O3U-2 Corsair

The Vought O3U-2 Corsair was a prototype scout‑observation biplane built for the United States Navy in the early 1930s. Developed from the earlier O2U series, the O3U‑2 featured a more powerful Pratt & Whitney R‑985 Wasp Junior radial engine delivering 450 horsepower, which gave the aircraft a top speed of roughly 165 mph and improved climb performance. Its welded steel‑tube fuselage was covered with fabric, while the wings retained the traditional wooden spar and rib construction, clad in fabric as well. The aircraft incorporated a metal cowling and upgraded radio equipment, and it could be fitted with either a fixed or interchangeable float undercarriage for water operations. Though only a handful were built, the O3U‑2 served as an important testbed for the Navy’s transition toward more powerful, all‑metal monoplanes. The lessons learned from its handling, engine reliability, and amphibious capabilities directly influenced the design of later Vought models such as the famous SBU Corsair series and the iconic F4U “Corsair” fighter. In aviation history, the O3U‑2 represents a pivotal step in the evolution of naval reconnaissance aircraft, bridging the gap between the biplane era and the modern monoplane age.