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Blue Origin Thread (merged)


Aethon

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A Falcon Heavy could get the Orion into LEO, but then what? That's not what Orion is designed for. And the EFT-1 test is scheduled for december. They can't wait for 2017 for a FH to be ready.

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Read what I was responding to-he was complaining about the Orion test flight on a a Delta IV heavy, which is sat on the pad as I'm writing this. Even leaving that aside, FH as planned won't have remotely SLS' capability for BLEO trajectories; LEO might be good for bragging rights, but it's not a current government objective or large commercial market.

If by he you mean me, I was not complaining about the Delta ( although I could ). The SLS is what's up my behind, but as I said, I'm trying to grin and bear this. There's no point in arguing about the merits of something like spilled milk.

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Even leaving that aside, FH as planned won't have remotely SLS' capability for BLEO trajectories; LEO might be good for bragging rights, but it's not a current government objective or large commercial market.
A Falcon Heavy could get the Orion into LEO, but then what? That's not what Orion is designed for.

True, as is.

But if they'd been developing Orion for FH - rather than following the SLS path - they could have given FH a third stage/kick motor, or Orion lots more fuel.

SpaceX claims 53 metric tons to LEO for Falcon Heavy. According to the Wikipedia article, Orion is 21,250 kg total mass with 7,907 kg Service Module propellant (those numbers aren't cited though); if that's correct, that would leave over 30 metric tons for more fuel/a third stage/kick motor/whatever. And developing a 3rd stage/bigger service module/etc would probably be a lot cheaper than developing the whole SLS.

(And even 2 Falcon Heavy flights - say to take up a habitat and even more fuel - would be cheaper than 1 SLS flight.)

I just don't think that at this point, there's any percentage in developing a new LV that isn't either very reusable or some other innovation to be massively cheap.

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With only 53 tons to LEO you can't get Orion near the Moon, no matter what (chemical) stages you use. The mass ratios just don't add up.

The SLS is a pretty big improvement over the Shuttle IMO. Besides being able to launch much bigger payloads in one piece (so you could launch the entire ISS in 4-5 launches rather than 30+), it will be much cheaper than the Shuttle in terms of dollars per ton to orbit. It costs less to NASA per year (~$1.8 billion rather than ~$3 billion for the Shuttle). Plus it's actually on budget and ahead of schedule, partly due to its more efficient design compared to Shuttle and Ares. If the marginal cost estimates of $500 million per launch come true, it would even be competitive with the Falcon Heavy in terms of cost per mass in orbit. What we need now is for payloads to be developed.

In my opinion Orion is more of a waste of money. It's been in development since 2004 or so, and the total amount spent on it until its first crewed launch in will be greater than that spent on the SLS. It was originally designed for lunar missions, so it has some carryover baggage. A capsule designed specifically for longer-term missions like Mars would be more efficient. Orion can't really do much by itself, just go in orbit around the Moon and come back. Plus it's behind schedule right now.

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However, every single official NASA Mars design reference mission has an Orion capsule going to Mars along with a deep space hab, and then returning the crew to Earth. The reason for this is that direct entry at Earth's atmosphere is cheaper, Delta V-wise, than returning to low Earth orbit and waiting for a "space taxi."

Late to the party, I know, but:

Could the capsule seperate from the deep space hab to return to Earth while the hab slings around Moon to park for a while, maybe to be reused after bringing it into LEO with ion-drones or something?

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Late to the party, I know, but:

Could the capsule seperate from the deep space hab to return to Earth while the hab slings around Moon to park for a while, maybe to be reused after bringing it into LEO with ion-drones or something?

The hab could be reused, but would you really want to reuse it, after it's been lived in for 2 years? It will be full of trash, all supplies and consumables will be expended, and most of the equipment will be worn out or need refurbishing or repair.

To reuse it:

- You would first need to brake it into LEO or EML-1. This will need *a lot* of propellant, which you would have to bring all the way to Mars and back. The extra weight means that you need *much more* propellant to send this extra propellant on a mission. This means that the size of your spacecraft on departure increases significantly, maybe twice as big as if it was expendable.

- You would need to send up at least several maintenance missions, to replenish supplies and consumables, change filters and seals, repair stuff that's broken, clean everything up, and bring back 2 years of trash. It would likely be cheaper to just send up a new hab for the next mission.

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  • 2 weeks later...
Thats a mean joke, but i like it.

Just substitude the N-Word (the forum doesn't like) with German (as its been 70 years now, the new ones don't know anything about Tech) and it works fine ;)

yeah i know but i don't write XKCD although i just hope for the best for Orion and also for the Russian PPTK and the Dreamchaser once they resolve theirstuffright now

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SLS booster separation test.

http://www.nasa.gov/larc/space-launch-system-booster-separation-testing-brings-confidence-to-first-flight/index.html#.VElqd_nF-Yc

“Booster separation is a very critical phase of flight for the Space Launch System because the clearance between the core stage and the boosters is very small as they are pushed away,†said Langley engineer Jeremy Pinier. “It’s only about an inch full-scale so the boosters are almost grazing the core stage, but we can’t allow any contact whatsoever between the two in the real flight.â€Â

So it's not just me then.

