What you are saying is true. It is for this reason that some people retract
flaps after touchdown when doing short field landings. However, the lifting
effect of flaps after touchdown is pretty minor. The lift decreases as the
square of the airspeed. So lift drops off very fast as you decelerate.



"Ramapriya" wrote in news:1103888251.673617.173970
@f14g2000cwb.googlegroups.com:

Hi folks,

I've always seen spoilers and flaps being deployed fully upon landing.
While the reason for spoilers is straightforward, I haven't yet figured
why flaps are deployed too.

Isn't the landing roll the time when you'd be wanting all the load of
the craft to be on the main wheels, which is where the brakes are,
instead of creating lift whereby the load gets transferred onto the
wings and possibly lessening the braking effect? I know the plane would
be decelerating all the time with the engines throttled back fully and
even the forward thrust depolyed, perhaps, yet why create any lift
possibility at all? Wouldn't braking be more effective with no flaps
deployed? Or does the drag produced by the flaps compensate for the
lift?

I suspect I've missed something really fundamental )
Ramapriya