Hall PH

In December 1927, the U.S. Navy placed a contract with the Hall Aluminum Aircraft Corporation of Bristol, Pennsylvania for a developed version of the Naval Aircraft Factory PN-11, which itself could trace a development history back to the Felixstowe F.5 flying boat of World War I. The resultant prototype, the XPH-1, first flew in December 1929. The XPH-1 had identical wings and a similar metal hull to that of the PN-11, but was fitted with a large single fin and rudder. It was powered by two Wright Cyclone radial engines and accommodated its two pilots side by side in an open cockpit, with cockpits for gunners in the nose and behind the wings. The Coast Guard later ordered seven PH-2 aircraft, similar to the PH-1 but with armament removed, and seven PH-3 units with armament reinstated and a fully enclosed cockpit for the pilots. ==Operational history==

Delivery of the PH-1 commenced in October 1931, Production of the PH recommenced in June 1936 to meet an order for seven PH-2s for the Coast Guard. In 1939 the Coast Guard ordered an additional seven PH-3 aircraft; they entered service in 1941. The Hall flying boats were used by the Coast Guard for search and rescue duties and were fitted with specialized equipment for this role. Following the Japanese attack on Pearl Harbor and the United States entry into World War II, the remaining PHs were painted in U.S Navy Sea Grey to replace the previous silver paint, armed, and used for anti-submarine patrols (particularly during the Operation Drumbeat U-boat attacks off the East coast of the United States in 1942) as well as continuing search and rescue operations. The Coast Guard continued operating the PH-2 and -3 until 1944. ==Variants==

;XPH-1 :Prototype. Two Wright R-1750 engines. One built. ;PH-1 :Production version for U.S. Navy. Partly enclosed cockpit for pilots. Two Wright R-1820-86 engines in short-chord Townend ring cowlings. Nine built. ;PH-2 :Version for U.S Coast Guard. Two Wright R-1820F-51 engines. Armament omitted. Seven built. ;PH-3 :Improved version for Coast Guard. Long Chord NACA cowlings. Revised enclosed canopy. Seven built. ==Operators==

; • United States Coast Guard • United States Navy ==Specifications (PH-3)==