Northrop XP-61E (Black Widow)

History of the Northrop XP-61E (Black Widow)

The arrival of high-flying long-range Boeing B-29 Superfortress strategic bombers in May 1944 prompted U.S. Army officials to consider escorting long-range fighter jets to protect their expensive technological investments. That same year, Northrop successfully launched the impressive P-61 Black Widow, which represented the first purpose-built American night fighter.

Engineers were convinced of the great fighter's merits as a long-range bomber escort, and the company lobbied Army officials on the idea. The effort to release an improved version of the successful night fighter "XP-61E" generated enough interest.

A pair of P-61B-10 aircraft were reserved for conversion into escort roles for long-range high-altitude bombers. The rear tower has been removed and the upper part of the fuselage has been shortened to create a slimmer, lighter and more aerodynamic profile. Since the radar is no longer needed (the fighter will be the day operator), the nose assembly was removed from the radar mount and 4 x .50 caliber Browning heavy machine gun batteries were installed in its place (the ventral battery was 4 x 20 -mm-gun). What was seen on the original P-61 fighter has been retained).

By not carrying the radar, the radar operator's crew was expendable, reducing the total crew to two, who now sit in tandem under a common bubble canopy. More internal fuel storage was added to increase the aircraft's range - a requirement for the long-range bomber escort role.

The result is a strong, relatively fast and long-range performer with a sleek silhouette and a bright future. The aircraft has a wingspan of 66 feet, a length of 49.6 feet and a height of 13.4 feet. Curb weight is 21,350 lbs, while laden weight is 40,181 lbs. Power comes from 2 Pratt & Whitney R-2800-65 radial piston engines, 2,000 hp each, propelling the aircraft to a speed of 376 mph.

Climb speed is 2,500 feet per minute, service is capped at 30,000 feet, and range is up to 2,250 miles.

The first flight took place on January 3, 1945. However, in April of the same year, the program suffered a major setback as a second prototype was lost after an attempted full-power takeoff attempt resulted in too much damage to save the airframe (testers survived a belly landing).

The changing face of war also meant that the XP-61E never surpassed the pair of airworthy prototypes: the B-29 found few challengers in the Pacific and never saw action against Germany on a European scale. The age of the jet fighter has also arrived, limiting the Army's long-term commitment to propeller-driven fighters like the XP-61E.

The role of long-range escort has been taken, at least temporarily, by the preeminent North American propeller-driven F-82 Twin Mustangs.

The design became the last pugnacious offshoot of the Black Widow series, which never came out as an operational-grade product. One of the XP-61Es was converted by Northrop into an XF-15 prototype, which in turn became an F-15 "reporter" in service with the US Air Force - although only 36 of this type were acquired.

The P-61 itself was retired in 1954, but only after about 700 prototypes had been produced.

Specification

Basic

Production

Roles

Dimensions

Weight

Performance

Performance

Armor

Changes