In 1930, Detroit Aircraft Corporation undertook a private venture to develop a new fighter ("pursuit aircraft" in contemporary terminology) for US Army Air Corps based on the successful Lockheed Altair transport plane.

Early testing was sufficiently impressive to generate an order for five Y1P-24 fighters and four Y1A-9 attack aircraft intended to replace the Berliner-Joyce P-16.

The A-9 differed in having four forward-firing machine guns, underwing racks for bombs, and a V-1570-27 engine better low-altitude performance.

[3] Shortly after, in October 1931, events in the Great Depression forced Detroit Aircraft into bankruptcy with Lockheed following suit in June 1932.

[2] Although Lockheed was resuscitated by a group of investors only five days after it closed doors, the financial hardships had taken their toll and the P-24/A-9 project was cancelled with no aircraft built beyond the original prototype.