The Payen 49 was the first French delta wing aircraft and made its first flight on January 22, 1954. The 300 subsequent research flights of the aircraft were used to check the performance of the delta wing and the "crocodile" rudder, which served both for steering and as an airbrake. The data generated by these research flights was studied for the Concorde prototype development and also Rockwell International for the Space Shuttle.

This aircraft is preserved in the Musee de l'Air at Le Bourget. It was an experimental delta wing design, the sole example built and which first flew on 22nd January 1954.

The Payen Katy was completed in 1954. It was a dimunitive experimental delta with fixed undercarriage powered by a 330 lb.s.t. Turbomeca Palas. It is seen at the 1957 Paris Air Salon and is now displayed nearby in the Musee de l'Air.

This experimental delta-winged aircraft first flew in 1954, powered by a small Turboméca Palas turbojet.