 billion yen, or $194 million by the exchange rate used in the second article without this tank width change. This is about what the ESA gave ArianeSpace last year as a subsidy.
Note also JAXA was using the opposite of the financing ratio suggested by the SpaceX success and NASA's commercial crew program success, with most of the cost being paid for by the government and only a fraction being paid for by private financing.
Following the SpaceX model of the majority of the cost being privately financed, we might expect the cost to be cut by a factor of 5 to 10, so to $20 to $40 million.



Bob Clark
 

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RGClark said:
Following the SpaceX model of the majority of the cost being privately financed, we might expect the cost to be cut by a factor of 5 to 10, so to $20 to $40 million.

Wrong, the spacex model can not be used to judge every aerospace development. There were unique circumstances surrounding Spacex and Falcon.
 
R

RGClark

Guest
A letter to the Japanese Space Agency, JAXA:


-----------------------------------------------------------------------------------------------------------------
Hello. I saw your IAF reports on the H-II and proposed H-III launchers. I
thought you might be interested in the letter to the ESA copied below. The key
question is one of cost. I looked up references on the H-II rocket since I
remembered it was hydrogen-fueled to see if it could be SSTO. I was surprised
to see that JAXA in upgrading the H-IIA to the H-IIB, that they converted the
single engine on the first stage to two-engines. Contrary to the ESA, they did
this to save on costs rather than developing a whole new, larger engine:

Rocketing to the future.
http://www.gov-online.go.jp/pdf/hlj_ar/vol_0027e/05-07.pdf

Mitsubishi Heavy To Invest In Next-Generation Rocket.
by Staff Writers
Tokyo, Japan (AFX) Jun 14, 2006
http://www.spacedaily.com/reports/Mitsubishi_Heavy_To_Invest_In_Next_Generation_Rocket.html

The development cost for the conversion was 27 billion yen. But 5 billion yen
of this was paid for by Mitsubishi Heavy Industries as prime contractor as
described in the second article. Note also that this 5 billion yen cost
involved increasing the width of the tanks, which wouldn't be needed in the
Ariane 5 case. It is known that increasing the width of the tanks involves a
significant cost increase. Then we might estimate the cost as 22 billion yen,
or $194 million by the exchange rate used in the second article without this
tank width change. This is about what the ESA gave ArianeSpace last year as a
subsidy.
Note also JAXA was using the opposite of the financing ratio suggested by the
SpaceX success and NASA's commercial crew program success, with most of the
cost being paid for by the government and only a fraction being paid for by
private financing.
Following the SpaceX model of the majority of the cost being privately
financed, we might expect the cost to be cut by a factor of 5 to 10, so to
only $20 to $40 million for the conversion in the Ariane 5 case.

I was interested to see in one of your IAF reports you discussed the
possibility of manned launchers. I see also that you intend to make the H-III
be all liquid fueled. Solid-rocket boosters are problematical for manned
launchers because they can not be shut down. Perhaps you intend to use the
H-III for the purpose in that future time frame when it comes into use.
However, the H-IIB core stage can be a SSTO manned launcher in the current
time frame with small modifications. First the H-II core is not as well weight
optimized as the Ariane 5 core. You can improve that by using common bulkhead
design as used by the Ariane. Note this is a well understood lightweighting
method at this point, having been used back in the 1960's on the Apollo
cryogenic upper stages. Also, SpaceX has used it very effectively to give the
Falcon 9 first stage a 20 to 1 mass ratio.
You could also use aluminum-lithium alloy for the H-IIB core. This would cut
an additional 25% off the dry mass of the structure aside from the engines.
This would then give your stage an advantage over the Ariane 5 core since it
also does not currently use aluminum-lithium.
These structural changes are relatively low cost when you already have the
tooling in place for a certain diameter tank. You still though would have to
decrease the propellant load to lift off with only the two engines on the
stage without the side boosters. You can just fill the tanks partially to say
158 mT load, as used for example on the original version of the Ariane 5 core.
It would not cost too much to also cut down the length of the tanks
specifically for the 158 mT load. Lengthening or shortening tank size is not
too expensive as long as you use the same tooling for the same tank diameter.
However, you might also choose to add a third engine onto the core instead of
reducing the propellant load. This probably can be done for comparably low
cost or even less than adding the second one since you don't have the extra
expense of re-tooling for wider tank size.
In short JAXA, can in a short time frame join the group of manned space
flight agencies and at relatively low cost. Also at being the first to
demonstrate a SSTO vehicle JAXA will have accomplished a technical feat in
importance perhaps to rival Robert Goddards first flights with liquid-fueled
rockets.
The ESA already has the lightweight stages and moderately high efficiency
engines to do it. All they need to do is make the politically controlled
decision to add on a second engine to the Ariane 5 core stage. JAXA has the
advantage though in having already added on the second engine, and having more
efficient engines.

The only question now is who will be first to make the quantum leap to SSTO
launchers.


Bob Clark


==========================================================================
Hello. I was interested to read your report, "(title deleted)"
from July 2011. On page 65 it states:

"The HHSC appears as the most promising launch concept:
– The current design clearly shows the advantages of a single High Thrust
Engine approach
yielding less costly propulsion systems."

