The XP-42 was a modification of the fourth production P-36A (S/N 38-004) and tested the use of streamlined engine cowling to reduce the drag of a radial engine. The long tapered cowling had a cooling air scoop under the engine and carburetor air scoops on top. An extension shaft was necessary to drive the propeller which had a large spinner to further reduce drag. The cowling didn't significantly reduce drag and the engine had continuing cooling problems even though numerous cowlings were tested.
The XP-42, late in its test life, was fitted with a moveable horizontal stabilizer similar to a modern jet's stabilator and flown to gather test data on the modification.
Fourth P-36A mod.; new nose; engine change
TECHNICAL NOTES: Armament: None Engine:Pratt & Whitney R-1830-31 of 1,050 hp Maximum speed: 315 mph Cruising speed: 286 mph Range: 730 miles (105 gal.)/1200 miles with aux. tanks (161 gal.) Span: 37 ft. 4 in. Length: 30 ft. 3 in. Height: 12 ft. 0 in. Weight: 4,818 lbs. empty/5,920 lbs. gross