Fire, probably. But also, how complicated would you make the system if you needed to prevent certain switches from working during certain times of flight? At some point... we're all just in the hands of the people in the cockpit.
Sure, but you can open the door, pull the handbrake, or turn the wheel so hard you lose control of the vehicle. These are all similarly preventable, but maybe not worth the risk of being unable to open the door, brake or steer if the safety mechanism fails closed, or if your situation is outside the foresight of its designer.
Also, you don't need multiple certifications and 1500 hours of experience to drive a car.
A friend did exactly that in a manual transmission, doing 100km/h.
She was mad and said she has to jam it hard ( going for 5th and missed), but it went into reverse. And the gearbox literally hit the road when she let out the clutch.
There may be a good reason to cut fuel to one engine shortly after takeoff.
You could have a system that prevents both switches being thrown, and only in the specific window after takeoff, but you’ve also now added two additional things that can fail.
Engine overheating even on idle thrust (if this happens after V1, you would idle it and continue the takeoff anyway; you are beyond the point at which you can safely abort).
Engine oil leak has drained the oil completely and the engine is about to fail catastrophically (unlikely on takeoff but you never know).
Engine is on fire (out of all of the things that can go wrong with an engine during takeoff, this is very likely).
Engine has blown up (ditto).
Engine is missing from the aircraft (not likely, but engines have fallen from planes on takeoff before).
Debris / Ash / etc is in the engine (not likely).
Severe fuel leak (not something I'd worry about during takeoff).
Disable the fuel system cutoff controls during the takeoff climb phase of flight. Once the aircraft loses contact with the runway, these controls shouldn't function without tripping certain thresholds (speed & altitude), or following a two-man procedure that is physically impossible to execute solo. In any other flight regime, the controls function as originally designed.
The danger of a burning engine is irrelevant if you are heading into terrain.
Now you created a fuel system cutoff control inhibition system which may malfunction in its own ways, e.g., refuse to cut off fuels from a burning engine because it thinks the plane is too low due to faulty altimeter reading.
I don't think so. A moderately hard landing with an engine(s) smoldering because they were on fire but had their fuel cut off is probably survivable for most of the passengers. A moderately hard landing with the engine(s) a raging inferno pouring burning fuel all over the place because the fuel couldn't be cut off or took too long to do so is much less survivable.
Putting complex and fallible restrictions on safety-critical controls like fuel cutoff is usually a bad idea overall.
> The danger of a burning engine is irrelevant if you are heading into terrain.
Not quite. When you hit the ground you do not want any fuel leaks or hot surfaces as much as possible. That is why for example engines are shutdown when doing an emergency belly landing, to try abd prevent the airplane from bursting into flames.
As long as you also eliminate the possibility of maintenance problems and defects in automation, and have perfect microscale weather forecasts, and still have overrides for the human safety pilot that can still... wait a minute.
Fire, probably. But also, how complicated would you make the system if you needed to prevent certain switches from working during certain times of flight? At some point... we're all just in the hands of the people in the cockpit.
I can't put my car into reverse gear while driving down the freeway.
Sure, but you can open the door, pull the handbrake, or turn the wheel so hard you lose control of the vehicle. These are all similarly preventable, but maybe not worth the risk of being unable to open the door, brake or steer if the safety mechanism fails closed, or if your situation is outside the foresight of its designer.
Also, you don't need multiple certifications and 1500 hours of experience to drive a car.
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A friend did exactly that in a manual transmission, doing 100km/h.
She was mad and said she has to jam it hard ( going for 5th and missed), but it went into reverse. And the gearbox literally hit the road when she let out the clutch.
There’s no good reason to do that.
There may be a good reason to cut fuel to one engine shortly after takeoff.
You could have a system that prevents both switches being thrown, and only in the specific window after takeoff, but you’ve also now added two additional things that can fail.
You also can't reverse a plane while flying it...
This is a rather odd comparison. You can slam the brakes, yank the steering week, and do all sorts of things to intentionally make the car crash.
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Remember the "surging" incidents where the driver insisted he was stepping on the brake but was actually stepping on the gas?
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You can turn the ignition off. The reversers will not unlock on an airliner that's airborne either.
Completely uneducated guess but if one engine bursts into flames you might want to kill the fuel.
Engine overheating even on idle thrust (if this happens after V1, you would idle it and continue the takeoff anyway; you are beyond the point at which you can safely abort).
Engine oil leak has drained the oil completely and the engine is about to fail catastrophically (unlikely on takeoff but you never know).
Engine is on fire (out of all of the things that can go wrong with an engine during takeoff, this is very likely).
Engine has blown up (ditto).
Engine is missing from the aircraft (not likely, but engines have fallen from planes on takeoff before).
Debris / Ash / etc is in the engine (not likely).
Severe fuel leak (not something I'd worry about during takeoff).
Probably other reasons I can't think of.
Suggest a system that would prevent this, but only this, without causing other risks.
Disable the fuel system cutoff controls during the takeoff climb phase of flight. Once the aircraft loses contact with the runway, these controls shouldn't function without tripping certain thresholds (speed & altitude), or following a two-man procedure that is physically impossible to execute solo. In any other flight regime, the controls function as originally designed.
The danger of a burning engine is irrelevant if you are heading into terrain.
Now you created a fuel system cutoff control inhibition system which may malfunction in its own ways, e.g., refuse to cut off fuels from a burning engine because it thinks the plane is too low due to faulty altimeter reading.
I don't think so. A moderately hard landing with an engine(s) smoldering because they were on fire but had their fuel cut off is probably survivable for most of the passengers. A moderately hard landing with the engine(s) a raging inferno pouring burning fuel all over the place because the fuel couldn't be cut off or took too long to do so is much less survivable.
Putting complex and fallible restrictions on safety-critical controls like fuel cutoff is usually a bad idea overall.
> The danger of a burning engine is irrelevant if you are heading into terrain.
Not quite. When you hit the ground you do not want any fuel leaks or hot surfaces as much as possible. That is why for example engines are shutdown when doing an emergency belly landing, to try abd prevent the airplane from bursting into flames.
Sounds good, but I'm not sure I trust Boeing outsourced software developers to implement that absolutely correctly.
Another comment mentioned that with an Airbus you first have to move the thrust lever to idle before you're able to cutoff the fuel.
That seems sensible and relatively easy to implement without screwing it up.
At least an audible alert.
Exactly
Yeah that would have completed prevented this scenario /s
> Why can the pilot shut off the fuel during takeoff?
Engine failure during takeoff.
Engine fire.
What you are really asking is: would we, the passengers, be safer without human pilots?
Eventually, yes. Soon? Maybe.
Dog and a pilot. The pilot is there to make sure everything is ok and the dog is there to bite the pilot if he tries touching anything
As long as you also eliminate the possibility of maintenance problems and defects in automation, and have perfect microscale weather forecasts, and still have overrides for the human safety pilot that can still... wait a minute.