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Blue Origin Thread (merged)


Aethon

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Superdracos use a different propellant, would their addition not add too much weight? Not sure of their weight

This site: https://www.reddit.com/r/spacex/comments/4fnu2l/what_it_takes_to_make_falcon_9_upper_stage/

Says it is 4t? So you need just under 40kN of thrust (unless I am wrong)

 Draco has a vacuum thrust of 400N, but probably a lot less ASL, so you would need too many to be practical.

Superdracos have 71kN so you would only need two of them (for balanced thrust).

No idea what the cold gas thruster thrust is.

 

 

Edited by Skylon
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4 hours ago, Skylon said:

Does anyone know if Elon plans to reuse the second stage of the F9 Block 5? 

I cant find many details on it.

No, there is currently no plan to reuse the Block 5 Falcon 9 second stage.

Honestly, the likelihood of second-stage reuse seems rather low even with the Falcon Heavy inaugural launch. It's hard to conceive a reuse system which would not require a complete second-stage redesign. But a second-stage redesign would mean Falcon Heavy's qualification flight would be useless for anything other than that redesigned reusable stage.

The only thing I could think of would be that they bolt some limited recovery hardware on top of the existing payload adapter. I suppose that in that case, they'd be able to use it for Block 5 as well, though net payload would be miniscule.

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The only recent talk has been attempting reuse of S2 on the FH demo flight. They're not sending anything that matters on the flight, and there will be plenty of excess mass available to attempt something with it.

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10 minutes ago, tater said:

The only recent talk has been attempting reuse of S2 on the FH demo flight. They're not sending anything that matters on the flight, and there will be plenty of excess mass available to attempt something with it.

I actually wonder how and what they do in this situation. I've designed a 3x (falcon heavy) first stage, and a 3 stage version of Space X re-usable rockets in KSP. Then found some payloads just too small for them, and landing the second stage with a lot of spare fuel is a bad idea.

 

However, IRL, do you just put less fuel in? You cannot use a smaller launch vehicle than the 2 stage... so what do you do when that is too "big/powerful"? I know you can double (and more) up busses. Would Space X look for a smaller craft, or SSTO (or SSTAlmostO) first stage?

Edited by Technical Ben
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They could add a heat shield (they've likely thought of anything they will try for a while, it's not entirely extemporaneous), and might try a deorbit burn, then either an entry burn or a heat shield to demonstrate phase 1 of a recovery (vs actually trying an ocean soft-land or anything). Ie: get whatever data they can get to make any further attempts less in the dark, data wise.

Edited by tater
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I wonder if Dream Chaser or old-style European Hermes shuttle wouldn't be a good idea for a reuseable second stage? Instead of standard stage put on top of a Falcon Heavy,use a winged\body lifting spaceplane that will deliver the payload to orbit Space Shuttle style. Then it will return to landing site via gliding, land on a runway and be towed to hangar for refurbishing. Something like a downscaled ITS. Falcon Heavy can lift what - 50+ tons to LEO? Plenty of power even for not-so-small shuttle.

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Perhaps putting parachutes on the engine and just returning that? Maybe Vulcan-style recovery? Still the problem of pressure but...

1 hour ago, Scotius said:

I wonder if Dream Chaser or old-style European Hermes shuttle wouldn't be a good idea for a reuseable second stage? Instead of standard stage put on top of a Falcon Heavy,use a winged\body lifting spaceplane that will deliver the payload to orbit Space Shuttle style. Then it will return to landing site via gliding, land on a runway and be towed to hangar for refurbishing. Something like a downscaled ITS. Falcon Heavy can lift what - 50+ tons to LEO? Plenty of power even for not-so-small shuttle.

Actually I think the shuttle weighs over 100 tons. But maybe without a second stage it could be lifted.

