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Northrop XP-61E (Black Widow) Long-Range Bomber Escort / Heavy Day Fighter Aircraft

 Updated: 12/28/2016; Authored By Staff Writer; Content ¬©

  Northrop XP-61E (Black Widow)  
Picture of Northrop XP-61E (Black Widow) Long-Range Bomber Escort / Heavy Day Fighter Aircraft

Just two conversion models of the Northrop XP-61E were completed from the basic P-61 Black Widow framework during World War 2.

The arrival of the high-flying, long-range Boeing B-29 "Superfortress" strategic bomber in May of 1944 led United States Army officials to consider a long-range fighter escort to protect their expensive, technology-laden investment. Northrop managed to introduce their impressive P-61 "Black Widow" that same year and this marked the first purpose-built American night fighter. Engineers were convinced of the merits of the large fighter as a long-range bomber escort and the company championed the idea to Army officials. Enough interest was had in the endeavor to result in the "XP-61E", a modified version of the successful night fighter.

A pair of P-61B-10 aircraft were set aside for conversion to the long-range, high-altitude bomber escort role. The dorsal turret was removed and the upper fuselage cut down to produce a slimmer, lighter and more aerodynamically refined form. No longer requiring radar (the fighter would be a daytime operator), the nose assembly was cleared of the radar fit and in its place a battery of 4 x 0.50 caliber Browning heavy machine guns installed (the ventral battery of 4 x 20mm cannons seen in the original P-61 fighter was retained). As no radar was carried, the radar operator crewman was expendable which led to a reduction of total crew to two and these personnel were now seated in tandem under a shared bubble-style canopy. More internal fuel stores were added to help increase the aircraft's range - a requirement for the long-range bomber escort role.

The result was a powerful, reasonably fast and well-ranged performer with sleek contours and a promising future. The aircraft held a wingspan of 66 feet with a length of 49.6 feet and height of 13.4 feet. Empty weight was 21,350lb against a laded weight of 40,181lb. Power was from 2 x Pratt & Whitney R-2800-65 radial piston engines of 2,000 horsepower each propelling the aircraft to speeds of 376 miles per hour. Rate-of-climb was 2,500 feet-per-minute with a service ceiling of 30,000 feet and range out to 2,250 miles.

A first-flight was had on January 3rd, 1945. However, in April of that year, the program suffered a considerable setback when the second prototype was lost after an attempted full-power take-off test which resulted in too much damage to save the airframe (the test crew survived after a belly landing).

The changing face of war also meant that the XP-61E was never furthered beyond the pair of flyable prototypes: the B-29 found few challengers in the Pacific and was never fielded over Europe against Germany. Also the age of the jet fighter had arrived which limited the long-term commitment on the part of the Army to prop-driven types like the XP-61E. The long-range escort role was fulfilled, at least for the interim, by the stellar, prop-driven North American F-82 "Twin Mustang".

The design became the last fighter-minded offshoot of the Black Widow series and never saw the light of day as an operational-level product. One of the XP-61E aircraft was reworked by Northrop to become the XF-15 prototype which, in turn, became the F-15 "Reporter" in USAF service - though only thirty-six of the type were acquired. The P-61 itself was retired as quickly as 1954 though not after some 700 were produced.

Northrop XP-61E Facts and Specs (Number Built, Service Entry)

Service Year: 1945
Type: Long-Range Bomber Escort / Heavy Day Fighter Aircraft
National Origin: United States
Manufacturer(s): Northrop - USA
Total Units Built: 2

Structural (Crew, Dimensions, Weights)

Operating Crew (Typical): 2
Overall Length: 49.61 feet (15.12 meters)
Overall Width: 66.01 feet (20.12 meters)
Overall Height: 13.39 feet (4.08 meters)

Weight (Empty): 21,352 lb (9,685 kg)
Weight (MTOW): 40,179 lb (18,225 kg)

Power / Performance (Engine Type, Top Speed)

Engine Type: 2 x Pratt & Whitney R-2800-65 engines developing 2,000 horsepower each.

Top Speed: 327 knots (376 mph; 605 kph)
Maximum Range: 1,955 nautical miles (2,249 miles; 3,620 km)
Service Ceiling: 30,003 feet (9,145 meters; 5.68 miles)
Rate-of-Climb: 2,500 feet-per-minute (762 m/min)

Armament / Mission Payload

4 x 0.50 caliber heavy machine guns in nose installation
4 x 20mm cannons in ventral gun pack

Global Operators (Customers, Users)

United States (cancelled)

Northrop XP-61E (Black Widow) Variants

XP-61E - Base Project Designation; two examples configured from existing P-61B airframes.

Northrop XP-61E (Black Widow) Images