Stratolaunch

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Sure, if that's what you feel you need to tell yourself (and try to tell others) to save face, by all means, go with that. You claimed to have *hard data*, but you couldn't (or wouldn't) even provide one concrete reference, and remember that objective information is the foundation that this forum is built on. So until you can quote a verifiable source rather than trying to turn absence of evidence into evidence of absence, I wholeheartedly concur with your "meh"...
 
Archibald said:
Goddam boiloff, forgot that one...

Boiloff losses could potentially be avoided by using subcooled propellants, see for example https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20180000059.pdf
 
martinbayer said:
Sure, if that's what you feel you need to tell yourself

So, you are either unwilling or unable to read what was actually written, and prefer to stick with your strawmen. The reasons for that willful blindness are yours, and are of no interest to me... just like any further "wisdom" you might try to excrete. Fortunately, this forum has an "ignore" feature. So... buh-bye now.
 
martinbayer said:
I never claimed they were the same, rather than qualitatively related, but I think at least the high altitude flights of the X-15 would in parts be somewhat analogous to an air launched orbiter zoom maneuver.

No, they aren't since the Stratolaunch rockets would not have wings.
 
martinbayer said:
Archibald said:
Goddam boiloff, forgot that one...

Boiloff losses could potentially be avoided by using subcooled propellants, see for example https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20180000059.pdf

Nonsense. One of the selling points of airlaunch was quick reaction time or multiple launch sites, which is not going to happening with a 12hr loading time or unless subcooling GSE is at all sites.
 
martinbayer said:
Because just a few years ago your very kind of reasoning was actively being used by some people against SpaceX, when precisely zero reusable Falcon 9 ballistic cores had been built and flown.

Not really. The issue is still there, it wasn't that stages couldn't be landed and reused. It is is it worth it? Most of SpaceX cost savings are from the vehicle design, operations and young labor pool. SpaceX vehicles were cheap before the first time a stage was reused.
 
Byeman said:
martinbayer said:
I never claimed they were the same, rather than qualitatively related, but I think at least the high altitude flights of the X-15 would in parts be somewhat analogous to an air launched orbiter zoom maneuver.

No, they aren't since the Stratolaunch rockets would not have wings.

While the expendable ballistic rockets intended to be the initial Roc payloads wouldn't, the reusable Black Ice orbital spaceplane, which is for example discussed at https://www.theverge.com/2018/8/20/17759930/stratolaunch-airplane-spaceplane-rockets-air-launch-pegasus, http://www.thedrive.com/the-war-zone/23031/meet-stratolaunchs-family-of-space-launch-vehicles-for-its-huge-roc-mothership, and https://www.geekwire.com/2018/stratolaunch-revives-vision-launching-space-plane-monster-airplane/, and was explicitly mentioned in this very thread before, most certainly would - are you perhaps just "winging" it in this thread?
 
Byeman said:
martinbayer said:
Archibald said:
Goddam boiloff, forgot that one...

Boiloff losses could potentially be avoided by using subcooled propellants, see for example https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20180000059.pdf

Nonsense. One of the selling points of airlaunch was quick reaction time or multiple launch sites, which is not going to happening with a 12hr loading time or unless subcooling GSE is at all sites.

While quick reaction *might* be of some interest to the DOD (depending on exactly which space architecture element currently really is the long pole in orbital payload launch), it really isn't a current consideration for most commercial and civil customers, which is in my understanding the market segment Stratolaunch was mainly targeting in the long run.
 
Byeman said:
martinbayer said:
Because just a few years ago your very kind of reasoning was actively being used by some people against SpaceX, when precisely zero reusable Falcon 9 ballistic cores had been built and flown.

Not really. The issue is still there, it wasn't that stages couldn't be landed and reused. It is is it worth it? Most of SpaceX cost savings are from the vehicle design, operations and young labor pool. SpaceX vehicles were cheap before the first time a stage was reused.

I see no reason why a winged spaceplane might not have benefited from advantages in terms of design, ops and comparatively cheap labor as well, if Paul Allen were still alive. I am still curious though about your on the record certainty that the Roc sizing was not driven by any previous reusable spaceplane studies, given the ultimate Black Ice goal, especially since you seem to have been oblivious to the existence of that concept...
 
