 During the trials, the "Armée de l'Air" radically altered the specifications for fighter and bomber aircraft, virtually eliminating the attack category.This change jeopardized future development of the "Grognard" as the unpressurized airframe was not readily adaptable to other missions.Although a dedicated "all-weather" fighter variant with a radar in the nose, the SE.2421 was planned, a definitive attack variant, the SE.2418 would have used two x 2, 850 kgp (6,2850 lb st) Rolls-Royce Tays with an anticipated performance that included a maximum speed of at sea level.