The Northrop P-61 "Black Widow
- Length: 49' 7" ; 15.1 m
- Height: 14' 8" ; 4.4 m
- Wingspan: 66' ; 20.1 m
- Gross Weight: 35,853 lb ; 16,260 kg
- Max Weight: 35,855 lb ; 16,260 kg
- No. of Engines: 2
- Powerplant: Pratt & Whitney R-2800-73
- Horsepower (each): 2100
- Range: 1,200 miles ; 1,932 km
- Cruise Speed: 275 mph ; 442 km/h ; 238 kt
- Max Speed: 425 mph ; 684 km/h ; 369 kt
- Ceiling: 46,200 ft ; 14,081 m
The P-61 "Black Widow" was not only the largest, heaviest and most powerful fighter of World War II, but it was the only night fighter designed as such by the American aeronautical industry. It proved to be one of the best aircraft in this role. Although designed in 1940, the P-61 did not go into action until the last year of the war, due to the long and complex preparation required for its radar. Just over 700 were built in three principle versions. Some of these, in photoreconnaissense versions, survived the war and remained in service until 1952.
It was in 1940, when the USAAF strongly felt the need for a valid night fighter with radar apparatus after the reports of a special commission, which was sent to Great Britain to learn about British night interception techniques using the Bristol Blenheim night-fighter. The USAAC realized for the first time that night-fighting was about to become a major element in the air war of World War II, and set about the creation of an American night-fighting capability. In the short term, the best that could be achieved was the Douglas A-20 Havoc (P-70), but for the longer term the USAAC fully appreciated the fact that a type designed strictly for this purpose would be better suited. On October 2, highly secret specifications were issued for an aircraft of this type, and just over a month later, on November 5, John K. Northrop and his chief assistant Walter J. Cerny, who were already working on a design of the kind, submitted a proposal for the project to the military. The project was accepted and launched shortly thereafter. On January 11, 1941, two XP-61 prototypes were ordered, followed by 13 pre-series aircraft YP-61’s on March 10th. On September 1, the first order, for 150 production aircraft was placed.
The first prototype took to the air on May 21, 1942. The "Black Widow", named after the deadly spider found in the American desert, was a large high-wing, two-engine aircraft with tricycle landing gear. It was powered by a pair of Pratt & Whitney R-2800-25 Double Wasp engines rated at 2,000 hp driving 4-blade variable-pitch propellers. In addition, the P-61, was characterized by double tail beams, which lengthened the engine fairings and supported the horizontal and vertical tail fins. The aircraft was fitted with a specific system of control surfaces which notable increased its maneuverability. The radar, based upon British projects and developed by the Massachusetts Institute of Technology, was installed in the nose. The armament consisted of four 20mm cannons fixed in the belly pod and similar number of 12.7mm (.50 cal) machine guns installed in a remote-controlled turret in the rear. After stalking an enemy aircraft the P-61 would open up with all eight guns, pilots said that the enemy aircraft would simply turn into falling chaff.
At first pilots took one look at the massive P-61 and instantly hated it; it was far to big to be a fighter. But then they flew the aircraft and saw it perform. The P-61 was able to stick with the quickest light bombers. One P-61 pilot reports the only "one that got away," in his time in the P-61 was a German Me 262. The pilot stalked the unknown bogey; just when the P-61 crew got to close gun range the Black Widow's radar set off the early-warning in the Me 262. The Me 262 pilot lit his afterburners and raced up and away into the night.
Beginning in August 1944, the first of the second version, the P-61B (450 built) was delivered. In this B version the aircraft’s already powerful armament was increased with the installation of wing supports capable of carrying four 1,602 lb bombs, or supplementary fuel tanks.
The last version, the P-61C, strengthened above all in engine power with the Pratt & Whitney R-2800-73’s which were supercharged and rated at 2,839 hp. Only 41 of the this version were built, out of an order for 517.
In the immediate post-war years another version was delivered. It was intended for photoreconnaissance, and only 36 were built. Designated F-15A "Reporter", the aircraft had a modified fuselage and was characterized by its lack of radar equipment and armament. It had some remarkable qualities. A maximum speed of 440 mph (708 km/h) a 41,101 foot (12,495 m) ceiling, and a range of nearly 4,000 miles. This was the last version of the P-61 to be withdrawn from service sometime in 1952.
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Information from "Flight Journal" Feb 2001, http://www.qsl.net/n3yqh/WWII/p61.htm and http://www.aero-web.org/specs/northrop/p-61c.htm