North American XB-21

The North American XB-21 (North American NA-21) was a prototype bomber aircraft evaluated by the United States Army Air Corps in 1937 but not ordered into production. The North American assigned model number was NA-21.

The aircraft first flew on December 22 1936 and the type was promising enough for the Air Corps to initially place an order for five YB-21 pre-production machines. All these were cancelled, however, when it was found that Douglas' comparable B-18 Bolo was available for around half the price ($63,977 against $122,600). Consequently, no aircraft other than the single initial prototype were built.

Specifications (XB-21)

General characteristics

• Crew: 6-8
• Length: 61 ft 9 in (18.8 m)
• Wingspan: 95 ft 0 in (29.0 m)
• Height: 14 ft 9 in (4.50 m)
• Wing area: 1,120 ft² (104 m²)
• Empty weight: 19,082 lb (8,674 kg)
• Loaded weight: 27,253 lb (12,388 kg)
• Max takeoff weight: 40,000 lb (18,000 kg)
• Powerplant: 2× Pratt & Whitney R-2180-1 radial engines, 1,200 hp (900 kW) each

Performance

• Maximum speed: 220 mph (190 kt, 350 km/h) at 10,000 ft (3,000 m)
• Cruise speed: 190 mph (165 kt, 310 km/h)
• Range: 1,960 mi (1,700 nm, 3,140 km) combat, 3,100 mi (2,700 nm, 5,000 km) ferry
• Service ceiling: 25,000 ft (7,600 m)
• Rate of climb: 1,000 ft/min (5 m/s)
• Wing loading: 24.3 lb/ft² (119 kg/m²)
• Power/mass: 0.088 hp/lb (140 kW/kg)

Armament

• Guns: 5× .303 in (7.70 mm) Browning machine guns
• Bombs: 8,800 lb (4,000 kg)

References and external links

• Encyclopedia of American aircraft

Related content

Comparable aircraft

• B-18 Bolo
• Douglas XB-22
• B-23 Dragon

Designation sequence

• B-18 - XB-19 - Y1B-20 - XB-21 - XB-22 - B-23 - B-24

Related lists

• List of bomber aircraft
• List of military aircraft of the United States