title: Naval Aircraft Factory XOSN
text: # Naval Aircraft Factory XOSN
  
  The Naval Aircraft Factory XOSN was an American biplane observation floatplane developed by the Naval Aircraft Factory for the United States Navy during the late 1930s.
  
  ## Design and development
  
  In 1936, the Navy asked all interested aircraft manufacturers to submit bids for a new observation-scout aircraft, capable of operating from either water or land, but primarily intended for service on battleships and cruisers for gunnery spotting.
  
  Three companies – Stearman Aircraft, Vought and the Naval Aircraft Factory - submitted aircraft to meet the requirements. The Naval Aircraft Factory design, assigned the designation XOSN-1, was a two-seat biplane of mixed metal and fabric construction, with the pilot and observer seated in tandem in a fully enclosed cockpit. Innovations included automatic leading-edge slats on the upper wing and an I-strut bracing system that eliminated the need for interplane bracing wires. Provisions were made for either float or wheeled landing gear of a conventional taildragger type.
  
  ## Operational history
  
  The XOSN-1 was delivered for official trials in May 1938 and evaluated along with the other entrants. After Vought's monoplane XOS2U-1 was selected for production, the XOSN-1 was assigned to the Naval Academy at Annapolis where it was used as a trainer until mid-1944.
  
  ## Operators
  
  ### United States
  
  * United States Navy
  
  ## Specifications (XOSN-1)
  
  Data from
  
  General characteristics
  
  * Crew: 2 (pilot and observer)
  * Length: 34 ft (10 m)
  * Wingspan: 36 ft (11 m)
  * Height: 13 ft (4.0 m)
  * Wing area: 376 sq ft (34.9 $m^2)$
  * Empty weight: 3,771 lb (1,710 kg)
  * Gross weight: 5,516 lb (2,502 kg)
  * Powerplant: 1 × Pratt & Whitney R-1340 radial engine, 550 hp (410 kW)
  
  Performance
  
  * Maximum speed: 160 mph (260 km/h, 140 kn) at 6,000 feet (1,800 m)
  * Range: 925 mi (1,489 km, 804 nmi)
  * Service ceiling: 14,900 ft (4,500 m)
  
  Armament
  
  * Guns: 1× fixed, forward firing .30 in machine gun; 1× flexibly mounted .30 in machine gun in the rear cockpit
  