Although the Northrop P-61 Black Widow night-fighter didn’t enter service until mid 1944 it did see combat in both the Pacific and European theatres, and was in action for long enough to prove that it was a successful design.
The size of the aircraft caused some concern amongst new pilots. Northrop dealt with these worried by sending on of their best test pilots, John W Myers, on a tour of P-61 bases, where he would fly a short 'show-off' flight to demonstrate the abilities of the aircraft, often taking up members of the squadron as passengers.
The P-61 made its biggest contribution in the Pacific theatre, where by the end of the war eight squadrons were equipped with the Black Widow. These squadrons operated in scattered detachments, most of which were used to fly combat air patrols over American airfields and bases to protect against the danger from lone Japanese raiders. The squadrons were split between the 5th (418th, 412st and 547th NFS), 7th (6th, 548th and 594th NFS) and 13th (419th and 550th) Air Forces
The 6th and 419ths Squadrons were the first to receive the P-61, on 1 and 3 May 1944. The remaining units received their aircraft over the next seven months, by which time the aircraft was scoring regular victories – the 6th NFS scored its first victory on 20 June, the 421st on 7 July and the 419th on 5 August. By the end of the war the 6th had scored 16 confirmed kills, making it the second highest scoring American night-fighter squadron of the war.
During 1945 aerial targets became increasingly rare, and so many P-61 units turned to long range night-time intruding, carrying out the same mission as the aircraft they had originally been stalking. The 550th NFS even flew a number of direct infantry support missions, helping with the battle on Negros.
Only two squadrons operated the P-61 in the European theatre – the 422nd and 425th Night Fighter Squadrons. It had been hoped that both of these squadrons would be ready by D-Day, but the Black Widow's combat debut was eventually delayed until mid-July, and a shortage of aircraft and spare parts greatly limited the role played by the two squadrons.
The 422nd NFS was formed at Charmy Down near Bath in March 1944. Its first aircraft didn't arrive until 23 May, and training flights didn't start until mid-June. Just as the squadron's air crews were getting used to their new aircraft the 9th Air Force decided to use the Mosquito instead. Only after a fly-off on 5 July, in which the Black Widow out-flew a Mosquito, was the future of the P-61 in Europe secured.
The result of the fly-off has been greeted with a certain amount of scepticism, with many believing that the Mosquito crew were ordered to lose in order to prevent precious aircraft being lost to the USAAF. This is probably not the case, at least as far as speed was concerned – the test was between a Mosquito NF Mk XVII and the P-61A, and the two aircraft had a very similar top speed (especially if the P-61A was a later model with more powerful engines). Only with the arrival of the NF Mk 30 did the RAF get a Mosquito with a better top speed than any P-61, and the Mk 30 didn't make its maiden flight until March 1944. As to manoeuvrability, the P-61 had after all been designed from the start as the fighter, while the Mosquito had originally been seen as a unarmed bomber, using its high speed to escape German pursuit.
Despite the results of the fly-off a good case could still have been made for withdrawing the P-61 from the European theatre in favour of the Mosquito. The two P-61 squadrons were nearly always short of aircraft and spares, dramatically reducing their efficiency during the Battle of the Bulge, but by mid-1944, with two squadrons already forming around the P-61, the time to make that decision had already passed, and if the war had dragged on into the summer of 1945, as many expected, then the P-61 would have made a bigger contribution.
The 422nd finally went operational of 16 July against the V-1 flying bomb, destroying five before moving to France on 25 July. The second squadron, the 425th NFS, received its aircraft on 15 June, and moved to France on 18 August. The two units then moved east with the Allied armies. This brought them up against the Luftwaffe for the first time. In the last few months of 1944 the two squadrons found themselves operating against German intruders, including Fw 190 fighter-bombers, Ju-88s in both bomber and night-fighter versions and the Ju-188.
The two squadrons could have played a major part in the battle of the Bulge, but a lack of aircraft and spare parts meant that they spent much of the battle grounded. During the battle the 422nd only had four airworthy aircraft, and it only flew 35 sorties during January 1945. Despite this the 422nd became the top scoring USAAF night-fighter squadron of the war, scoring 43 victories over manned aircraft and 5 over V-1s. The 425th scored 10 victories over manned aircraft and 4 over V-1s.
By the start of 1945 the Luftwaffe had been defeated, and the night-fighters were free to turn to night intruder missions over German. Train busting became a particular favourite, as they could show up on radar, while the 20mm cannon were a potent weapon.
Four American night-fighter squadrons based in the Mediterranean received the P-61, but only the only one of the four to use the new fighter in combat scored all of its victories operating from Belgium. The 414th Night-Fighter Squadron began to receive its P-61s on 20 December 1944. Soon after this a detachment was rushed north to Belgium, to work alongside the 422nd NFS during the Battle of the Bulge. During this period the detachment claimed five victories with the P-61, the only ones it was to achieve with the aircraft. The detachment remained in Belgium into 1945, flying night intruder missions into Germany
The P-61 was phased out of USAAF service in 1947-8 in favour of the F-82 Twin Mustang, which was itself quickly replaced by newer jet aircraft. In its single year of operations the Black Widow had proved that it was an effective night-fighter. It made a significant contribution to the Allied air campaign in the Pacific, but were never present in enough numbers to do the same in Europe.