Boeing XP-15

The Boeing XP-15 was a prototype monoplane fighter of the United States, the second to be designated a pursuit type, after the Boeing XP-9.

Design and development
This aircraft was essentially a monoplane version of the Boeing P-12, differing in having the lower wing omitted and in having all-metal construction as well as altered ailerons. The XP-15 had a split-axle undercarriage and a tail wheel.

Boeing numbered the craft as its Model 202; while the United States Army accepted it for testing and designated it as XP-15, they never actually purchased it, and it retained its civil registration of X-270V.

Operational history
The XP-15 first flew in January 1930, where it was discovered that the vertical stabilizer (a P-12C type) needed to be larger in order to compensate for the single wing. Initial testing showed a top speed to 178 mph, but with enlarged tail surfaces and a Townend cowling, it recorded 190 mph at 8,000 ft. The aircraft performed poorly, with a poor rate of climb and a high landing speed. The USAAC did not order the aircraft for production and on 7 February 1931, the prototype was destroyed when a propeller blade failed and the engine tore loose from its mounts.

The Navy was offered the similar Model 205. It first flew in February 1930. It was ordered by the US Navy, but by the time flight testing was complete in 1932, other aircraft were ordered instead. It was however, the first monoplane to receive a US Navy designation, XF5B.

Operators

 * 🇺🇸 United States
 * United States Army