"are you perhaps just "winging" it in this thread?"
Given that the Roc in particular, never mind carrier/orbiter composite aircraft in general, still has to fly at all, I think we are all heavily winging it here.

May I ask that we keep this thread civil?
 
steelpillow said:
"are you perhaps just "winging" it in this thread?"
Given that the Roc in particular, never mind carrier/orbiter composite aircraft in general, still has to fly at all, I think we are all heavily winging it here.

May I ask that we keep this thread civil?

Although the overarching topic of this thread is Stratolaunch in general, keeping in mind that the Mriya has successfully flown with an airlifted total payload of over 250 metric tons, and that this plane was envisioned as the carrier aircraft for the Interim Hotol concept that I have brought up before in this thread, to me the successful first flight of the Roc really isn't the critical pacing item in this particular line of discussion regarding a reusable subsonically air launched orbiter.
 
martinbayer said:
I see no reason why a winged spaceplane might not have benefited from advantages in terms of design, ops and comparatively cheap labor as well, if Paul Allen were still alive.

There are many reasons why. First major one is that Paul Allen had nothing to do with the design or engineering, so his presence is immaterial. Two, he is not Elon Musk. Three, the company is not vertically integrated. Do I need to go on.
 
martinbayer said:
it really isn't a current consideration for most commercial and civil customers, which is in my understanding the market segment Stratolaunch was mainly targeting in the long run.

Yes, it is. They also wouldn't like the longer prep time before launch.

And, there are other drawbacks. Example, Falcon 9 can only delay 15 or minutes once the sub cooled propellants are on board. Not really useful for vehicle built for loitering.
 
martinbayer said:
Archibald said:
Goddam boiloff, forgot that one...

Boiloff losses could potentially be avoided by using subcooled propellants, see for example https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20180000059.pdf

And no again. That is for an upperstage with super insulation.
 
Byeman said:
martinbayer said:
I see no reason why a winged spaceplane might not have benefited from advantages in terms of design, ops and comparatively cheap labor as well, if Paul Allen were still alive.

There are many reasons why. First major one is that Paul Allen had nothing to do with the design or engineering, so his presence is immaterial. Two, he is not Elon Musk. Three, the company is not vertically integrated. Do I need to go on.

Allen was quite obviously the founder of and driving force behind Stratolaunch and was willing to invest substantial amounts of funding into the project, which made his presence *highly* material for the continuation of the associated efforts, as is evident by the cancellation of launch vehicle related work not long after his death, since whoever is now in charge evidently does not share his vision.
 
Byeman said:
martinbayer said:
it really isn't a current consideration for most commercial and civil customers, which is in my understanding the market segment Stratolaunch was mainly targeting in the long run.

Yes, it is. They also wouldn't like the longer prep time before launch.

And, there are other drawbacks. Example, Falcon 9 can only delay 15 or minutes once the sub cooled propellants are on board. Not really useful for vehicle built for loitering.

Quote from https://spacenews.com/stratolaunch-charts-course-tough-market/:

"Commercial communications satellites are among the payloads Stratolaunch is gunning for.

“There is a thriving communications satellite market for small- to medium-class communications satellites,” Stratolaunch board member and former NASA Administrator Mike Griffin said at the company’s Dec. 13 press conference. “This would make a very effective launcher for such things.”

Griffin also said that Stratolaunch had its eye on a government market that produces “unmanned scientific satellites of one kind or another … at least half a dozen or so a year.” Most of these, he said, would be NASA payloads; a few would be military."

Quote from https://www.nbcnews.com/mach/science/billionaire-readies-world-s-largest-plane-launch-rockets-space-ncna909251:

"Eventually, Stratolaunch Systems plans to develop a “heavy” MLV variant using two half-length MLVs as side boosters. That rocket would handle payloads of up to 13,000 pounds.

Those capacities will place the rockets in an untapped region of the burgeoning commercial spaceflight market."

