In the late 1940s and early 1950s, the French aviation pioneer Louis Charles Breguet developed a concept for a short takeoff and landing (STOL) aircraft using four free-turbine turboshaft engines to drive a common powershaft, which, in turn drove four oversize propellers, which were evenly spaced along the leading edge of the wing with large, full-span, slotted flaps, with the arrangement known as "l'aile soufflée" or blown wing.

An initial, experimental prototype, powered by four Turbomeca Turmo II engines, the Breguet 940 Integral, first flew on 21 May 1958,[1] and was used to prove the concept, demonstrating excellent short field performance.

[2] Testing of this prototype resulted in an order for four improved production aircraft, the Breguet 941S for the French Air Force, first flying on 19 April 1967.

McDonnell Douglas continued these efforts, using a production 941S for limited passenger operations for two months in 1968 with Eastern Air Lines between busy urban centers in the northeast U.S.[5][9] The following year, this same aircraft was tested by American Airlines and then by the Federal Aviation Administration to evaluate the STOLport concept for operation from small city airports.

[10] Despite these tests, the company found that airlines were primarily interested in operating jets from conventional airports, and did not embrace the novel STOLport concept; no sales resulted and none of the proposed upgraded versions left the drawing boards.