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Apparently the abort test is actually between the demo and crew flights, still. Not in May (per Chris G tweet).

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16 hours ago, Ultimate Steve said:

Aww, yeah! Birthday launch!

Although there was a SpaceX launch last year that was supposed to be on my birthday but was delayed a day...

 

Also Reddit's screaming that the in flight abort test is currently scheduled for sometime in May. That's, like, two months from now! EDIT: This is incorrect, sadly. It also looks like Boeing is going to fly crew before SpaceX.

What are Boeing flying crew in? 

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8 minutes ago, Jaff said:

What are Boeing flying crew in? 

CST-100.

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16 hours ago, Ultimate Steve said:

Also Reddit's screaming that the in flight abort test is currently scheduled for sometime in May. That's, like, two months from now! EDIT: This is incorrect, sadly. It also looks like Boeing is going to fly crew before SpaceX.

Well that sucketh mightily.

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I had no idea that they had developed this. 

 

Im assuming it’s going up on an atlas? 

I had visions of that shuttle looking thing for a minute (x37?)

Edited by Jaff
?

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The shuttle looking thing was Dreamchaser, it was the third competitor for the contract to ferry NASAs astronauts to the ISS, but lost to Dragon 2/Starliner.

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4 minutes ago, Jaff said:

I had no idea that they had developed this. 

Im assuming it’s going up on an atlas? 

I had visions of that shuttle looking thing for a minute (x37?)

Nah, the X-37B is an experimental autonomous orbital spaceplane; it is used as a testbed for NatSec experiments. Also, it launches in a fairing, and it has no place for crew. It's been launched by both SpaceX and ULA.

You may have been thinking of Sierra Nevada's Dream Chaser, which is a manned spaceplane. NASA didn't end up picking it for Commercial Crew, though.

Boeing's CST-100 Starliner is basically Orion Lite -- a smaller version of Orion with a lighter heat shield, less dV, and shorter-term ECLSS. It will launch on the Atlas V N22 (no fairing, 2 SRBs, dual-engine Centaur).

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Dream chaser is the one I was thinking of. Seats 7.

 

how was that going to be flown? I.e how was it supposed to get up there? 

Shame really as I liked the look of that. And propulsive dragon landings. 

 

in the end we get a new version of Apollo and a curvier cargo pod.

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3 minutes ago, Jaff said:

Dream chaser is the one I was thinking of. Seats 7.

how was that going to be flown? I.e how was it supposed to get up there? 

Shame really as I liked the look of that. And propulsive dragon landings. 

in the end we get a new version of Apollo and a curvier cargo pod.

Dream Chaser would have been able to launch on an Atlas V or a Falcon 9 or even an Ariane 5. It had integral launch abort motors which would have also been used for orbital maneuvering.

Propulsive dragon landings were canceled.

The CST-100 is very similar to the Apollo CM.

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See that’s cool. 

 

So is propulsive dragon landings (I know they’ve been canned) 

 

apollo (star chaser) - been there 

dragon 2 (dragon 1 with seats) - done that 

 

im being childish I know but space exploration should be at the forefront of tech, which is why we all love those returning boosters. I just hope I don’t get old quickly and miss out of more cool stuff. 

 

Id have thought the dream chaser with its ability to sit on top of multiple boosters would have been seen to be more favourable in a world of steep competition.

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4 hours ago, Jaff said:

dragon 2 (dragon 1 with seats) - done that

Don’t worry, if all goes well, Dragon 2 won’t see much use.

*cough* SSTO BFS *cough*

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3 minutes ago, sh1pman said:

Don’t worry, if all goes well, Dragon 2 won’t see much use.

*cough* SSTO BFS *cough*

I don't foresee BFS being used in SSTO format for Commercial Crew. Really, really unlikely. For a lot of reasons.

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Just now, sevenperforce said:

I don't foresee BFS being used in SSTO format for Commercial Crew. Really, really unlikely. For a lot of reasons.

Why not? It doesn’t need a booster to get sub-10t payload to orbit. It can have a small capsule with crew on top of it, with a LES

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6 minutes ago, sh1pman said:

Why not? It doesn’t need a booster to get sub-10t payload to orbit. It can have a small capsule with crew on top of it, with a LES

Not with enough reserves for landing.

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Just now, sevenperforce said:

Not with enough reserves for landing.

You sure about that? It doesn’t need much fuel for landing, 400 m/s of dv or so. I somehow thought it could fly as a SSTO with 10t payload and land.  

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9 minutes ago, sh1pman said:

You sure about that? It doesn’t need much fuel for landing, 400 m/s of dv or so. I somehow thought it could fly as a SSTO with 10t payload and land.  

Not by any math I've ever seen. 

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5 minutes ago, sevenperforce said:

Not by any math I've ever seen. 

Well, if so, they’ll have to bring a booster along as well. Still cheaper than launching F9.

Edited by sh1pman

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We've heard Musk say that BFS is an SSTO, but nothing about landing. Of course the cargo version would have a substantially lower dry mass.

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22 minutes ago, tater said:

We've heard Musk say that BFS is an SSTO, but nothing about landing. Of course the cargo version would have a substantially lower dry mass.

Right. The tanker variant has enough tankage capacity to just barely make orbit, but it wouldn't have enough prop for deorbit or landing. And it would have TWR issues on takeoff.

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An SSTO with no meaningful payload or way to get back, as I recall. Heck, the booster could probably be called the same. Maybe even a FH side booster. 

Theoretical SSTO boosters are nothing new, even the old Atlas could. It’s that “meaningful payload” bit that’s the rub. 

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7 minutes ago, CatastrophicFailure said:

An SSTO with no meaningful payload or way to get back, as I recall. Heck, the booster could probably be called the same. Maybe even a FH side booster. 

Theoretical SSTO boosters are nothing new, even the old Atlas could. It’s that “meaningful payload” bit that’s the rub. 

Yes, a FH side booster can SSTO with a couple of tonnes of payload. Easy. But no way it's coming back.

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Link is worth it just for the commentary. :D

But dang, that is impressive. :o I drive a 60-foot articulated transit bus on occasion, and I get to see Boeing transporting wing spars in a special rig nearly this long from time to time, but these guys appear to be moving the booster without any kind of steerable trailer! That’s just nuts! :confused:

 

 

 

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5 hours ago, tater said:

We've heard Musk say that BFS is an SSTO, but nothing about landing. Of course the cargo version would have a substantially lower dry mass.

If it combines fuel from the first and second stages it can reach orbit in SSTO

10000 = 3700 * ln (full/empty) = ~15:1 mass. That means fuel tanks and structural would need, combined to be less than 6% of the weight. That is of course if they can reach orbit with less than 10000 dV. Boosters for such a large rocket would be trivial.

If he choose hydrolox then 10000 = 4400 * ln(full/empty)  = 9.705/1. Of you attached like 6 F9 booster to the side you could get probably a good 500 or 600 dV out of methalox. The other option is to cheapo drop tanks. Again better have extra thrust to do that.

Im looking at the chemical data for a reaction which a fuel mixture of 3.8:1. I come up with a value of 9.1MJ/kg of fuel.

Therefore there is potentially a theoretical Ve maximum of 4163 m/s. Since they are saying their Raptor engine has a Ve 3680 m/s there is some room for improvement.

I wonder if a BFS went off course and hit a city, how much damage might it do.

If the BFS carried in 150,000 kg in the S2 and say 4 times that in the lower stage that would be 750,000 kg at launch.

That times 8.7E6 MJ/kg is 6.5 terra joules of energy about 1/10th the size of little boy. 

 

 

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