While the first quote mentions "a few" unmanned scientific satellites that would be military (and as scientific payloads would in all likelihood not require launch on demand), both sources agree on the emphasis on the commercial satellite market, at least in the near to medium term. Please provide *any* concrete sources (with verifiable online links) that contain any evidence of current commercial satellite launch customers requiring quick reaction and loiter capabilities for their payload deployments. Note also that while the references above pertain to expendable Stratolaunch vehicles, a reusable spaceplane would have the potential to address additional other and new market segments, including for example crewed orbital flights using a passenger module in the payload bay, that would also not realistically be expected to require quick reaction times or subsonic loiter.
 
Well I didn't wanted to create such a stir. Nor being pedantic in any way. I just wanted to assess what amount of payload could be send to the minimum-LEO by an expendable-LOX/LH2-rocket-stage-dropped-from-Roc. So 18 mt or a bit less.
The goal being to try and extrapolate a rocketplane out of this.

https://cdn.vox-cdn.com/thumbor/UdCl6W6n1EvTWLi77JRvrm_1apk=/0x0:1920x1080/1200x800/filters:focal(826x287:1132x593)/cdn.vox-cdn.com/uploads/chorus_image/image/60957099/Life_Cycle_2a__1_.0.jpg

Rocketplane mean (the way I see it, no idea if Black Ice was to be like this, I'm no Paul Allen)
a) no drop tank
b) no booster stage
c) in short, kind of Venture Star (not X-33)
d) dropped from Roc that is
e) no more than 250 mt

Build the rocketplane below out of the expendable rocket stage 18 mt of payload. If the wings +twin tail + undercarriage + payload weights more than 18 mt - GAME OVER. Zero payload, and no orbit.

http://aviationweek.com/site-files/aviationweek.com/files/gallery_images/Stratolaunch%20LV%20B_0.jpg
 
Byeman said:
martinbayer said:
Archibald said:
Goddam boiloff, forgot that one...

Boiloff losses could potentially be avoided by using subcooled propellants, see for example https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20180000059.pdf

And no again. That is for an upperstage with super insulation.

And it is also for a stage that is designed to store both cryogenic propellant components without any boiloff losses for *months*, rather than for just *hours* in case of a air launched orbital vehicle. This mission duration reduction by a factor of almost three orders of magnitude can reasonably be expected to more than compensate for any differences in insulation approaches and environmental conditions.
 
martinbayer said:
Byeman said:
martinbayer said:
Archibald said:
Goddam boiloff, forgot that one...

Boiloff losses could potentially be avoided by using subcooled propellants, see for example https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20180000059.pdf

And no again. That is for an upperstage with super insulation.

And it is also for a stage that is designed to store both cryogenic propellant components without any boiloff losses for *months*, rather than for just *hours* in case of a air launched orbital vehicle. This mission duration reduction by a factor of almost three orders of magnitude can reasonably be expected to more than compensate for any differences in insulation approaches and environmental conditions.

Still not applicable to an atmospheric much less an air launched vehicle. The insulation is for a vacuum.
 
martinbayer said:
any evidence of current commercial satellite launch customers requiring quick reaction and loiter capabilities for their payload deployments.

I never said that. The loiter time I was referring to is the time from GSE disconnect with the time to climb and getting to the launch box. That is on the order of an hour. Way outside of time of holding sub cooled propellants, especially LH2.
 
martinbayer said:
Griffin also said that Stratolaunch had its eye on a government market that produces “unmanned scientific satellites of one kind or another … at least half a dozen or so a year.” Most of these, he said, would be NASA payloads; a few would be military."

Quote from https://www.nbcnews.com/mach/science/billionaire-readies-world-s-largest-plane-launch-rockets-space-ncna909251:

"Eventually, Stratolaunch Systems plans to develop a “heavy” MLV variant using two half-length MLVs as side boosters. That rocket would handle payloads of up to 13,000 pounds.

Those capacities will place the rockets in an untapped region of the burgeoning commercial spaceflight market."

While the first quote mentions "a few" unmanned scientific satellites that would be military (and as scientific payloads would in all likelihood not require launch on demand), both sources agree on the emphasis on the commercial satellite market, at least in the near to medium term. Please provide *any* concrete sources (with verifiable online links) that contain any evidence of current commercial satellite launch customers requiring quick reaction and loiter capabilities for their payload deployments. Note also that while the references above pertain to expendable Stratolaunch vehicles, a reusable spaceplane would have the potential to address additional other and new market segments, including for example crewed orbital flights using a passenger module in the payload bay, that would also not realistically be expected to require quick reaction times or subsonic loiter.

