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If a pilot ejects, what is the autopilot programmed to do? (2018)

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Re: If a pilot ejects, what is the autopilot programmed to do? (2018)

#51

Earlier quoted context omitted.

Ejecting for for no reason would end the pilot's flying career. Ejecting for any reason will result in an investigation, at minimum. Pilots are expected to fly the airplane until the last extremity. So while yes it's possible, it's unlikely, and the return on investment of making the plane able to do something like "return to base" in that circumstance would be a large negative number.

Even ejecting with good reason is enough to end a fighter pilot’s career. The rates for significant back injury are between 1 in 3 and 1 in 2 depending on the design.

My understanding is they're automatically retired from flight after the second (or maybe third?) ejection, not automatically after the first.

Re: If a pilot ejects, what is the autopilot programmed to do? (2018)

#52
post #4

I think the most proper thing for the jet should be to destroy itself. In a war enviornment I would not like my enemy to gain intel about my military jets.

You could erase computer memory, but blowing up the plane won't stop them from gaining intel about the materials, mechanism, and whatnot that make up the plane. An explosion won't vaporize the airplane, just break it into smallish pieces. Those can be collected and analyzed to reconstruct most any detail about the construction of the airplane. They even do this with missiles and bombs. Even shell fragments. When artillery shells packed full of high explosives go off, their intricate fuse mechanisms are left remarkably intact.

Re: If a pilot ejects, what is the autopilot programmed to do? (2018)

#53
post #15
post #7

It seems like the sensible thing to do would be to fry / erase any IFF and encryption related stuff, but otherwise continue as before. E.g, if it's already been programmed to fly straight and level, continue to do that. If it's deactivated, stay deactivated. Just seems like a whole 'nother set of characteristics to test otherwise, as well as adding extra unpredictability. The aircraft is probably damaged / on fire, s…

If the autopilot is engaged, the pilot won't be ejecting, because the aircraft will be in some kind of controlled flight. Autopilots will be disengaging and lighting up a big red light in the cockpit well before the aircraft gets to the point where the pilot would consider ejecting. Remember that ejecting is an absolute last resort, since the pilot is quite likely to be injured and runs a significant risk of being ki…

Disagree--it can be entirely sane to eject from a fully functional aircraft.

1) Something is going catastrophically wrong with the plane. It's flying now, but soon that fire will burn through the hydraulics, safer to punch while it's still in controlled flight.

2) There is not enough fuel to put it on a runway. Once again, punch while it's still stable. We've even seen a civilian do that--ferry flight with one of those planes with an integrated parachute. He had a fancy rig with extra fuel in the cabin, it wouldn't feed. Without it he wasn't going to make Hawaii.

3) We have seen a Navy pilot correctly punch from a fully functional aircraft. He was on final when somebody launched an SM-2 at him. Low, slow, defenses off--no chance, he punched. He was pointed right at the carrier at the time, having an autopilot do something else would be a good idea. (There would always be a chance that the missile was destructed in time.)

And with semi-functional planes:

4) We have seen an Israeli pilot bring their bird back with one wing. He had to land very hot but there was a long enough runway, he was able to do it. But what if it's even worse? There can be enough damage that your minimum airspeed is above any runway you can reach or above what your wheels can handle. Or maybe the Navy would prefer the pilot to eject rather than risking a major mishap on the deck.

5) What if the problem is elsewhere? We have seen a pilot punch from an apparently-functional F-35. The problem was actually in his controls. (Yes, he has been found wrong--the first two investigations cleared him (if the plane is not responding properly to pilot inputs below 6,000' AGL, eject), they finally found a panel that would declare him wrong. Doesn't make him wrong.)

Re: If a pilot ejects, what is the autopilot programmed to do? (2018)

#54

A pilot would only eject if the aircraft was uncontrollable with no reasonable hope for recovery. Unlikely the autopilot can do anything deliberate at that point.

