I get that the trailing edge plain flap has disadvantages (like tendency to separate flow as I read on a question on here)

But what’s so bad with the fowler flap? Aren’t they like really efficient and used on jet aeroplanes?enter image description here


1 Answer 1


Yes, flowler flaps (specifically slotted fowler flaps) are used on virtually all airliners because they provide the best efficiency of all the various flap designs.

The major downside is that they are more complex, and therefore expensive to both install and maintain. But in most large aircraft it's a worthwhile investment.

In small aircraft you may run into the problem of fowler flaps being too efficient. They will have less form drag than a plain flap, resulting in a shallower approach, and also after touchdown you may not have enough weight on the wheels for effective braking, without the help of spoilers and reverse thrust.

  • 1
    $\begingroup$ Their complexity (in addition to making them expensive) also makes them heavy. $\endgroup$ Apr 6 at 23:00
  • $\begingroup$ Do they still have gaps in between the bits please? I mean like a normal flap does please? $\endgroup$ Apr 7 at 15:12
  • $\begingroup$ @FlightWatcher -- those "gaps between the bits" are really the basic characteristic of a Fowler flap. Not sure which gaps you would be referring to in the case of a "normal flap". $\endgroup$ Apr 7 at 16:22

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .