Aircraft flaps?

Question

When landing do aircraft usually have their flaps fully down or just a little bit down? Does having the flaps fully down on landing create too much lift to descend to the runway safely even at slow landing speeds?

Answer 1

idk, it depends.

Answer 2

Elana is right. Your question is difficult to answer without knowing which type of aircraft and under runway,weather,etc. conditions

Small aircraft(Cessna,Piper) don't usually use flaps. That doesn't mean they don't use them. Large airliners usually use the flap position that is most fully down as you say.

The higher flap settings do create lift but they also generate a lot drag. It would take a short lesson in aerodynamics to explain the many variables.

Answer 3

It's a good question. And yes, for the most part they should be fully down when landing. You can never have too much lift. Sooner or later, gravity rules but flying as slow as possible during landing is safest. If bad things happen, they happen slower.

Having said that, there are times when less than full flaps is best such as gusty winds where more control is desirable. And in the 727 that you see me sitting in we rarely land with full flaps. This baby has so much lift with slats and flaps full it's ridiculous. Fun to do at times though.

And Ozzie, tell me you did not meant to say that you don't normally use full flaps in a cessna or a piper. C'mon man, you should know better than that. At least I hope you do. I've flown 72 aircraft types, small and large, and not one AFM has ever suggested anything but full flaps for a normal landing. Those that have flaps anyway. Helicopters and some gliders I've flown don't.

Answer 4

The flaps are lowered about 5-10 degrees shortly after descent. Upon "final approach", they are then lowered fully (about 30 percent).

Answer 5

Depends on the aircraft.

It also depends on the weather conditions.

We used to land Cessna 152's with full flaps (30") with all but the gustiest of weather - in which case it was 20" or (yikes) 10".

"Too much lift" isn't really possible, since you can back off on the power.  However, with so much lift relative to AIRSPEED,  you're more at the whim of wind shear.  That is, if the airspeed is very low, you're more likely to be effected by a massive change in wind velocity.

If you're going 90 kts and the 10 kts headwind suddenly stops, all of a sudden, you're only going 80 kts.  Survivable.  If you're going 65 kts and the same happens, you may be below the stall speed of the aircraft.  Not generally a good thing when you're on final.

Answer 6

In most cases the flaps of an aircraft are fully down for landing.  This increases the lift created by the wing and thus lowers the speed you can land at.