Northrop P-61 Timeline
21 October 1940: Northrop is issued preliminary requirements for a night fighter
from the USAAC.
2 April 1941: A mock-up inspection of the XP-61 is held at Northrop.
17 September 1941: The Army issues a contract for 150 P-61 night fighters.
8 May 1942: Two XP-61 prototypes are completed.
26 May 1942: 1st flight of the XP-61 with test pilot Vance Breese at the controls.
8 July 1943: 1st YP-61 is accepted by the USAAF.
September 1943: Severe tail buffeting occurs when the top turret is moved.
October 1943: 1st P-61A-1 is delivered. The first 37 with the dorsal turret the
the next 200 are delivered without the dorsal turret.
March 1944: A P-61A is delivered to England for evaluation.
17 April 1944: the 423rd Night Fighter Squadron arrives in England attached
to the 9th AF.
May 1944: The 6th Night Fighter Squadron in Hawaii is the 1st P-61 unit in
31 May 1944: 1st combat mission for the P-61 was flown by the 419th over
Green Island in the Solomons. The 419th was the 2nd unit in the Pacific
to receive their Black Widows.
July 1944: 1st P-61B is accepted by the USAAF.
5 July 1944: The P-61 is evaluated against the de Havilland Mosquito. The
results were inconclusive.
6 July 1944: The 6th Night Fighter Squadron CAP over Saipan scores its 1st
victory, a Mitsubishi G4M Type 1 "Betty" to become the 1st P-61 kill.
16 July 1944: A section of the 422nd Night Fighter Squadron is assigned to
chase down V-1 buzz bombs and scores its 1st victory
August 1944: Deliveries begin of the P-61B. The following figures are for the
P-61B-20 with 2 x P&W R-2800-65: 2,250 hp. each.
Max. Speeds: 330 mph./S.L., 352 mph./10,000 ft., 366 mph./20,000 ft.
Range Clean: 410 mls./315 mph./10,000 ft. & 940 mls./223 mph./10,000 ft.
Range Maximum External: 1,900 mls./221 mph./10,000 ft.
Time to Climb: 5,000 ft./2.7 min., 15,000 ft./8.2 min.
Service Ceiling: 33,100 ft.
Weights: 21,282 lb. empty, 29,700 lb. normal combat, 38,000 lb. maximum.
Armament: 4 x 20 mm./200 rpg. + 4 x 0.5 in./560 rpg.
November 1944: 1st flight of the XP-61D.
January 1945: Many P-61s extend their range by removing the top turret and
add a fuselage tank in the cavity.
April 1945: Two XP-61E prototypes are converted from P-61Bs.
July 1945: The first P-61C is accepted by the USAAF. Forty-0ne of this model
were completed by VJ-Day.
Engines: 2 x P&W R-2800-73: 2,100 hp. each at take-off, 2,800 hp. at WEP.
Weight: 24,000 lb. empty, 30,600 lb. normal combat, 40,300 lb. maximum
Max. Speed: 410 mph./20,000 ft., 430 mph./30,000 ft.
Service Ceiling: 41,000 ft.
Climb: 30,000 ft./14.6 minutes.
Range at top speed: 330 mls.
Range with 4,000 lbs. bombs.: 415 mls.
Maximum range: 1,725 mls./195 mph.
15 August 1945: By V-J Day 674 P-61s had been completed by Northrop.
15 of 16 USAAF night fighter squadrons were equipped with the P-61
The 416th NFS of the 12th AF was using the de Havilland Mosquito.
1950: P-61s are being replaced by Jets in the USAF.