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They talk about it as some kind of feature to save pilots, but what they're describing is just how a normal fly by wire system works. If you are in straight and

They talk about it as some kind of feature to save pilots, but what they're describing is just how a normal fly by wire system works. If you are in straight and level flight and don't provide any inputs, it will remain in straight and level flight. That doesn't just apply to the F-35, it's the same for a regular A320 family passenger jet and has been for more than 30 years.

euroderf 3y ago
But if the pilot has ejected, shouldn't it go into a circular holding pattern?
- Arrath 3y ago
  Why not a loop, to allow the pilot to re-enter the craft after taking out their pursuer? /s https://www.youtube.com/watch?v=k-wFI9vTqto https://www.youtube.com/watch?v=k-wFI9vTqto
- BuyMyBitcoins 3y ago
  I’m envisioning a team of software engineers and a product manager balking at the idea that they would need to implement a feature meant to save the airframe after the pilot ejects. “Who’s gonna need that? If the pilot ejects the thing is a lost cause and it’s just gonna crash anyways. Besides, do you know how hard that would be to implement? We don’t have the time. Anything that happens with the autopilot after ejection is out of scope.”
- t0mas88 3y ago
  The flight control system isn't aware of the ejection nor any navigation settings. It's not an autopilot, only a stability system that remains perfectly stable if nobody provides inputs. On autopilot it would be different. If the right mode is enabled it will keep flying the programmed route until the end of that route. Then at the end of the route it will either continue straight ahead on the last heading or enter a holding pattern at that position. Depends on what was programmed in the navigation database. But in the end it doesn't really matter after an ejection, it will run out of fuel and crash.
  - iancmceachern 3y ago
    It's within the realm of possibility to have it self land after an incident. They certainly can't now, but we have the technology if we wanted. Logically, I think the main thing is there is typically a reason a pilot is ejecting. As the saying goes, a pilot does not eject from a good airplane. The assumption there being if the plane could be landed, it would have been landed by its pilot. If the pilot ejected, it's because they're was something gravely wrong, and therefore is not of great value to put a lot of effort into doing fancy tricks in a about to crash airplane.
pxeger1 3y ago
Surely having a hole in the roof because of the ejection changes the aerodynamics significantly. I don't really know anything about how planes work, but wouldn't that change its trajectory if the controls are all left the same?
- lm28469 3y ago
  It's smart enough to compensate for it. Otherwise it wouldn't work with wind or air of different temperature/density "if the controls are all left the same" Just like a car with speed limiter can maintain speed when you go from flat to incline, provided the engine is good enough
- dingaling 3y ago
  Even prior to FBW, aircraft which had been vacated by their pilots contentedly cruised on with a big hole in the roof. A Hunter was abandoned by its RAF pilot in the 1960s and proceeded to land itself on the runway, whilst a MiG-23 and a Harrier flew without their drivers until fuel exhaustion in the 1980s.
- iancmceachern 3y ago
  That's the whole point of fly by wire. In an old school plane yes, the pilot would have to compensate for this because the pilot is in the feedback loop. In fly by wire systems there is an IMU with gyros, accelerometers and magnetometers. The plane servos itself to a heading and velocity, and the pilot provides imput that changes the target position in space, and then the plane decides how to hey to the target position.

euroderf 3y ago

But if the pilot has ejected, shouldn't it go into a circular holding pattern?

Arrath 3y ago
Why not a loop, to allow the pilot to re-enter the craft after taking out their pursuer? /s https://www.youtube.com/watch?v=k-wFI9vTqto https://www.youtube.com/watch?v=k-wFI9vTqto
BuyMyBitcoins 3y ago
I’m envisioning a team of software engineers and a product manager balking at the idea that they would need to implement a feature meant to save the airframe after the pilot ejects. “Who’s gonna need that? If the pilot ejects the thing is a lost cause and it’s just gonna crash anyways. Besides, do you know how hard that would be to implement? We don’t have the time. Anything that happens with the autopilot after ejection is out of scope.”
t0mas88 3y ago
The flight control system isn't aware of the ejection nor any navigation settings. It's not an autopilot, only a stability system that remains perfectly stable if nobody provides inputs. On autopilot it would be different. If the right mode is enabled it will keep flying the programmed route until the end of that route. Then at the end of the route it will either continue straight ahead on the last heading or enter a holding pattern at that position. Depends on what was programmed in the navigation database. But in the end it doesn't really matter after an ejection, it will run out of fuel and crash.
- iancmceachern 3y ago
  It's within the realm of possibility to have it self land after an incident. They certainly can't now, but we have the technology if we wanted. Logically, I think the main thing is there is typically a reason a pilot is ejecting. As the saying goes, a pilot does not eject from a good airplane. The assumption there being if the plane could be landed, it would have been landed by its pilot. If the pilot ejected, it's because they're was something gravely wrong, and therefore is not of great value to put a lot of effort into doing fancy tricks in a about to crash airplane.

pxeger1 3y ago

Surely having a hole in the roof because of the ejection changes the aerodynamics significantly. I don't really know anything about how planes work, but wouldn't that change its trajectory if the controls are all left the same?

lm28469 3y ago
It's smart enough to compensate for it. Otherwise it wouldn't work with wind or air of different temperature/density "if the controls are all left the same" Just like a car with speed limiter can maintain speed when you go from flat to incline, provided the engine is good enough
dingaling 3y ago
Even prior to FBW, aircraft which had been vacated by their pilots contentedly cruised on with a big hole in the roof. A Hunter was abandoned by its RAF pilot in the 1960s and proceeded to land itself on the runway, whilst a MiG-23 and a Harrier flew without their drivers until fuel exhaustion in the 1980s.
iancmceachern 3y ago
That's the whole point of fly by wire. In an old school plane yes, the pilot would have to compensate for this because the pilot is in the feedback loop. In fly by wire systems there is an IMU with gyros, accelerometers and magnetometers. The plane servos itself to a heading and velocity, and the pilot provides imput that changes the target position in space, and then the plane decides how to hey to the target position.