Experimental German plane with suction at the flap knee (flew 1940):
Mixed suction and blowing on a French Breguet Vultur (flew 1956):
U.S. L-1 liason plane with suction flaps (flew 1944):
U.S. XC-123D with suction inboard, blowing outboard (flew 1955)
U.S. F-86F with leading edge suction (flew 1953)