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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)

#41

Post by WheatMillington »

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.

Do you realise we're dealing with humans? Humans who make decisions based on a multitude of factors, or sometimes none at all?

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

#42

Post by the__alchemist »

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.

Not necessarily. For example, you'd eject if unable to get as safe landing configuration.

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

#43

Post by SoftTalker »

WheatMillington wrote: post #41
SoftTalker wrote: post #19

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.

Do you realise we're dealing with humans? Humans who make decisions based on a multitude of factors, or sometimes none at all?

Yes, but flying aircraft with ejection seats is demanding work and few humans are capable or qualified to do it. Most people can barely manage to drive cars safely.

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

#44

Post by appreciatorBus »

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…

If we had the technology to fly the aircraft back to base then there wouldn't be an ejection handle, there would be a "fly the aircraft back to base" button.

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

#45

Post by pdonis »

cluckindan wrote: post #23
pdonis wrote: 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…

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

> About one in 20 ejections results in death

But more than that result in injury. The possible injuries are pretty severe.

> Compare to 20 in 20 jet airplane crashes resulting in death

Crashes if the plane is totally uncontrollable, probably yes.

But there's a lot of gray area in between "totally uncontrollable" and "controllable enough that an autopilot can fly the plane". There are plenty of cases where a pilot was able to make a controlled enough crash that they walked away from it, even though the plane itself was totalled.

And once we get to the point of "controllable enough that an autopilot can fly the plane", the pilot would have no reason to eject--because the plane is controllable enough that the autopilot can fly it. Which means whatever problems exist can't be very severe--or the autopilot would be disengaging, because it needs things to be working pretty well to fly the plane at all. That was the point of my response in the GP to this post.

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

#46

Post by jojobas »

dylan604 wrote: post #17
jojobas wrote: post #13

Earlier quoted context omitted.

Would you go near a plane that's an electronic signal away from blowing itself up? Even if mechanical, warplanes get combat damage, and having a system like that could make a difference between survivable and sure death.

Maybe bring some strong jamming equipment to prevent the electronic signal from being received?

The signal can originate on the plane itself due to a software glitch, stray currents in the grounding skin or whatever. If anything, jammers tend to interfere with the carrier's electronics itself.

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

#48

Post by throwaway173738 »

dragonwriter wrote: post #38
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…

> The plane, after I eject, should do something reasonable. There’s a good chance that it can't, and its not impossible that trying to do something reasonable combined with damage that led to and/or resulted from ejection could make things worse. > starts broadcasting a mayday? Great idea for peacetime over the homeland, maybe a very bad idea for military operations over contested or enemy territory. > crashes into t…

Yeah it’s equivalent to asking what a car should do after a 60mph collision. Probably sit still and try not to catch fire.

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

#49

Post by miki123211 »

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?

You could self-destruct just the software / computers by encrypting everything with a few keys that are easy to destroy.

This is a standard technique for quick and secure data wipes, particularly on e.g. modern SSD drives where a traditional wipe might be incomplete due to wear leveling algorithms.

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

#50

Post by justsomehnguy »

jvanderbot wrote: post #24
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…

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…

To add:

If the flight happens in the Grand Canyon?

A tightly populated Grand Canyon?

Tightly populated, divided by multiple not-so-friendly nations? Which have nuclear weapons?

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