The Vultee engineering team decided early in the design process to build the XA-41 (company Model 90) around the 3,000 hp
Pratt & Whitney R-4360 Wasp Major four-row, 28-cylinder
radial engine. The Model 90's large tapered wing resembled that of
Vultee Model 72 – a two-seat attack aircraft/dive bomber better known as the
Vultee Vengeance (A-31/A-35) – including a straight leading edge, forward-swept trailing edge, and pronounced dihedral on the outer wing panels. Designed to carry both a large internal load and external stores, the XA-41 was large for a single-engine aircraft. The single-place
cockpit, set in line with the wing root, was 15 ft (4.6 m) off the ground when the airplane was parked. As operational priorities shifted during its development phase, the original order for two XA-41 prototypes was cancelled, although the USAAF pressed for the completion of one prototype as an engine testbed for the R-4360 (the same engine used by the
Boeing B-50 Superfortress). ==Operational history==