Other reports I read also suggest producing a staged combustion engine at
about twice the thrust of the Vulcain. This would be a large engine at about
the thrust of the space shuttle main engines(SSME) using also the complex and
expensive staged combustion cycle of the SSME. The SSME of course was quite an
expensive development process for the U.S. How convenient for EADS Astrium and
the other Ariane 5 contractors that the recommended format for the NGL is the
most expensive one!
The idea that this would be a less expensive proposal than using just two or
three Vulcains on the Ariane 5 core stage is highly dubious. In your report
and in other reports I've seen this claim is simply stated without given any
comparison to the multi-engine Vulcain case. This in itself is highly
questionable. I have to wonder why the multi-Vulcain approach among all those
various other ones that are considered is not even evaluated.
Your report stated the single engine concept has proven to be less costly.
Really? With ArianeSpace requiring a 100 million Euro subsidy every year,
without which it would go bankrupt?? Every other space agency in the world,
the U.S., Russia, China, India, has found it cost effective to use
multi-engine stages. It is highly dubious that the ESA has discovered a great
cost saving approach in always using a single engine that no other space
agency grasps, yet at the same time ArianeSpace has to be propped up by
megamillions every year because this approach has not proven to be cost
effective.
I've seen in other reports an attempt to compare this EADS Astrium suggestion
(I call it that because it appears that what's most beneficial to EADS Astrium
is what's most beneficial to the ESA) to the Delta-IV model. That argument
does not hold water either. The Delta-IV could have been launched using two
SSME's. However, the SSME is a quite expensive engine meant to be reusable
with high thrust using the most expensive cycle in staged combustion. The U.S.
developed the RS-68 for the Delta-IV to get an expendable engine with fewer
parts and using the simpler and cheaper gas generator cycle, the same cycle
the Vulcain uses. It is also important to note in regards to cost it is only 1
and 1/2 times the thrust of the SSME, not twice the thrust, which also saved
on cost.
But with the suggestion to develop a staged combustion engine at twice the
thrust of the Vulcain, the ESA is reversing this logic. Because this engine
will be using the most expensive combustion cycle while having twice the
thrust of the Vulcain it very likely will cost more than two Vulcains, *plus*
you have added on that very large development cost for this large engine.
Another argument made for the large, high performance engine is that it gives
options in the size of the payloads launched. For instance, the cores could be
combined a la the Delta Heavy. However, the multi-engine Ariane also has this
capability. In fact, as a single stage it could launch small payloads also,
giving ArianeSpace another market for launches. I have also done a preliminary
calculation that two such cores with the usual Ariane 5 upper stage could
launch ca. 16 mT. And with cross-feed fueling, which can increase payload
about 25%, you could get the 20 mT capability of the current Ariane 5.
An additional big problem with the large, expensive single engine approach is
that it is expected to come into use in the 2020 to 2025 time frame. The
multi-Vulcain approach on the other hand probably could be implemented within
2 to 3 years. I would have no objection to the larger, higher performance
engine being used at that later time for a *larger* stage as long as for *now*
the multi-Vulcain approach is used.
It might be objected the ESA could not afford both. But SpaceX has shown that
as largely privately financed launchers can be developed for markedly reduced
costs than for government developed ones. It was able to develop the nine
engine, not just two or three, Falcon 9 for ca. $300 million, and this
included the costs of developing a whole new engine and a whole new stage. It
is larger in all of number of engines, payload capacity, gross mass, dry mass,
number of stages, etc. than the multi-Vulcain Ariane core stage would be. Plus
there is also the key fact the engine and stage already exist for the
multi-Vulcain so you don't have that development cost.
Quite frankly if EADS Astrium couldn't figure out how to add on one to two
engines onto the Ariane 5 core *privately financed* for less than the $300
million SpaceX spent to develop the *entire* Falcon 9, then they are doing
something wrong and should ask SpaceX to do it for them. But there is no doubt
in my mind that the European engineers are at least as smart as the SpaceX
engineers if not smarter and can do it in a low cost fashion if they have to.
Yes, if they have to. EADS Astrium and the ESA are in a partnership. The ESA
needs EADS Astrium for their launchers and spacecraft, but EADS Astrium needs
the ESA for its aerospace division. Then one way the ESA could encourage EADS
Astrium to privately finance the conversion of the Ariane core to
multi-engines is to agree to pay for the development of the larger, higher
performance engine for that later time frame.
Considering the size of the Ariane core stage compared to the entire Falcon 9
rocket, I suspect this conversion could be done, privately paid for, for under
$100 million, really no problem at all for EADS Astrium to finance it
themselves. But there is a very important way EADS Astrium could attract
financing from outside investors. Reports recently are that Europe has given
up on plans of an indigenous manned spaceflight capability because of cost.
But SpaceX has shown and NASA has confirmed with its commercial crew program
that manned launchers and spacecraft can be developed for costs in the few
hundred million dollars range as privately financed, perhaps with governmental
seed money.
Then a quite important advantage of the multi-Vulcain Ariane approach is that
both the single stage and two stage versions can be used for manned launchers.
So this would provide Europe with a manned spaceflight capability at a short
time frame and at low cost. This is clearly something that could attract
outside investors.

