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by ceejayoz 947 days ago
The real question here is what happens with a crewed second stage that has a problem with its engines/fuel. We’ve yet to see designs for the crewed interior beyond very conceptual stuff.

Maybe something like https://en.wikipedia.org/wiki/Escape_crew_capsule for launch abort.

3 comments

This same question was asked in the early years of commercial aviation. In the end, the industry (mostly) settled on aircraft designs that could passively glide reasonably well enough to land (sometimes). But some aircraft, e.g. military jets and Cirrus, came up with different answers (parachutes for the crew and for the whole aircraft, mostly).

We'll see how the commercial spacecraft industry deals with this, but I do think that we are at far too early of a stage to start expecting progress in this area. The first few decades of commercial spaceflight will be dangerous just like the first few decades of commercial aviation, or for that matter the first few centuries of commercial shipping. The answers, varied or uniform, will be interesting and I hope that I'll be around to see them.

Wonder if we'll ever have commercial aircrafts with whole aircraft parachutes.
No. Those systems can't really scale up in size and speed. And it would be pointless anyway because the few commercial airliner crashes that do occur are mostly during take off or landing where parachutes aren't very effective.
There's no parachuting from 900km/h
There's been a number of successful supersonic ejections of military pilots over the years. It's extremely dangerous and very likely to fail, but it's better than the alternative. The basic idea is a drogue chute stabilizes and slows the pilot.

Whether the same idea could be adapted to a whole plane I don't know, but I would be skeptical of just on the basis that you probably wouldn't trigger such a thing unless the plane has had a substantial failure such that it could overpower any drogue chute.

There is at least one documented survival at the insane speed of Mach 3: https://theaviationgeekclub.com/bailing-out-at-mach-3-the-in...
Here's Weaver's own account:

http://www.chuckyeager.org/news/sr-71-disintegrated-pilot-fr...

I love the serendipitous detail of what happened on his next flight, though I'm sure it was not so amusing when it happened.

Well, his _next_ flight was to see the body of Jim. But yes, the next Habu flight started off interesting.
i'd be willing to believe it's an economics thing more-so than a physics thing.

one could envisage a '747-like' sized plane with many passenger escape-pods similar to the pod from an B-58 Hustler -- but who would pay the astronomic cost for such a ticket?

and similar to what the other person in this thread mentioned : those escape pods won't help during takeoff/landing phases.

I believe that the crewed version is way in the future when operations are much better understood. There’s no chance in hell they’re catching that 2028 window to march.
How did Space Shuttle approach this problem?
As ceejayoz said, "Death". The system WillPostForFood mentioned is indeed, as he said, extremely limited.

In the very first missions with only two astronauts, the shuttle had ejection seats. They were removed when more than two people flew at a time, because a) it is not possible to add more, and b) crew ride on two decks, not one.

After the loss of Challenger serious consideration was given to designing some sort of escape capsule for the entire crew, but it was decided that the weight and practicality considerations were not worth it.

The bottom line is that it is impossible to design any practical means of high-speed travel that can cover all eventualities. A century of extensive experience has led to air travel being the safest way to travel on average, but there are still fatalities. Maybe once we have a century of experience with Starship and its descendants we'll be able to say the same about space travel.

There was a estimated 1/16 failure possibility for the first couple flights. Lots of edge-cases where: If XYZ happens, you die.

But we were in a hurry, so it was just part of the project.

They added this system after Challenger, seems extremely limited.

https://airandspace.si.edu/collection-objects/crew-escape-sy...

"The crew escape system was intended for emergency bailout use only when the orbiter was in controlled gliding flight and unable to reach a runway. "

I'd take my chances and stay with the orbiter

> The vehicle touches down at 214 to 226 miles per hour, back wheels first. The nose then touches down, the drag parachute is deployed, and the shuttle cruises to a stop.

That's a lot of energy to bleed off.

Death.