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There is a point where the term "diminishing returns" begins to apply to recovering booster stages. I think that attempting to recover F9H core stages would be well beyond that. If SpaceX wants to reduce cost of the F9H by recovering engines from the core stage, I think they should look towards the past--specifically, the Atlas booster, and the S-ID first stage for evolved Saturn Vs proposed in the late 60s. Both used a "stage and a half" design where the outboard engines were mounted on a "collar" that could be jettisoned once they were no longer needed. While the Atlas's booster engines were expendable, the S-ID design was intended to not only increase payload, but to also reduce cost by having the four outboard engines recovered and refurbished for reuse on a future launch. The inboard engine on the S-ID would be a sustainer, and would not be recovered, but by recovering four out of five first-stage engines, the bulk of the stage cost could be recovered, compared to the S-IC.

The new F9 design, with the circular ring of outboard engines as opposed to the square nine-pack design used on the early boosters, would be ideal for a similar "stage-and-a-half" setup; it could even be configured as a dual-collar design, such that only four engines are jettisoned at a time, allowing even earlier reductions in thrust (and making recovery of all the engines simpler due to having less weight to land safely)...

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There is a point where the term "diminishing returns" begins to apply to recovering booster stages. I think that attempting to recover F9H core stages would be well beyond that. If SpaceX wants to reduce cost of the F9H by recovering engines from the core stage, I think they should look towards the past--specifically, the Atlas booster, and the S-ID first stage for evolved Saturn Vs proposed in the late 60s. Both used a "stage and a half" design where the outboard engines were mounted on a "collar" that could be jettisoned once they were no longer needed. While the Atlas's booster engines were expendable, the S-ID design was intended to not only increase payload, but to also reduce cost by having the four outboard engines recovered and refurbished for reuse on a future launch. The inboard engine on the S-ID would be a sustainer, and would not be recovered, but by recovering four out of five first-stage engines, the bulk of the stage cost could be recovered, compared to the S-IC.

The new F9 design, with the circular ring of outboard engines as opposed to the square nine-pack design used on the early boosters, would be ideal for a similar "stage-and-a-half" setup; it could even be configured as a dual-collar design, such that only four engines are jettisoned at a time, allowing even earlier reductions in thrust (and making recovery of all the engines simpler due to having less weight to land safely)...

I don't see SpaceX redesigning their flight hardware any time soon. While they might consider it if their current designs underperform, Elon has made it pretty clear their expectations of reusing the Falcon Heavy core and upper stage are low. I'll give them the benefit of the doubt and expect it will all come down to achieving a repeated series of successful, accurate landings on sea-platforms.

The primary goal of the sea-platform is to provide a method from which precision reentry and landing can be proven. The reuse of the Falcon Heavy core is just speculation on my part.

Edited by Airlock
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I have no idea how stable a barge at sea can be. It may be very possible they'll have some type of superstructure to insure it doesn't fall over once landing. Probably wouldn't be too hard to design something like this in KSP.

If SeaLaunch can do their thing from a converted oil platform, it must be possible. Maybe SpaceX could move to something more stable, like that. The barge could just be a proof of concept.

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There is a point where the term "diminishing returns" begins to apply to recovering booster stages. I think that attempting to recover F9H core stages would be well beyond that. If SpaceX wants to reduce cost of the F9H by recovering engines from the core stage, I think they should look towards the past--specifically, the Atlas booster, and the S-ID first stage for evolved Saturn Vs proposed in the late 60s. Both used a "stage and a half" design where the outboard engines were mounted on a "collar" that could be jettisoned once they were no longer needed. While the Atlas's booster engines were expendable, the S-ID design was intended to not only increase payload, but to also reduce cost by having the four outboard engines recovered and refurbished for reuse on a future launch. The inboard engine on the S-ID would be a sustainer, and would not be recovered, but by recovering four out of five first-stage engines, the bulk of the stage cost could be recovered, compared to the S-IC.

The new F9 design, with the circular ring of outboard engines as opposed to the square nine-pack design used on the early boosters, would be ideal for a similar "stage-and-a-half" setup; it could even be configured as a dual-collar design, such that only four engines are jettisoned at a time, allowing even earlier reductions in thrust (and making recovery of all the engines simpler due to having less weight to land safely)...

Problem with only returning the engines is that they would have to splashdown, adding control and fuel to do an accurate landing would be complicated, Another design where the engines was in a sort of miniature boosters who separated and landed might be possible but would be an totally different design.

Else I agree with you, one benefit is that the core and the boosters share most design so they might reconfigure aging boosters as core stages instead of doing major services.

An barge might be possible, not sure how stable it would be, thing it require some stabilization system it would also need an service ship.

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Maybe SpaceX could move to something more stable, like that. The barge could just be a proof of concept.

Spacex are only landing it on a barge temporarily while they have to. They just need to prove it works before being allowed to land on land.

Also despite how it looks I think the rocket is surprisingly stable. Most of the weight is low down with the engines and the rest is just empty fuel tanks.

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