Hi Jan, I noticed that if you lose both engines on one side of the A380 it is impossible to make the plane fly straight, it just stalls and falls.
A380
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EduMunox -
March 1, 2025 at 8:18 PM -
Thread is Resolved
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Hi Jan, I noticed that if you lose both engines on one side of the A380 it is impossible to make the plane fly straight, it just stalls and falls.
Hm yes, do you have any data on how it should look like in the real aircraft though?
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Hm yes, do you have any data on how it should look like in the real aircraft though?
I mean that in real life it would be possible to correct the thrust asymmetry with the rudder and ailerons but in the simulator it is impossible to correct that yaw.
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I mean that in real life it would be possible to correct the thrust asymmetry with the rudder and ailerons but in the simulator it is impossible to correct that yaw.
In the real world, below a certain speed it would also become impossible, depending on the amount of thrust. At higher speed the control surfaces are more effective.
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Is certification based only on losing one engine? I knew all this stuff in the previous millennium but I can’t remember it any more and couldn’t be bothered to find and dust off the books.
I think flying with two engines off on one side might get a lower performance category allowance, something less than climbing away with big safety margins following losing two engines just after reaching V1 speed. I do not know. If it happened in the cruise the plane might be expected to slowly descend down to the height at which the speed and level can be maintained on the remaining power.
The Aerofly mobile 747 on two engines on one side climbs at 500 fpm at 280 knots passing 15,000 feet. That is with 5 degrees of bank into the live engines with a trace of ‘ball’ on the same side. That looks pretty good to me. In the descent with reduced power there would be a far greater control margin. With the 380 in the same conditions it did 800 fpm at 20,000 feet. All were under control.
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- Official Post
Is certification based only on losing one engine? I knew all this stuff in the previous millennium but I can’t remember it any more and couldn’t be bothered to find and dust off the books.
I think flying with two engines off on one side might get a lower performance category allowance, something less than climbing away with big safety margins following losing two engines just after reaching V1 speed. I do not know. If it happened in the cruise the plane might be expected to slowly descend down to the height at which the speed and level can be maintained on the remaining power.
For certification the worst case single engine failure defines the minimum control speed in the air. For quad jets that's one outboard engine but not two on the same side. The minimum speed for dual engine failure one one side is not tested and could be significantly higher, higher than VMO even, hehe. It might then be necessary to reduce thrust on the remaining outboard engine to regain control. But I've never seen such a test in the real world. I know that some 747s have landed with two engines one one side failed but there have also been cases where they lost control and crashed. So it's hard to say what the real A380 might do. It's outside the certified envelope, pretty sure.
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Hi. I thinks this situation happens with the 320 family when taking off with one engine (like simulating an engine failure) the plane is imposible to fly despite applying the correct rudder.
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Hi. I thinks this situation happens with the 320 family when taking off with one engine (like simulating an engine failure) the plane is imposible to fly despite applying the correct rudder.
Vmca - I was doing some V1 cuts with the A319 this weekend, as long as I kept the speed above Vmca the aircraft flew fine with rudder trim. Am also very impressed with how the aircraft behaves in a stall situation in direct law.
