What happens when you eject at 780mph (2010) | Hacker News Reader

What happens when you eject at 780mph (2010)

f-15e.info

157 pointsarnold_palmur39 comments

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.

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.

Great read indeed. Walking outside felt different today.

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....

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

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.

This probably helps to explain why aircraft design has flirted with full escape capsules https://en.wikipedia.org/wiki/Escape_crew_capsule in the past.

Yes, I was thinking about the same thing...

And I feel even a commercial airline could make a similar device a standard configuration...that might make flying more expensive, but perhaps we could be able to reduce the cost somehow when manufacturing in massive scale...

Ejector pods a standard part in airlines? My mind boggles at the amount of weight that would be added. Manufacturing scale might bring down the capital cost, but it would never bring down the operational cost of lugging around all that extra weight, not to mention the inspections and tests required to ensure the devices are working as expected. Airline tickets would be 2x the cost, if not more.

People were still willing to fly when the crude oil price was at $100+ a barrel, although I am not sure if a well-designed and tested escape capsule is more complicated than the plane it self...

I just feel that is do-able, and had we made a good one now, we could use it for all the years to come -- and that could also be used in other travels or in case of catastrophic event...

Surviving a water landing from an ejector seat takes a fair bit of training. IMO, a backup parachute system would probably be about as safe and cheaper. https://en.wikipedia.org/wiki/Ballistic_Recovery_Systems

Granted, scaling up from a https://en.wikipedia.org/wiki/Diamond_D-Jet to a 787 would be extremely difficult.

Mid-air accidents are a tiny fraction of plane crashes.

Not to mention the protocol for usage of something like that. Do people get to pull the handle whenever they feel like it?

This is interesting, if the plane could have 3 sections each with a parachute then if a bomb went off it might only take out 1 of the sections leaving whoever is in the other sections to survive.

> And I feel even a commercial airline could make a similar device a standard configuration

What failure are you trying to shield against? I can think of very very few commercial crashes where an escape pod would have helped.

Any capital invested in escape pods would be much better utilized trying to reduce the (already tremendously low) failure rate of aircrafts. I'm not convinced this OP isn't trolling...

Airliners are already the safest mode of travel out there. You are probably safer in your microscopic Economy-class seat at 36,000ft than you are lying in bed at home. The effort is probably more usefully spent elsewhere.

The B-58 Hustler escape capsule is probably the best operational example of this. It allowed pilots to eject at speeds up to Mach 2 (!!).

https://www.youtube.com/watch?v=QbgeUNjsenA

and this guy survived SR-7 mid-air disintegration at mach 3+, wearing pressure suit...

theaviationist.com/2015/03/17/sr-71-mid-air-disintegration/

I'd say the F-111's system is just about perfect, although having a chunk of the airplane (the cockpit) thrust away and deploy its own parachute isn't always going to be practical.

https://www.youtube.com/watch?v=M8l79lSjVMg http://www.f-111.net/ejection.htm

Very touching. He lost his friend during the ordeal.

https://youtu.be/HecyxhXDepU

Another great ejection story is http://www.damninteresting.com/rider-on-the-storm/

My fighter pilot fried has told me stories, he's said, "Ejecting is the last thing you want to do, you'll come out of it a few inches shorter, if you survived the 10% chance of dying from your neck hitting the canopy."

To combat against that risk of hitting the canopy, most modern fighter aircraft do a couple of neat things.

First, there is a linear shape charge embedded in the canopy. This is detonated at the moment ejection is initiated. This charge completely shatters the material. So instead of having a whole canopy flying about, the canopy is retained and the pilot ejects through this shattered material. The charge is supposed to shatter this such that the pieces are very small.

Ejection seats also have a couple of small posts at the top. The purpose of these is to assist in punching through the shattered cockpit.

Ejection is still the last resort, and your friend accurately relates the risks. But work is being done to make the process a little less risky.

Yeah, at the time I think they were flying training jets from the 80's haha. I'm not sure of the numbers but the number of fighter pilots who die in training is a real number...

Although, my friend also knows that his piloting days from inside the aircraft are numbered. Manned fighter jets/bombers, etc. will be a thing of the past.

This guy has certainly earned the definition of "badass". Holy crap.

Alexander Konovalov, survived an ejection at Mach 2.6 from Mig 25 http://www.flightgear.dk/mach26eject.htm

The dynamic pressure of going Mach 2.6 at 61,000 feet is equivalent to 450 knots at sea level—quite a bit less violent than what Udell endured, shockwaves and temperature extremes notwithstanding.

I wonder if he would have made it if he'd tried to pull out of the dive rather than ejecting. I was trying to figure the numbers - I get he'd have to achieve about 3g vertical deacceleration which I guess he could have got pulling the stick back for say 10g?

That's how a lot of pilots die in crashes. They think they can pull a plane out of a hopeless dive in time to save it, and they end up cratering. It was pitch black, he had no idea of the attitude of the plane, he was picking up speed, and he was at the absolute minimum safe distance to eject. At that point, it takes a cooler head to punch out than to try to save the plane.

Yeah, based on pilot interviews I've watched where they discuss the ejection decision process, this situation was a pretty clear-cut case of "definitely eject immediately". What really impressed me was how quickly he was able to realize there was a mismatch between the HUD data and the ambient sound in the cockpit, consult a second set of instruments, realize what was going on, and make the decision.

Holy shit

Indeed. That was a great read, and I said "Wow" out loud when I saw that he flew again after 10 months.

tl;dr - everything that can break will probably break. Everything else will just get torn to shreds.

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