Your "sources" are market pitches or fluff and not relevant.

Griffin does not speak for NASA. There would be little benefit to NASA to use this for scientific missions. The only reason NASA used Pegasus was for cost and not the air launch capability
 
Byeman said:
martinbayer said:
Byeman said:
martinbayer said:
Archibald said:
Goddam boiloff, forgot that one...

Boiloff losses could potentially be avoided by using subcooled propellants, see for example https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20180000059.pdf

And no again. That is for an upperstage with super insulation.

And it is also for a stage that is designed to store both cryogenic propellant components without any boiloff losses for *months*, rather than for just *hours* in case of a air launched orbital vehicle. This mission duration reduction by a factor of almost three orders of magnitude can reasonably be expected to more than compensate for any differences in insulation approaches and environmental conditions.

Still not applicable to an atmospheric much less an air launched vehicle. The insulation is for a vacuum.

The focus of my post was on the subcooled propellants - that's why I *specifically and explicitly* stated that the "mission duration reduction by a factor of almost three orders of magnitude can reasonably be expected to more than compensate for any *differences in insulation approaches and environmental conditions*" (emphasis mine). For atmospheric applications, *other* reusable cryogenic insulation concepts are applicable, for example as discussed in https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20050217094.pdf - why are you so dense (pun intended?).
 
Byeman said:
martinbayer said:
any evidence of current commercial satellite launch customers requiring quick reaction and loiter capabilities for their payload deployments.

I never said that. The loiter time I was referring to is the time from GSE disconnect with the time to climb and getting to the launch box. That is on the order of an hour. Way outside of time of holding sub cooled propellants, especially LH2.

First of all, that is definitely *not* loiter, which for example per Wikipedia is defined as "cruising for a certain amount of time *over a small region*" (my emphasis) - you apparently (?) really meant the transit flight time from takeoff point to launch point, which would obviously be kept as short as possible, both in terms of distance over ground as well as time, rather than flying around in circles. Once again, the potential cryogenic propellant holding time also depends on the chosen insulation concept, which the Falcon 9 that you tried to use as a counter example is utterly and completely *lacking*, see for example the discussion in https://elib.dlr.de/120200/1/SP2018_478_PA.pdf.
 
Byeman said:
martinbayer said:
Griffin also said that Stratolaunch had its eye on a government market that produces “unmanned scientific satellites of one kind or another … at least half a dozen or so a year.” Most of these, he said, would be NASA payloads; a few would be military."

Quote from https://www.nbcnews.com/mach/science/billionaire-readies-world-s-largest-plane-launch-rockets-space-ncna909251:

"Eventually, Stratolaunch Systems plans to develop a “heavy” MLV variant using two half-length MLVs as side boosters. That rocket would handle payloads of up to 13,000 pounds.

Those capacities will place the rockets in an untapped region of the burgeoning commercial spaceflight market."

While the first quote mentions "a few" unmanned scientific satellites that would be military (and as scientific payloads would in all likelihood not require launch on demand), both sources agree on the emphasis on the commercial satellite market, at least in the near to medium term. Please provide *any* concrete sources (with verifiable online links) that contain any evidence of current commercial satellite launch customers requiring quick reaction and loiter capabilities for their payload deployments. Note also that while the references above pertain to expendable Stratolaunch vehicles, a reusable spaceplane would have the potential to address additional other and new market segments, including for example crewed orbital flights using a passenger module in the payload bay, that would also not realistically be expected to require quick reaction times or subsonic loiter.

Your "sources" are market pitches or fluff and not relevant.

Griffin does not speak for NASA. There would be little benefit to NASA to use this for scientific missions. The only reason NASA used Pegasus was for cost and not the air launch capability

So you simply consider news reports that don't agree with your opinions as "market pitches or fluff and not relevant" - hmm, why does that remind me of online cries of "fake news"? By all means, if you have objectively documented sources that contradict the information provided under the links I proffered, please feel free completely to share them with us! Even if he does no longer officially speak for NASA, as a former NASA administrator who is now the Under Secretary of Defense for Research and Engineering, I consider Mike Griffin's views on the topic in question as *extremely* well informed. You also still have provided exactly zero evidence that backs up your claim that commercial satellite customers care about quick reaction launches, or that the Roc capability sizing was completely independent of the air launched orbiter studies I quoted previously.
 
