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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)

#21

Post by throwup238 »

SoftTalker wrote: post #19
quotemstr wrote: post #14

Earlier quoted context omitted.

Huh? If I'm the human pilot, I can pull the ejection lever for multiple reasons, including my just being an idiot. The plane, after I eject, should do something reasonable. Maybe it * starts broadcasting a mayday? * crashes into the nearest large body of water? * attempts to fly itself back to base (we have the technology)? I mean, it has to do something and flying straight and level until it runs out of fuel is unli…

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.

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

#22

Post by RobotToaster »

SoftTalker wrote: post #9

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.

Planes that keep flying after an ejection do happen

https://en.wikipedia.org/wiki/Cornfield_Bomber

https://www.marinecorpstimes.com/news/your-marine-corps/2024...

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

#23

Post by cluckindan »

pdonis wrote: post #15
hex4def6 wrote: 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…

About one in 20 ejections results in death, usually due to low altitude, or being hit/crushed by the seat.

Compare to 20 in 20 jet airplane crashes resulting in death and suddenly pulling that lever might seem a worthwhile risk to take

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

#24

Post by jvanderbot »

quotemstr wrote: post #14
appreciatorBus wrote: post #11

Earlier quoted context omitted.

If this was possible it would just be part of regular flight control laws and would be used to avoid becoming uncontrollable in the first place.

Huh? If I'm the human pilot, I can pull the ejection lever for multiple reasons, including my just being an idiot. The plane, after I eject, should do something reasonable. Maybe it * starts broadcasting a mayday? * crashes into the nearest large body of water? * attempts to fly itself back to base (we have the technology)? I mean, it has to do something and flying straight and level until it runs out of fuel is unli…

I'll do my best. So you want to dedicate probably the rest of your career to automated diagnosis and recovery from crash conditions after ejection? Just so we can say we did a reasonable thing? Oh just the one case where the pilot rejects during level controlled flight you're saying we should be careful to let it continue on same course and speed? And if it's slightly changing course speed or altitude? Did we want to level out or continue the climb and turn? Do we attempt to maintain rate of climb even if it means throttling up? Descent?

The whole thing is so wildly ambiguous and niche that it's a black hole. When a pilot ejects the controller is gone. The controls are slack and it's just physics until fire.

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

#25

Post by whycome »

SoftTalker wrote: post #9

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.

This is silly. And not true. There is no “would” other than your own prediction. What if the pilot deliberately wanted to crash the plane but not do it intentionally?

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

#26

Post by estimator7292 »

yjftsjthsd-h wrote: post #6
darkhorn wrote: 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.

Not my wheelhouse, but doesn't that involve packing the aircraft with explosives, and wouldn't that involve risk of blowing up if someone else shoots you? Or is there some better way to self-destruct?

One could calculate the amount of energy in a given amount of explosive and smashing into the ground at high velocity. I'm too lazy to do so, but I can tell you they're on the same scale.

A heavy object moving fast has a shocking amount of energy. When such an object impacts the ground, all that energy has to go somewhere.

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

#27

Post by cosmicgadget »

Thinking about this one (https://theaviationist.com/2025/02/12/ea-18g-growler-crashes...), it seems like after ejection you'd want the plane to lawn dart whenever possible. It allows the pilot to know if it is an okay place to ditch and it minimizes the reverse engineering risk.

I imagine there is a good reason this isn't the way things are though.

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

#28

Post by cosmicgadget »

yjftsjthsd-h wrote: post #6
darkhorn wrote: 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.

Not my wheelhouse, but doesn't that involve packing the aircraft with explosives, and wouldn't that involve risk of blowing up if someone else shoots you? Or is there some better way to self-destruct?

There are probably a number of clever and failsafe ways to divert jet fuel somewhere that would destroy the plane on command.

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

#29

Post by tekla »

RobotToaster wrote: post #22
SoftTalker wrote: post #9

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.

Planes that keep flying after an ejection do happen https://en.wikipedia.org/wiki/Cornfield_Bomber https://www.marinecorpstimes.com/news/your-marine-corps/2024...

These are not equivalent.

The first one, the Airplane was in an uncontrolled spin, the ejection happened to fix it.

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