PN-9

The PN‑9 was a Navy‑built, single‑engine flying boat created by the Naval Aircraft Factory in the early 1920s to meet the United States Navy’s requirement for a long‑range, ocean‑crossing reconnaissance aircraft. First flown in June 1921, the PN‑9 was a wooden, high‑wing monoplane powered by a single 400‑hp Liberty V‑12 engine mounted in a streamlined nacelle above the wing, driving a two‑bladed propeller. Its hull featured a watertight, V‑shaped bottom with a reinforced keel, allowing water landings in rough seas, while the wings were braced with wires for added rigidity.

The aircraft’s most famous episode occurred during a 1922 trans‑Pacific attempt when two PN‑9s set out from San Francisco for Hawaii. One aircraft, forced down after engine failure, remained afloat for 52 hours, and the crew famously fashioned a makeshift sail from the wing fabric to drift toward the islands—an episode that highlighted both the aircraft’s durability and the ingenuity of its crew.

Although only a handful of PN‑9s were built and the type was quickly superseded by more powerful amphibians, its daring endurance trial demonstrated the feasibility of long‑range over‑water flight and helped shape future Navy flying‑boat designs, cementing its place in early aviation history.