Ejection Seats | Hacker News Reader

Ejection Seats

steveblank.com

98 pointsalanthonyc22 comments

Fun practical joke, here's another.

http://steveblank.com/2009/05/13/gravity-will-be-turned-off/

I typed 30 copies, and using the master key I went into every squadron building bulletin board, and posted these orders from the base commander on all 30.

Sounds like a good way to find out how a stockade works.

I wonder how many technicians were killed by accident by the ejection seats versus how many pilots' lives were saved. If there are more accidents than ejection saves, I wonder if it's calculated such that pilots are more willing to take risks if they think they'll be helped out by the seats.

Also pilots might be worth more to the military ( cost of training + scarcity of a good pilot + experience )

I doubt that enters into consideration, actually. The military spends vast amounts of money trying to protect all servicemembers' lives, and knowing a couple veterans, veterans who have lost people in combat, I can tell you that the cost of training and such don't even enter into their minds. I doubt the culture is as cold about the subject as you suggest, even if it is otherwise good reasoning.

Pilots lives saved ~7,100 according to Martin-Baker the main U.S. seat manufacturer. Technicians killed ~20 My guess based on four years in the Air Force.

No pilot "wants" to eject. There is a high possibility of being injured, usually to the head, neck & back, even with the modern Martin-Baker & BF Goodrich ejections seats.

During a high-risk flight, the possibility of ejecting outside parameters is quite high, such as the recent F-22 crash where the pilot got killed during a high-speed ejection.

There have been pilots who eject once and ended their career due to injuries.

Right. Even if the physical damage isn't that bad, injuries such as a concussion can end your career. The military has pretty strict rules about this stuff.

Also relevant: how many pilots would not have gotten into the cockpit without the illusion of control given by an ejection seat?

The ejection seat creates the illusion that even if everything goes pear-shaped, you'll have a chance to survive. The real-life cost was often gruesome (see John McCain's stay in the Hanoi Hilton), but it gave pilots at least a chance.

If no pilots would get into the cockpit without ejector seats, they were worth it.

Based on the (admittedly small sample) naval and Marine aviators I've known, the ability to eject is not a factor.

These guys simply expect that they're better than everyone else in the air and can never be shot down. I think you pretty much need that attitude to be able to do the job.

   “Yeah on these seats the ejection sequence automatically starts when it grabs your legs. The rocket fires in 10 seconds.”

10 seconds to start the ejection? Ah, come on, that would just eject the dead body of the pilot from the plane wreck. You should have known better.

Actually a B-52 might normally fly in heights where even a 10-second straight vertical fall should not be a problem

Heights like...500 meters?

To my anonymous downmodder: the parent's text seemed to think it impressive that B-52s fly at a height where "even a 10-second straight vertical fall should not be a problem".

Basic physics shows that such a height is scarcely more than about 500m, the distance an object in freefall would fall in that time and whatever other distance would be traveled during deceleration.

What, exactly, is the justification for downmodding a comment pointing that out?

Planes don't (generally) freefall, a better assumption would be at least some amount of thrust involved. (not your downvoter however).

I don't think it's the fall that matters. The problem would come when the airplane begins to tumble. Rip the tail off a B-52, and I would expect it to rapidly tumble and subsequently disintegrate with unpleasant consequences for those inside. Furthermore, ejecting is probably more likely to succeed in straight and level flight than from a tumbling aircraft. For both reasons, it is desirable to eject quickly once it becomes necessary.

Additionally, a 10 second wait is unnecessary. We see from fighter ejector seats that ejection can be done in just a few seconds. What can possibly be gained by remaining once the seat is ready to eject?

http://www.boeing.com/defense-space/military/b52-strat/b52_5...

It's a story about a b52 that lost its vertical stabilizer. It flew to the nearest base and landed normally, six hours later at a different base because of wind problems at the first base.

10 seconds is plenty of time in a b-52. Obviously a fighter it is ludicrous :-) but a bomber is very different.

It seems odd that there's no way to remove the rockets. You wouldn't do maintenance on a loaded gun.

You certainly can remove the rockets, it just takes a lot of time and effort so isn't done for routine maintenance. Also, removing the rockets would probably be at least as dangerous as working with them there.

That's a shame. Nuclear weapons can be quickly/safely loaded and removed but the ejection seat rockets can't...

Ejection rockets seats don't need to be removed frequently. Nuclear weapons need to drop the instant someone hits the trigger. So why would you complicate the design of an ejection seat that needs to work under a wide variety of conditions?

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