In early 1935, the US Matériel Division announced a design competition for single-seat fighters to replace the Boeing P-26 Peashooter, then the most advanced aircraft equipping Army Air Corps Pursuit Groups. Manufacturers were invited to submit private venture prototypes for evaluation at Wright Field beginning on 27 May 1935. Initially, three companies decided to enter prototypes in the forthcoming competition: the Curtiss Wright Corporation, which designed its Model 75, the prototype of the P-36 and H75 series; the Seversky Aircraft Corporation which planned to develop a single-seat variant but initially delivered a two-seat prototype, the SEV-2XP, the forebear of the P-35 series; and the Northrop Corporation, which proposed its Model 3A.

To obtain the necessary performance, while hastening the development of the new aircraft, an engineering team led by Ed Heinemann decided to design a retractable undercarriage variant of the of the XFT-1/XFT-2 naval fighter prototype. In spite of this time-saving approach, the Northrop 3A was too late to be delivered to Wight field and the Matériel Division decided to adjourn the competition until August 1935 rather than award a production contract to Curtiss whose Model 75 had been the only entry available on the specified date. However, the stroke of luck which appeared to give a new lease of life to the Northrop 3A was of short duration.

The Northrop 3A (XP-948, c/n 44), powered by a 750-hp Pratt & Whitney Twin Wasp R-1535-A56 fourteen-cylinder radial driving a three-blade propeller, was completed in July 1935. the aircraft was finished in contemporary Air Corps colors, blue fuselage with yellow wings and empennage. The aircraft was unarmed, but had provision for two fuselage-mounted 0.3-inch 0.50-inch machine-guns. After completing preliminary manufacturer’s trials at Mines Field (now LAX), the 3A was ferried to Wight Field in July 1935. However, limited evaluation by Air Corps personnel confirmed the Northrop test pilot’s report that the aircraft was rather unstable and prone to spinning. Accordingly, these 3A was returned to Mines Field were Northrop hoped to find some quick solution to the stability problem before entering the aircraft in the August 1935 competition trials. Intent on testing the modifications made to the aircraft before its scheduled return to Wight Field, First Lieutenant Frank Scare took off on 30 July 1935, for a test flight over the Pacific and failed to return. No trace of the Northrop 3A or its pilot were ever found.

The loss of the prototype effectively removed Northrop from consideration as supplier of the next generation of fighter aircraft for the Army Air Corps. Consequently, to recoup some of its investment in the project, the company sold its design to Chance Vought Aircraft which developed it into the equally unsuccessful V-141 and V-143.
Specifications:
Northrop Model 3A
Dimensions:
Wing span: 34 ft 6 in (10.21 m)
Length: 22 ft 3 in (7.78 m)
Height: 9 ft 1 in (2.77 m)
Weights:
Operational: 3,900 lb (1,769 kg)
Performance:
Maximum Speed: 270 mph (434 km/h)
Powerplant:
One 700 hp (592 kW) Pratt & Whitney SR-1535-6 Twin Wasp Junior engine.
Armament:
One .30 caliber and one .50 caliber fuselage mounted machine-guns.