It was an all-metal, twin-engine, twin-boom design developed during World War II. The first test flight was made on 26 May 1942, with the first production aircraft rolling off the assembly line in October 1943. The last aircraft was retired from government service in 1954.

Although not produced in the large numbers of its contemporaries, the Black Widow was effectively operated as a night-fighter by United States Army Air Forces squadrons in the European Theater, the Pacific Theater, the China Burma India Theater and the Mediterranean Theater during World War II. It replaced earlier British-designed night-fighter aircraft that had been updated to incorporate radar when it became available. After the war, the P-61 served in the United States Air Force as a long-range, all weather, day/night interceptor for Air Defense Command until 1948, and Fifth Air Force until 1950.

On the night of 14 August 1945, a P-61B of the 548th Night Fight Squadron named "Lady in the Dark" was unofficially credited with the last Allied air victory before VJ Day.^[3] The P-61 was also modified to create the F-15 Reporter photo-reconnaissance aircraft for the United States Air Force.^[4]

Specifications (P-61B-20-NO)

Northrop P-61B Black Widow

Data from Jane’s Fighting Aircraft of World War II, and Northrop P-61 Black Widow.

General characteristics

• Crew: 2–3 (pilot, radar operator, optional gunner)
• Length: 49 ft 7 in (15.11 m)
• Wingspan: 66 ft 0 in (20.12 m)
• Height: 14 ft 8 in (4.47 m)
• Wing area: 662.36 ft² (61.53 m²)
• Empty weight: 23,450 lb (10,637 kg)
• Loaded weight: 29,700 lb (13,471 kg)
• Max. takeoff weight: 36,200 lb (16,420 kg)
• Powerplant: 2 × Pratt & Whitney R-2800-65W Double Wasp radial engines, 2,250 hp (1,680 kW) each
• Propellers: four-bladed Curtis Electric propeller, 1 per engine
  • Propeller diameter: 146 in (3.72 m)
• Fuel capacity:
  • Internal: 640 gal (2,423 L) of AN-F-48 100/130-octane rating gasoline
  • External: Up to four 165 gal (625 L) or 310 gal (1,173 L) tanks under the wings

Performance

• Maximum speed: 366 mph (318 kn, 589 km/h) at 20,000 ft (6,095 m)
• Combat range: 610 mi (520 nmi, 982 km)
• Ferry range: 1,900 mi (1,650 nmi, 3,060 km) with four external fuel tanks
• Service ceiling: 33,100 ft (10,600 m)
• Rate of climb: 2,540 ft/min (12.9 m/s)
• Wing loading: 45 lb/ft² (219 kg/m²)
• Power/mass: 0.15 hp/lb (250 W/kg)
• Time to altitude: 12 min to 20,000 ft (6,100 m) (1,667 ft/min)

Armament

• Guns: ** 4 × 20 mm (.79 in) Hispano cannon in ventral fuselage, 200 rounds per gun
  • 4 × .50 in (12.7 mm) Browning machine guns in remotely operated, full-traverse upper turret, 560 rpg
• Bombs: for ground attack, four bombs of up to 1,600 lb (726 kg) each or six 5 in (127 mm) unguided rockets could be carried under the wings. Some aircraft could also carry one 1,000 lb (454 kg) bomb under the fuselage.

Avionics

• SCR-720 (AI Mk.X) search radar
• SCR-695 tail warning radar