To summarize, the ESA should make a public accounting of the comparison of
the multi-Vulcain approach compared to the new large, expensive engine
approach for a new launcher. Evidence from other space agencies suggests the
multi-engine approach can be cost effective. The ESA should encourage EADS
Astrium to privately finance the conversion. Lastly, and most importantly, the
multi-engine approach can provide Europe with a manned spaceflight capability
in a short time frame.



Robert Clark


c.f.,

A low cost, all European, manned launcher.
« on: March 09, 2012, 07:14:49 pm »
http://www.secretprojects.co.uk/forum/index.php/topic,14692.msg146544.html#msg146544

Re: A low cost, all European, manned launcher.
« Reply #21 on: March 22, 2012, 04:27:58 pm »
http://www.secretprojects.co.uk/forum/index.php/topic,14692.msg147801.html#msg147801
=====================================================================================
 

Byeman

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That is very delusional for someone with only an internet education in aerospace engineering to send such a letter, especially when they don't have all the facts nor insight into the organization's desires. The most glaring issue is that there are items that are blatantly wrong in the letter.

This letter is going directly into the trash can.
 

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Hey! I have an Internet Ph.D. in aerospace engineering! Watch it now! :p

OK, all joking aside now. Clark, where do you get off on the illusion that you will single-handedly influence the policies of JAXA and ESA toward SSTO with one letter? Good luck with that.

They're actual space agencies, you're not. And more likely than not, some engineer within both organizations has already hit on the same ideas you have. You're not breaking new ground here.

So please kindly stop grandstanding on our forum like you're some kind of messiah for SSTO.
 

Byeman

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Not to mention that this forum about real "Secret Projects". Clark, having been booted off of other legitimate forums on spaceflight, is just looking for another vehicle to air his ideas in which real world constraints are absent.

Here is some of the nonsense that Clark has proposed in the past.

http://forum.nasaspaceflight.com/index.php?topic=11429.0
 
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RGClark

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XP67_Moonbat said:
Hey! I have an Internet Ph.D. in aerospace engineering! Watch it now! :p
OK, all joking aside now. Clark, where do you get off on the illusion that you will single-handedly influence the policies of JAXA and ESA toward SSTO with one letter? Good luck with that.
They're actual space agencies, you're not. And more likely than not, some engineer within both organizations has already hit on the same ideas you have. You're not breaking new ground here.
So please kindly stop grandstanding on our forum like you're some kind of messiah for SSTO.

The idea that SSTO's are unfeasible stems from analyses in 1950's and 1960's where engines had low efficiency and stages, by and large, were heavy weight. However, that hasn't been true since the 1970's. Since then, both the engines and stages have had the efficiency required for SSTO.
Unfortunately, many in the industry still view the idea of SSTO's from the standpoint of the state of the technology from 50 years ago. An analogy. Around the turn of the century many scientists said heavier than air flight was impossible. It's an interesting fact that they were actually right, with the technology at the time. The most common combustion engine at the time was steam engines, and they were too heavy for the job.
The internal combustion engine was coming into use then with the automobile. And they were still too heavy. Orville and Wilbur Wright had computed the required power to weight ratio for the internal combustion engine they needed and realized it didn't exist. They actually had to create it themselves. They used the lightweight metal aluminum just coming into common use at the time for the engine block. Previously it had been far too expensive.
(By the way the Wright brothers mother had a mathematics degree. It has been noted that the Wright brothers were far more systematic in their use of mathematics and in comparing their results with their formulas predictions than the other teams attempting heavier than air flight. I'm inclined to believe their more mathematical focus on the problem is something they learned from their mother.)
So in a very real sense it was advances in lightweight materials that made the airplane possible that previously was in fact technically impossible. A similar scenario exists in regards to SSTO's. Advances in lightweighting structures have made stages of sufficient lightweight for a feasible SSTO. Further material advances such as aluminum-lithium alloy, which can save 25% in weight off the usual aluminum alloys used, and composites which can save 40%, have made it so that SSTO's can carry actually quite high payload fractions, comparable even to multi-stage rockets now in common use.


Bob Clark
 
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RGClark

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Byeman said:
That is very delusional for someone with only an internet education in aerospace engineering to send such a letter, especially when they don't have all the facts nor insight into the organization's desires. The most glaring issue is that there are items that are blatantly wrong in the letter.
This letter is going directly into the trash can.

Sorry, but this topic is far too important to allow it to degenerate into an exchange of insults. Through SSTO's manned spaceflight can become low-cost and routine, and in a short time frame.
You can continue with the insults if you want. I'll stick to the science.

Bob Clark
 

overscan (PaulMM)

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Anyone who wants this topic reopened, send me a PM explaining why.


Anyone interested in Bob's ideas can check out his blog:


http://exoscientist.blogspot.com
 
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