| XA-21 | |
|---|---|
![]()  | |
| Stearman XA-21 with streamlined cockpit | |
| Role | Ground attack | 
| National origin | United States | 
| Manufacturer | Stearman Aircraft | 
| First flight | 1938 | 
| Status | Prototype | 
| Primary user | United States Army Air Corps | 
| Number built | 1 | 
The Stearman XA-21 (Model X-100) was a competitor in a United States Army Air Corps competition for a twin-engined attack aircraft which (after redesigns) led to the Douglas A-20 Havoc, Martin A-22 Maryland and North American B-25 Mitchell.
Design and development
The X-100, designated XA-21 following purchase by the Army Air Corps, was a twin-engined high-winged monoplane of all-metal construction.[1] Its initial design featured an unusual "stepless cockpit" arrangement, much like those on most German World War II bombers designed during the war years from the He 111P onwards, with a streamlined, well-framed greenhouse canopy enclosing both the pilot and bombardier stations.[2]
Operational history
The XA-21 was first tested with the streamlined cockpit but this configuration was found to restrict the pilot's forward vision, and the aircraft was rebuilt with a conventional (stepped) nose and cockpit structure.[3] Although this change in the cockpit did not significantly affect performance, the XA-21 was not ordered into production.'[4]
The sole XA-21 had serial number 40-191.[5]
Operators
Specifications (XA-21)


Data from Museum of the United States Air Force[4]
General characteristics
- Crew: 3
 - Capacity: 5,560 lb (2,520 kg)
 - Length: 53 ft 1 in (16.18 m)
 - Wingspan: 65 ft 0 in (19.81 m)
 - Height: 14 ft 2 in (4.32 m)
 - Wing area: 607 sq ft (56.39 m2)
 - Empty weight: 12,760 lb (5,789 kg)
 - Gross weight: 18,230 lb (8,269 kg)
 - Powerplant: 2 × Pratt & Whitney R-2180-7 Twin Hornet radial engines, 1,400 hp (1,030 kW) each
 
Performance
- Maximum speed: 223 kn (257 mph, 414 km/h)
 - Cruise speed: 174 kn (200 mph, 322 km/h)
 - Wing loading: 30.0 lb/sq ft (147 kg/m2)
 - Power/mass: 0.15 hp/b (250 W/kg)
 
Armament
- Guns: 
- 4× wing-mounted 0.30 in (7.62 mm) M1919 Browning machine guns
 - 1× nose-mounted 0.30 in machine gun
 - 4× aft-firing 0.30 in machine guns
 
 - Bombs: 2,700 lb (1,200 kg)
 
See also
Related lists
References
Notes
- ↑ "Stearman XA-21 (Stepped Cockpit)." Museum of the United States Air Force. Retrieved: 17 July 2017.
 - ↑ Bowers 1989, p. 273.
 - ↑ "Swift Attack Bombers Race For Jobs In Army Air Corps." Popular Mechanics, June 1939.
 - 1 2 "Stearman XA-21 (Streamlined Cockpit)." Museum of the United States Air Force. Retrieved: 17 July 2017.
 - ↑ Phillips, Edward (2006). Stearman Aircraft: A Detailed History. North Branch, MN: specialtypress. pp. 135–138, 202. ISBN 9781580070874.
 
