Landing technique differences
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Landing technique differences
I am interested in the aerodynamic and practical reasons for the differences in landing technique between two types I fly. Bombardier on both the Global and the Lear series teach that thrust levers should be closed at 50ft and then the aircraft flown on with a gentle flare to check the rate of descent.
Boeing advise that the 737 should be flown on, but with the thrust levers slowly closed simultaneously with the commencement of the flare to reach idle roughly upon touchdown.
Obviously landing technique varies slightly with wind conditions, and one uses power as much as pitch changes to adapt in rough conditions, but I would like to know why the technique is so different (as if on a medium jet one were to bring thrust to idle at 50ft the resulting landing would be pretty abrupt). Is it simply due to momentum differences between 10t bizjet and a 60t medium jet, the difference between the laminar flow fairly clean wings of the Global/Lear and the large number of lift devices and big drag flaps of the 737, differences in ground effect, or other factors? Or is it that tailstrike is not a factor in the Lear or the Global, meaning that one has more scope to use larger pitch changes close to the ground to mitigate sink?
Boeing advise that the 737 should be flown on, but with the thrust levers slowly closed simultaneously with the commencement of the flare to reach idle roughly upon touchdown.
Obviously landing technique varies slightly with wind conditions, and one uses power as much as pitch changes to adapt in rough conditions, but I would like to know why the technique is so different (as if on a medium jet one were to bring thrust to idle at 50ft the resulting landing would be pretty abrupt). Is it simply due to momentum differences between 10t bizjet and a 60t medium jet, the difference between the laminar flow fairly clean wings of the Global/Lear and the large number of lift devices and big drag flaps of the 737, differences in ground effect, or other factors? Or is it that tailstrike is not a factor in the Lear or the Global, meaning that one has more scope to use larger pitch changes close to the ground to mitigate sink?
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I don't know the really answer, but just thinking about it I would say its a combination of the things you mentioned as well as where the engines are.
The weight differences means of course that there is going to be more momentum, so if you close the thrust levers at 50' on a 737 you are going to have to increase the flare, which means more chance of a tail strike. On top of this, when you reduce thrust in a 737 you get a pitch down reaction, which is going to make things worse.
The weight differences means of course that there is going to be more momentum, so if you close the thrust levers at 50' on a 737 you are going to have to increase the flare, which means more chance of a tail strike. On top of this, when you reduce thrust in a 737 you get a pitch down reaction, which is going to make things worse.
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my guess is this
on the boeing, cut the power and th enose drops
on the bomb, cut th epower and nothing happens
tail vs underwing mounts
I do think the boeing way is right. the other way is probably the best way to get a short field landing
on the boeing, cut the power and th enose drops
on the bomb, cut th epower and nothing happens
tail vs underwing mounts
I do think the boeing way is right. the other way is probably the best way to get a short field landing
