A U.S. Navy PB-1 (Boeing Model 50) patrol plane, in 1925. The PB designation was first used for the Boeing model 50 flying boat which was built in 1925 for a nonstop flight to Hawaii. The US Navy had designated the aircraft PB-1 and given it serial A6881. The designation PB was the used again for the US Navy version of the B-17 Flying Fortress. On 31 July 1945 the US Navy ordered a single B-17F from the USAAF production line with the designation PB-1 and the BuNo 34106. Former B-17Gs were converted for the US Coast Guard as PB-1Gs and for the USN as PB-1Ws.
Bain News Service
1925
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