A US Air Force F-35 pilot spent 50 minutes on an airborne conference call with Lockheed Martin engineers trying to solve a problem with his fighter jet before he ejected and the plane plunged to the ground in Alaska earlier this year, an accident report released this week says.
But there are no manual controls on a modern fighter, they are aerodynamically unstable so even if you wanted to implement a manual backup system, it would be impossible. The way modern flight control systems work, is that they take the pilot’s inputs, interpret the desired outcome that the pilot wants from said inputs, and achieve it by calculating the various movements of control surfaces required to achieve the desired outcome. This means the movements of ailerons, rudders, elevators, flaps and engine controls to achieve that, without the pilot being aware of all of this, just that the aircraft is behaving as expected from the control inputs. The system also is constantly adjusting these inputs to keep the aircraft stable and within it’s performance envelope without the pilot’s involvement. Hence why something like an F-35 or B-2 can fly in the first place, and why a Su-35 can pull off spectacular maneuvers.
If you mean a manual override for not going into certain control law configurations, I’m not sure if that can be implemented. The flight control system is constantly “blending” between different flight modes and adjusting based off of data from all the sensors onboard. It’s not a binary thing. While I’m sure there are forms of manual overrides, it’s not that simple. Here the F-35 went into ground control flight laws once 3/5 of the weight on wheels sensors stated that the aircraft was on the ground.
As for using different sensors, airspeed can’t be used as the aircraft could be above V1/rotation speed and still have wheels on the ground during takeoff, or it could be below that speed or below stall speed and still airborne. And I don’t think the altimeter is precise enough to know exactly when each wheel lifts off of the ground either. As for a cutoff that states “if the aircraft is above X speed and Y altitude it’s definitely airborne”, we’ll just be back to square one, once we drop below that cutoff. So it’s not hugely useful either.
Definitely, Marmite Lover is just wrong here to use it as a defense. The technical explanation of computer controlling systems has no impact on the fact that software can put an aircraft in a state without any pilot override.
Keep in mind that the pilot would have had 9 seconds to determine that the problem is being in ground control law, decide to flip the switch, unguard the switch and flip it. Once the aircraft thinks it is on the ground, it begins to actively crash and if the issue isn’t the flight control law, those wasted seconds risk killing the operator.
decide to flip the switch, unguard the switch and flip it
Are you aware of what the F-35 cockpit looks like? It’s mostly a giant touchscreen. What’s all this nonsense about “flipping a switch”? Surely you mean navigate to the correct settings menu.
Because at the start only 1 of the sensors, the one on the nose gear wheel, was stating that the aircraft was on the ground. After multiple touch and go landing attempts, the two main landing gear struts froze as well, and the other sensors also then stated that the aircraft was on the ground. Once that point was reached, only then the aircraft went into ground control flight laws.
When I say modern fighter aircraft don’t have “manual control”, I mean there’s no physical connection between the flight stick and the control surfaces, it all goes through a computer.
Understood, thank you for the explanation. Still think a ‘go to air mode now’ switch on that bug dumb control panel those things have would be a good idea for cases like this.
in the abstract, of course. It’s good there is one less of these shitty death machines.
He didn’t. He was flying for 50 minutes in the normal and correct “fly-by-wire” settings. Then he did two touch and go landings. On the second touch and go the F-35 decided that he was now on the ground. The new fly-by-wire settings were now in ground mode and this made it impossible to fly the plane properly in the air.
Okay. I am confused why he would be in the call then if things were working. And no I am not gonna read this transcript, sorry to ask you questions about it.
Also, wouldn’t a good override for a case like this be: “hey plane, I am not on the ground, resume flight mode you fucking 100+ million dollar piece of shit”? You know, instead of turning the assistance off?
The F-35 is a piece of shit. There were two separate problems.
A. Problem 1 is that the hydraulic fluid froze because of shitty maintenance. It’s not supposed to do that. This caused the landing gear to become stuck in a partially retracted position. The pilot couldn’t land so he called tech support and spent 50 minutes on a conference call.
B. The tech support guys told him to do some touch and go landings to see if that fixes the problem. Basically hitting the landing gear against the runway to see if that fixes it.
C. During the 2nd touch and go landing the F-35 decided it was landed and switch the pilot from the flying controls to the ground controls. These are really only meant for doing stuff on the ground like taxi-ing or starting the take-off. You can’t fly the plane like this so the pilot ejected and the plane crashed.
