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1 hour ago, sevenperforce said:

And if they brought their own air, and figured out a way to remotely unberth?

There is no way to unberth. The connections need to be closed from the active CBM. This is an exercice in futility. 

If the Soyuz are destroyed and vital ECLSS systems fail, there are redundant systems. If all redundant systems fail then no evacuation is possible.

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1 minute ago, Nibb31 said:

There is no way to unberth. The connections need to be closed from the active CBM. This is an exercice in futility. 

If the Soyuz are destroyed and vital ECLSS systems fail, there are redundant systems. If all redundant systems fail then no evacuation is possible.

But he's stipulating that "they [...] figured out a way to remotely unberth," so that objection can be taken as given. Unberthing and life support are a problem, the point is what other problems there might be.

3 hours ago, sevenperforce said:

would a docked Dragon 1 be enough to get the crew home safely?

That's a question about the re-entry and landing capabilities of the Dragon 1.

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3 minutes ago, Nibb31 said:

There is no way to unberth. The connections need to be closed from the active CBM. This is an exercice in futility. 

If the Soyuz are destroyed and vital ECLSS systems fail, there are redundant systems. If all redundant systems fail then no evacuation is possible.

Then let's take the what-if out of the equation, and just ask the question.

38 minutes ago, HebaruSan said:

But he's stipulating that "they [...] figured out a way to remotely unberth," so that objection can be taken as given. Unberthing and life support are a problem, the point is what other problems there might be.

That's a question about the re-entry and landing capabilities of the Dragon 1.

Exactly.

Does anyone know whether the re-entry profile, thermal management, chute deployment acceleration, and splashdown speed are reasonably safe for one or more passengers?

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3 minutes ago, Shpaget said:

Honestly, I'm not familiar with the acronym and google is failing me.

Entry Descent Landing :) 

Also, regarding the issue of CO2 scrubbing, I'm assuming opening the hatch and depressurising the cabin wouldn't be a viable solution? Of course, the astronauts would be tied to the wall or something, with their EVA suits on

Edited by TheEpicSquared
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Oh, I kept on searching EDL with oxygen, CO2 scrubber, life support and similar keywords. No wonder it didn't work.

Anyway, according to this, Soyuz takes about three and a half hours to deorbit from undocking, with almost two and a half hours being spent on gaining some distance from the ISS, conceivably for safety. In the scenario of all hell breaking loose, we can probably cut that down almost completely, (decouple, get a few hundred meter separation, assume attitude and burn retrograde) which leaves us with just one hour for the actual deorbit and landing.

If we assume similar timeline for Dragon, it might be survivable (as far as breathing goes). As for the descent profile and forces involved with deorbiting Dragon, I would guess it is within margins of survivability, after all, the general concept was designed with human rating in mind.

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19 minutes ago, sevenperforce said:

Then let's take the what-if out of the equation, and just ask the question.

Exactly.

Does anyone know whether the re-entry profile, thermal management, chute deployment acceleration, and splashdown speed are reasonably safe for one or more passengers?

Not for certain but SpaceX have returned quite a bit of cargo from the ISS and I haven't seen any 'OMG SpaceX trashed our delicate science experiments' articles in the media, so I'm guessing splashdown would be passenger-tolerable.

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19 minutes ago, sevenperforce said:

 

Does anyone know whether the re-entry profile, thermal management, chute deployment acceleration, and splashdown speed are reasonably safe for one or more passengers?

This. We know the Dragon can safely return 20 mice, and loft 40 (that's on the current cargo), so what's the limit? One human? A miniature horse? An unusually large lizard? A safari of pygmies from the African interior?

 

18 minutes ago, TheEpicSquared said:

Entry Descent Landing :) 

Also, regarding the issue of CO2 scrubbing, I'm assuming opening the hatch and depressurising the cabin wouldn't be a viable solution? Of course, the astronauts would be tied to the wall or something, with their EVA suits on

I don't think the hatch can be opened from the inside at all, especially when pressurized. Think Apollo 1.

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12 minutes ago, CatastrophicFailure said:

This. We know the Dragon can safely return 20 mice, and loft 40 (that's on the current cargo), so what's the limit? One human? A miniature horse? An unusually large lizard? A safari of pygmies from the African interior?

Not known because it hasn't been studied. There is no point in studying it because it simply isn't going to happen.

12 minutes ago, CatastrophicFailure said:

I don't think the hatch can be opened from the inside at all, especially when pressurized. Think Apollo 1.

And you're not going to get the entire crew to wear EVA suits because there aren't enough of them, they need to be donned in the airlocks with help from a third person, you'd have trouble getting from the airlocks to the Dragon wearing them, and there is no way you are going to manipulate the CBM controls while wearing one.

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21 minutes ago, Elthy said:

If i remember correctly Elon Musk himself stated that a reentry aboard a Dragon 1 is survivable (propably burried somewhere on Twitter).

we're talking about the dragon that's going up to the station, that dragon right?

if it wasn't then how would they reuse it?

oh your talking HUMAN rated, ooooh

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5 hours ago, Nibb31 said:

No. Beyond the fact that it can't unberth (you need someone inside to close the CBM and use the Canadarm), there certainly isn't enough CO2 scrubbing inside to hold 6 people for several hours.

Judging by the other replies, the EDL accelerations are okay. Surely CO2 scrubbers could be scavenged from somewhere, even an EVA suit. They could just stuff an empty or cut-down suit in if need be, that would at least slow down the CO2 buildup. As for unberthing, someone could sacrifice his/herself by remaining behind to unberth and save the rest. 

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50 minutes ago, StrandedonEarth said:

As for unberthing, someone could sacrifice his/herself by remaining behind to unberth and save the rest. 

This. In fact, if this were the movie it's increasingly sounding like, this would be the pivotal drama scene with lots of close ups of strained, sweaty faces, orders given and refused, and then the switcheroo right at the end with some emotional pounding on the window and two hands separated by a single pane of glass and a poignant one-liner, perhaps followed by a big "NOOOOO!"

Edited by CatastrophicFailure
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It's just F9. It's only ~5,000kg.

The F9 fairing is smaller on the outside, but slightly larger inside than Atlas (a few cm). I think being LV agnostic is a feature for X-37b, honestly.

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7 minutes ago, CatastrophicFailure said:

ULA must be ready to pop a space gasket about now. :D

Is the X-37 still in F9πr^2 territory, or will it need a FH?

That'll be a really cool launch to see, and because it'll be classified, we'll get that tracking camera all the way up again: D 

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36 minutes ago, CatastrophicFailure said:

ULA must be ready to pop a space gasket about now. :D

Time for them to step up, we all know they have it in them, they got fat and lazy though

Edited by Nothalogh
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