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2 hours ago, Scotius said:

I wonder if Dream Chaser or old-style European Hermes shuttle wouldn't be a good idea for a reuseable second stage? Instead of standard stage put on top of a Falcon Heavy,use a winged\body lifting spaceplane that will deliver the payload to orbit Space Shuttle style. Then it will return to landing site via gliding, land on a runway and be towed to hangar for refurbishing. Something like a downscaled ITS. Falcon Heavy can lift what - 50+ tons to LEO? Plenty of power even for not-so-small shuttle.

Winged recovery is a mixed bag. I know it's not something SpaceX is considering. Aerodynamics for the launch of a winged second stage is really tough; that's why the X-37 launches inside a fairing.

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Yeah, I'm pretty sure that having a winged second stage would require some first stage changes. At the very least, you'd need to mount some huge fins on the first stage for stability, like below, which would definitely affect landing.

220px-Dyna-Soar_on_Titan_booster.jpg

That's a DynaSoar on top of a Titan (note the huge fins at the bottom).

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6 minutes ago, TheEpicSquared said:

Yeah, I'm pretty sure that having a winged second stage would require some first stage changes. At the very least, you'd need to mount some huge fins on the first stage for stability, like below, which would definitely affect landing.

Then how does Dream Chaser fly without a fairing or wings on the Atlas V?

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1 minute ago, _Augustus_ said:

Then how does Dream Chaser fly without a fairing or wings on the Atlas V?

It's unclear weather dream chaser will fly in a fairing or not, the renderings for the cargo version (the one likely to fly) has folding wings to fit in a standard 5 meter fairing.

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4 hours ago, tater said:

The only recent talk has been attempting reuse of S2 on the FH demo flight. They're not sending anything that matters on the flight, and there will be plenty of excess mass available to attempt something with it.

They've also said they're using the silliest payload they can think of, AND trying to do everything on the cheap, being just a test flight...

...so my money's on a recovered Dragon, or part of one, bolted upside down on the top of the second stage. Just for the lulz. And the dataz. Even if when it's a complete failure, it's still a golden opportunity to get hard numbers on recovering the stage without compromising a paying payload or spending a lot.

 

On another note, did they ever announce why the next launch got delayed till the end of the month?

 

  

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16 hours ago, DarthVader said:

It's unclear weather dream chaser will fly in a fairing or not, the renderings for the cargo version (the one likely to fly) has folding wings to fit in a standard 5 meter fairing.

It's pretty clear that it flies inside a fairing.

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Meanwhile, in the non-SpaceX world, ULA has sent Cygnus otw to station in  their predictably perfect, boring way. Maybe we need a ULA thread. They might be "boring," but that's cause they get the job done, almost every time. Was fun to watch Centaur lifting the perigee post-apogee, then circularizing with RCS before the deorbit burn. 

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9 minutes ago, tater said:

Meanwhile, in the non-SpaceX world, ULA has sent Cygnus otw to station in  their predictably perfect, boring way. Maybe we need a ULA thread. They might be "boring," but that's cause they get the job done, almost every time. Was fun to watch Centaur lifting the perigee post-apogee, then circularizing with RCS before the deorbit burn. 

Nah, I'll stick with the "Innovations with a chance of explosions" channel. Come to see the future, stay for the floor show. :D

besides, this thread has the attention span of a sugared-up two-year-old...

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26 minutes ago, tater said:

Meanwhile, in the non-SpaceX world, ULA has sent Cygnus otw to station in  their predictably perfect, boring way. Maybe we need a ULA thread. They might be "boring," but that's cause they get the job done, almost every time. Was fun to watch Centaur lifting the perigee post-apogee, then circularizing with RCS before the deorbit burn. 

WHY DO YOU HATE SPACEX

Kidding, kidding.

The 360-degree video wasn't nearly as cool as I was anticipating, mostly because the launch itself was like...3 frames.

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27 minutes ago, CatastrophicFailure said:

Nah, I'll stick with the "Innovations with a chance of explosions" channel. Come to see the future, stay for the floor show. :D

besides, this thread has the attention span of a sugared-up two-year-old...

Heck, my sugared-up two-year-old can stick with one subject longer than this thread can.

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