In 1966, the United States Air Force (USAF) commissioned Cessna to build a military variant of the Skymaster to replace the Cessna O-1 Bird Dog.
Both the civilian and military Skymasters were low-cost twin-engine piston-powered aircraft, with one engine in the nose of the aircraft and a second in the rear of the fuselage. The push-pull configuration provided centerline thrust, allowing simpler operation than the low-wing mounting of most twin-engine light aircraft, and allowed a high wing to be used, providing clear observation below and behind the aircraft.
Modifications made for the military configuration included fore-and-aft seating for a pilot and observer, instead of the six seats of the civilian version; installation of view panels in the doors (for improved ground observation); installation of flame-retardant foam in the wing-mounted fuel tanks (slightly increasing weight, and reducing maximum fuel capacity by 3%); installation of military, rather than civilian, communication and navigation equipment and antennas; removal of propeller spinners; increased gross weight (5,400 lb vs. 4,400 lb in civilian version), with component strengthening as required to support the increase; and removal of interior upholstery.
The first O-2 flew in January 1967, and the plane went into production shortly thereafter. Performance (especially at cruising altitudes) was degraded due to the added antennas and significant weight increase, but was considered sufficient for the anticipated low-level operation.
Length: 29 ft 9 in (9.07 m)
Wingspan: 38 ft 0 in (11.58 m)
Height: 9 ft 4 in (2.84 m)
Wing area: 202.5 sq ft (18.81 m2)
Aspect ratio: 7.13:1
Empty weight: 2,848 lb (1,292 kg)
Max takeoff weight: 5,400 lb (2,449 kg)
Powerplant: 2 × Continental IO-360C/D air-cooled flat-six engines, 210 hp (160 kW) each
Maximum speed: 199 mph (320 km/h, 173 kn) at sea level
Cruise speed: 144 mph (232 km/h, 125 kn) at 10,000 ft (3,000 m)
Range: 1,060 mi (1,710 km, 920 nmi)
Service ceiling: 19,800 ft (6,000 m)
Rate of climb: 1,180 ft/min (6.0 m/s)
Guns: SUU-11/A Minigun Pod
Hardpoints: Four MAU-3A bomb racks
Rockets: LAU-59/A Rocket Launcher, MA-2/A Rocket Launcher
Bombs: SUU-14/A Bomblet Dispenser