Unlikely, you say? That's why it's being discussed. Like, if a pilot ejected because the engines stop, but the control surfaces still work... Maybe the plane avoids a kindergarten on its dive to the earth-sky interface.

The plane doesn't know this. But this is part of why the ACES II seats are capable of zero-zero ejections. One of the scenarios in mind is allowing the pilot to steer for the open space without making it a suicide mission.

Re: If a pilot ejects, what is the autopilot programmed to do? (2018)

#55
post #15

Earlier quoted context omitted.

If the autopilot is engaged, the pilot won't be ejecting, because the aircraft will be in some kind of controlled flight. Autopilots will be disengaging and lighting up a big red light in the cockpit well before the aircraft gets to the point where the pilot would consider ejecting. Remember that ejecting is an absolute last resort, since the pilot is quite likely to be injured and runs a significant risk of being ki…

Disagree--it can be entirely sane to eject from a fully functional aircraft. 1) Something is going catastrophically wrong with the plane. It's flying now, but soon that fire will burn through the hydraulics, safer to punch while it's still in controlled flight. 2) There is not enough fuel to put it on a runway. Once again, punch while it's still stable. We've even seen a civilian do that--ferry flight with one of tho…

[deleted]

Re: If a pilot ejects, what is the autopilot programmed to do? (2018)

#56

Earlier quoted context omitted.

Even ejecting with good reason is enough to end a fighter pilot’s career. The rates for significant back injury are between 1 in 3 and 1 in 2 depending on the design.

My understanding is they're automatically retired from flight after the second (or maybe third?) ejection, not automatically after the first.

It feels like a good chunk of the comments here imply that ejection is a pretty common activity, hence the interest in what happens next, both to the pilot and the jet. I don’t have any ready statistics, but if ejection was a commonplace activity then the world‘s air forces would be depleted of planes in very short order. It wouldn’t shock me if there’s a policy about pilots who ejected more than x times, but I would be shocked if the policy was ever actually enforced, simply due to the rarity of it even being an issue.

Re: If a pilot ejects, what is the autopilot programmed to do? (2018)

#58
post #31

The analysis and conclusions of the responders here (2018) seem pretty invalidated by the 2024 F-35B ejection incident. Maybe more thought should be put into what the autopilot should do? https://www.marinecorpstimes.com/news/your-marine-corps/2024...

A single incident doesn’t invalidate anything. No one has argued that it’s impossible for a fighter to fly on for a significant period of time in good shape after a pilot ejects, or the pilot has never ejected mistakenly out of an air worthy aircraft. Rather the argument is that this is a vanishing rare occurrence and the complexities of trying to implement an unmanned auto pilot of a potentially damaged aircraft are probably not worth the handful of times it might be used. One incident doesn’t disprove that it’s vanishingly rare.

Re: If a pilot ejects, what is the autopilot programmed to do? (2018)

#59
post #39
post #35

I was astonished at the claim that pilots ejecting can lose half an inch of height due to spinal compression induced by the G-forces. Claims seem to be borne out: https://www.forcesnews.com/news/can-ejecting-aircraft-make-p... https://www.quora.com/Do-pilots-lose-height-when-they-eject-...

Making sure that the consequences are well-publicized also has the useful side-effect of making sure that ejection is regarded as a last resort.

You don't really get a rando who would be unaware of that in the pilot seat of a fighter jet very often.

Re: If a pilot ejects, what is the autopilot programmed to do? (2018)

#60
post #33

> The only victim of the accident was Wim Delaere, a computer science student reported to have been either 18 or 19 years old.[4][5][1] He was sleeping alone after celebrating the end of his university exams the previous day when the MiG crashed and killed him at 10:30 am. His mother and brother were shopping for groceries in Kortrijk, and his father was working in Ypres.[4] From the linked Wikipedia article on one o…

His death later inspired the movie Donnie Darko, about a kid in 1988 who is killed by a jet engine in similar circumstances.
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