The P4Y-1 Corregidor is a flying boat, model 31 was laid down in 1938 and was intended for both military and commercial use. The aircraft had an all-metal structure with a highly efficient, so-called "Davis wing", which was later used in the Liberator B-24. The wing had retractable floats on its lower surface. The power plant consisted of two new 18-cylinder two-row radial Wright Cyclone R-3350 engines, 2300 hp, 1715 kW. The civilian version of the aircraft could accommodate 52 passengers or berths for 28 passengers.

The prototype Model 31 took off for the first time on May 5, 1939, demonstrating excellent performance. With America's entry into World War II following the Japanese attack on Pearl Harbor on December 7, 1941, and upon completion of testing, the US Navy acquired a prototype, designated XP4Y-1. The nose and tail of the prototype underwent changes, a turret mount was installed on top of the fuselage, and a distant patrol boat under the wing could carry bombs up to 4,000 pounds (1,820 kg).

A production order for 200 P4Y-1 units was placed in October 1942 at a new aircraft plant in New Orleans, Louisiana. Delays in prototype production and a shortage of Wright Duplex Cyclone engines (required to power the B-29 Superfortress) led to the cancellation of the production order.

Photo	Description
	Drawing C-87A Corregidor
	XP4Y-1 in flight

Bibliography

• "Encyclopedia of military engineering" /Aerospace Publising/
• "American warplanes of World War II" /under cor. David Donald/