1955 aircraft ditching into the Pacific Ocean
Pan Am Flight 845/26 was a four-engined Boeing 377 Stratocruiser named "Clipper United States" and registered as "N1032V". It departed Portland International Airport in Oregon on a flight to Honolulu International Airport in Hawaii on March 26, 1955. The aircraft was en route and about off the Oregon coast when at 11:12 Pacific Standard Time the No. 3 engine and propeller tore loose from the wing causing a loss of control. The aircraft was ditched. 
The aircraft floated for twenty minutes before sinking in of water. Approximately two hours after the aircraft ditched, the United States Navy attack transport arrived on the scene and rescued the 19 survivors. Four people died.
The probable cause was failure of No. 3 propeller which caused the engine to detach and the aircraft to become uncontrollable.
The experience provided lessons that helped prevent any casualties in another ditching the following year, when Pan Am Flight 6 sank between Honolulu and San Francisco.
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