Yes there should be an override but also that may not have helped in this situation. Once the F-35 decided it was on the ground he would have only a few seconds to figure out the problem, override the system, and pilot his way out of a crash. What would have been useful is an override he could have set up in advance to prevent the F-35 from switching to ground mode regardless of what its sensors tell it. I’m sure Lockheed can code something like that for a few billion dollars.
but in that case, couldn’t the “blend” be altered like a coffee or something? or if that’s a stupid question, couldn’t the weight on wheels sensors be disabled? idk it just seems like there’s a lot of stuff that could have been overridden
But there are no manual controls on a modern fighter, they are aerodynamically unstable so even if you wanted to implement a manual backup system, it would be impossible. The way modern flight control systems work, is that they take the pilot’s inputs, interpret the desired outcome that the pilot wants from said inputs, and achieve it by calculating the various movements of control surfaces required to achieve the desired outcome. This means the movements of ailerons, rudders, elevators, flaps and engine controls to achieve that, without the pilot being aware of all of this, just that the aircraft is behaving as expected from the control inputs. The system also is constantly adjusting these inputs to keep the aircraft stable and within it’s performance envelope without the pilot’s involvement. Hence why something like an F-35 or B-2 can fly in the first place, and why a Su-35 can pull off spectacular maneuvers.
If you mean a manual override for not going into certain control law configurations, I’m not sure if that can be implemented. The flight control system is constantly “blending” between different flight modes and adjusting based off of data from all the sensors onboard. It’s not a binary thing. While I’m sure there are forms of manual overrides, it’s not that simple. Here the F-35 went into ground control flight laws once 3/5 of the weight on wheels sensors stated that the aircraft was on the ground.
As for using different sensors, airspeed can’t be used as the aircraft could be above V1/rotation speed and still have wheels on the ground during takeoff, or it could be below that speed or below stall speed and still airborne. And I don’t think the altimeter is precise enough to know exactly when each wheel lifts off of the ground either. As for a cutoff that states “if the aircraft is above X speed and Y altitude it’s definitely airborne”, we’ll just be back to square one, once we drop below that cutoff. So it’s not hugely useful either.
This is good info, but it still seems like a manual “I’m actually still in the air” button could be available to influence those algorithms
Definitely, Marmite Lover is just wrong here to use it as a defense. The technical explanation of computer controlling systems has no impact on the fact that software can put an aircraft in a state without any pilot override.
Keep in mind that the pilot would have had 9 seconds to determine that the problem is being in ground control law, decide to flip the switch, unguard the switch and flip it. Once the aircraft thinks it is on the ground, it begins to actively crash and if the issue isn’t the flight control law, those wasted seconds risk killing the operator.
Are you aware of what the F-35 cockpit looks like? It’s mostly a giant touchscreen. What’s all this nonsense about “flipping a switch”? Surely you mean navigate to the correct settings menu.
Oh so it’s even worse than I thought. That’s a surprising lack of guarded switches.
How did the pilot fly it for 50 minutes in that state if manual control is impossible?
Because at the start only 1 of the sensors, the one on the nose gear wheel, was stating that the aircraft was on the ground. After multiple touch and go landing attempts, the two main landing gear struts froze as well, and the other sensors also then stated that the aircraft was on the ground. Once that point was reached, only then the aircraft went into ground control flight laws.
When I say modern fighter aircraft don’t have “manual control”, I mean there’s no physical connection between the flight stick and the control surfaces, it all goes through a computer.
Understood, thank you for the explanation. Still think a ‘go to air mode now’ switch on that bug dumb control panel those things have would be a good idea for cases like this.
in the abstract, of course. It’s good there is one less of these shitty death machines.
everything's computer
That’s actually the most simple and concise way to explain it lol.
He didn’t. He was flying for 50 minutes in the normal and correct “fly-by-wire” settings. Then he did two touch and go landings. On the second touch and go the F-35 decided that he was now on the ground. The new fly-by-wire settings were now in ground mode and this made it impossible to fly the plane properly in the air.
Okay. I am confused why he would be in the call then if things were working. And no I am not gonna read this transcript, sorry to ask you questions about it.
Also, wouldn’t a good override for a case like this be: “hey plane, I am not on the ground, resume flight mode you fucking 100+ million dollar piece of shit”? You know, instead of turning the assistance off?
The F-35 is a piece of shit. There were two separate problems.
A. Problem 1 is that the hydraulic fluid froze because of shitty maintenance. It’s not supposed to do that. This caused the landing gear to become stuck in a partially retracted position. The pilot couldn’t land so he called tech support and spent 50 minutes on a conference call. B. The tech support guys told him to do some touch and go landings to see if that fixes the problem. Basically hitting the landing gear against the runway to see if that fixes it. C. During the 2nd touch and go landing the F-35 decided it was landed and switch the pilot from the flying controls to the ground controls. These are really only meant for doing stuff on the ground like taxi-ing or starting the take-off. You can’t fly the plane like this so the pilot ejected and the plane crashed.
Yes there should be an override but also that may not have helped in this situation. Once the F-35 decided it was on the ground he would have only a few seconds to figure out the problem, override the system, and pilot his way out of a crash. What would have been useful is an override he could have set up in advance to prevent the F-35 from switching to ground mode regardless of what its sensors tell it. I’m sure Lockheed can code something like that for a few billion dollars.
but in that case, couldn’t the “blend” be altered like a coffee or something? or if that’s a stupid question, couldn’t the weight on wheels sensors be disabled? idk it just seems like there’s a lot of stuff that could have been overridden