Dear sirs, please avoid going personal and try to post for the general interest of the forum.
 
Awesome bird. Such a strange shape, so huge, it still looks unreal (or CGI) even in the pictures. Hope to see it in Le Bourget Airshow someday (since the An-225 made the trip in 1989, why not this one ?)
 

Today the #Stratolaunch aircraft flew for 2.5 hours over the Mojave Desert, reaching a top speed of 189 mph. Check out the historic flight here:

#StratoFirstFlight


What an incredible morning for the Stratolaunch team! Thank you to our partners at @ScaledC for their hard work.

Learn more about today’s #StratoFirstFlight here:
bit.ly/2VIv49d

Press release:

Stratolaunch Completes Historic First Flight of Aircraft
April 13, 2019 Press Release

World’s largest aircraft takes to the sky for its test flight over Mojave Desert

MOJAVE, CA – April 13, 2019 – Stratolaunch Systems Corporation, founded by Paul G. Allen, today successfully completed the first flight of the world’s largest all-composite aircraft, the Stratolaunch. With a dual fuselage design and wingspan greater than the length of an American football field, the Stratolaunch aircraft took flight at 0658 PDT from the Mojave Air & Space Port. Achieving a maximum speed of 189 miles per hour, the plane flew for 2.5 hours over the Mojave Desert at altitudes up to 17,000 feet. As part of the initial flight, the pilots evaluated aircraft performance and handling qualities before landing successfully back at the Mojave Air and Space Port.

“What a fantastic first flight,” said Jean Floyd, CEO of Stratolaunch. “Today’s flight furthers our mission to provide a flexible alternative to ground launched systems. We are incredibly proud of the Stratolaunch team, today’s flight crew, our partners at Northrup Grumman’s Scaled Composites and the Mojave Air and Space Port.”

The test team conducted standard aircraft testing exercises. Initial results from today’s test points include:

Performed a variety of flight control maneuvers to calibrate speed and test flight control systems, including roll doublets, yawing maneuvers, pushovers and pull-ups, and steady heading side slips.
Conducted simulated landing approach exercises at a max altitude of 15,000 feet mean sea level.
The Stratolaunch aircraft is a mobile launch platform that will enable airline-style access to space that is convenient, affordable and routine. The reinforced center wing can support multiple launch vehicles, weighing up to a total of 500,000 pounds.

“We all know Paul would have been proud to witness today’s historic achievement,” said Jody Allen, Chair of Vulcan Inc. and Trustee of the Paul G. Allen Trust. “The aircraft is a remarkable engineering achievement and we congratulate everyone involved.”

For more information, please visit www.stratolaunch.com/news-and-features for fact sheet, aerial images and video of first flight. Please also follow @Stratolaunch on Twitter for the latest updates.
 
A fitting time for the Forum to be re-configured.

Chris
 
Roc – the world’s largest plane – takes flight ahead of Stratolaunch rocket goals

The “Roc” – Stratolaunch Systems Corporation’s air-launch carrier plane – has conducted its first test flight over the Mojave Desert in California. The world’s largest plane has been years in development ahead of Saturday’s major milestone as it flew for 2.5 hours without issue. It will eventually carry up to three Pegasus rockets, the first two of which are now being assembled at Vandenberg Air Force Base.
 
One can't help but wonder, will it have the life of The Spruce Goose or the An-225?
 
Official company video release:

Stratolaunch First Flight

Stratolaunch
Published on Apr 13, 2019

In partnership with Scaled Composites, Stratolaunch successfully completed the first flight of the Stratolaunch aircraft. As part of this initial flight, the pilots evaluated aircraft performance and handling qualities.

 
Landing seems to have been something. Take a look at the rare shot in the video.
 
With a 385 ft wingspan, ground effect must be one hell of a PITA...
 
It is a shame that Paul Allen was not there to watch the first flight. :'(
 
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