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Comment by scrumper | Hacker News Reader

Great read, thank you.

A very lucky man, especially given that his crew mate bailed out before him, at higher altitude, going slower. The fact that between deciding to bail and pulling the handle took 4,000' is astonishing: 780mph is very, very fast.

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Really puts into perspective (or doesn't) something like Columbia breaking up at somewhere around 14,000mph.

It was also at about 200,000ft at the time. There's not much air up there. I'd bet that in terms of impact, 780MPH at 4,000ft is significantly worse.

That's an interesting thought - is 780mph at 4000ft worse or just different? It's clear that the lower your altitude, the more air there will be to "interact" with - however, even at an extremely high altitude (with virtually no air), at those speeds I would imagine that there is absolutely 0% chance of survival given all of the heat generated (among other things).

You are surely correct about the heating, what with how it was melting and burning through various hardware on the Shuttle at that point. Expose a human to that and they won't last long, even if the aerodynamic stresses are survivable.

I recently watched what appeared to be a USAF ejection seat training video. One of the most interesting things was that most ejection fatalities were attributable to pilots taking too long to make the decision to pull the handles. Essentially, people often thought they had more time to try to save the aircraft than they actually did. Another interesting thing was how surviving pilots described their thought process prior to ejecting. Very by-the-book rather than seat-of-the-pants.

https://youtu.be/bJDtRZ0K7Y0

but getting ejected out first also means withstanding the force for a longer duration, especially going through the middle troposphere at high speed...I am not sure if that would be easier in terms of survival...

But to increase the chance, in this kind of high speed ejection situation, why not make the escape pod or capsule a standard configuration, in place of an ejection seat...I just feel a well-designed pod or a capsule would provide an extra layer to buffer the extremely strong impact...

And capsule or pod has been deployed on some super-sonic aircraft such as Rockwell B-1 Lancer (still in service at this time)...That might be more expensive and would definitely require much more complicated design and extended experiments...But comparing to human life, all the other costs would seem to me much less important...

I saw this quote from wikipedia, https://en.wikipedia.org/wiki/Escape_crew_capsule

  Kelly Johnson, founder of Lockheed Skunk Works, and developer of
  the U-2 and SR-71 Blackbird family of spy planes, commented on
  escape crew capsules when discussing development of the
  YF-12A (Blackbird) ejection seat: ".... I have never been
  convinced that a capsule ejection is required for anything other
  than high velocity re-entry from outer space...."

But clearly, a shredded suit is nothing like a capsule...

In the SR-71, the pilots wear a pressurized suit that's a lot more solid than a normal flight suit.

Incidentally, someone survived ejecting (unknowingly!) from one: http://theaviationist.com/2015/03/17/sr-71-mid-air-disintegr...

Given that air density at 80,000 feet is ~1/40th of sea level[1], 'ejecting' at Mach 3 there sounds... A lot more survivable then ejecting at 10,000 feet above sea level, doing Mach 1.

[1] http://www.engineeringtoolbox.com/standard-atmosphere-d_604....

He had the presence of mind to realize his instruments were wrong just in the nick of time. Seconds more and he would've ridden the plane into terrain.

Great read indeed. Walking outside felt different today.

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