The Douglas DB-7/A-20 Boston/Havoc was one of the most popular and effective light bombers of the Second World War. A total of 7478 of these bombers were built, and they served with the USAAF under the designation A-20 and with the RAF under the designation *Boston*. However, it is a little-known fact that there were night fighter versions of this attack plane which served with the RAF under the name *Havoc* and with the USAAF under the designation P-70.
The initial USAAC order for the DB-7 had been for 63 A-20s. They were to be powered by turbosupercharged Wright R-2600-7 radials, and were to have been high-altitude light bombers. However, these engines developed cooling problems and troubles were encountered with the turbosuperchargers. In the event, only the fifteenth aircraft (39-735) was actually fitted with the supercharged R-2600-7 engine. Since it was felt that there was no need for higher power at high altitudes for an aircraft which was meant to perform at its best at low and medium altitudes, all other A-20s were converted to A-20A configuration with 1600 hp Wright R-2600-11 engines without superchargers.
Before the USA entered the Second World War, the USAAC felt that it needed long-range fighters more than it needed attack bombers, and the prototype A-20 (39-735) was adapted for night fighting duties under the designation XP-70. Two unsupercharged 1600 hp Wright R-2600-11s replaced the turbosupercharged R-2600-7s. RAF experience with the modified DB-7 Havoc was used as a guideline. British AI Mk IV radar was mounted in an unglazed nose, with an arrow-like transmitting antenna located in front of the nose, and receiving antennae being located on the fuselage sides and on the port wing. All bomb racks and all defensive armament were removed. The crew was reduced from three to two, the second crewman being a radar operator seated in the rear cockpit. Four 20-mm cannon with 60 rpg were installed in a ventral tub. The success of these modifications led to a USAAC decision on October 15, 1940 to have fifty-nine more of the A-20s on order modified as P-70 night fighters.
Fifty-nine P-70s, originally ordered as A-20s were completed with R-2600-11 engines as night fighters. Serials were 39-736 to 39-740, 39-742 to 39-744, 39-746 and 39-747 and 39-749 to 39-797) They were identical to the XP-70 except for minor equipment changes. Maximum speed was 329 mph at 14,000 feet. An altitude of 12,000 feet could be attained in 8 minutes, service ceiling was 28,250 feet, and combat range was 1060 miles. Weights were 16,031 pounds empty and 20,984 pounds gross. The first P-70 was delivered in April of 1942, and the order was completed in September of that year. The name *Nighthawk* seems to have been given to the P-70, although I don't know if it was official.
P-70A-1 was the designation given to thirty-nine A-20Cs modified as night fighters by the USAAF in 1943. The A-20C was the US equivalent of the British DB-7B. They were powered by two 1600 hp R-2600-23s and were armed with six to eight 0.50-inch machine guns in a ventral tray. Improved radar equipment was installed in the nose. A partial list of serials include 42-33135, 33137, 33141, 33143, 33148, 33152, 33164, 33165, 33170, 33177, 33179, 33221. I would appreciate it if anyone has a more complete list of P-70A-1 serials
P-70A-2 was the designation given to 65 A-20Gs modified as night fighters. The A-20G featured an unglazed nose housing a battery of forward-firing guns. Starting with the A-20G-20-DO production block, the single hand-held machine gun in the dorsal position was replaced by a two-gun Martin turret. The P-70A-2 retained the A-20G's standard battery of forward-firing guns, but all flexible defensive weapons were removed. They were otherwise similar to the P-70A-1. A partial list of serials include 42-54057/54062, 54064/54068, 54103, 54105, 54106, 54108/54110, 54112, 54126/54129, 54131/54142, 54161, 54163/54165, and 54267/54274. Again, I would appreciate hearing from anyone who has a more complete list of P-70A-2 serials.
P-70B-1 was the designation given to a single A-20G-10-DO modified as an experimental night fighter fitted with SCR720 centimetric radar in the nose. Armament consisted of six 0.50-inch machine guns in three blisters on each side of the fuselage.
P-70B-2 was the designation given to 105 A-20Gs and A-20Js modified as night fighter trainers and fitted with SCR720 or SCR729 centimetric radar in the nose. Six to eight 0.50-in machine guns could be carried in a ventral tray, but were not always fitted. Serials were 42-86858, 26892, 86896, 86900/86902, 86904/86911, 43-9682, 42-9727, 9728, 9732, 9727, 9739, 9784/9789, 9992, 10000, 10004, and 21551.
Since the USAAF had no night fighter units when the USA entered World War 2, a night fighter training organization was established at Orlando, Florida. Most of the P-70 Nighthawk aircraft served there with the 481st Night Fighter Operational Training Group to develop tactics and procedures for radar-controlled night interceptions and to train the crews of nineteen night fighter squadrons. Very few of these P-70s ever went overseas, most remaining in the USA to be passed on to the next night fighter units that needed to be trained. Most units trained on the P-70 were reequipped with the Northrop P-61 Black Widow before they transferred overseas.
Only five night fighter squadrons were still equipped with P-70s at the time they were deployed overseas. Four P-70-trained night fighter squadrons were sent with their aircraft to North Africa in 1943 for service with the Twelfth Air Force. However, when they got there, these outfits used Bristol Beaufighter VIF fighters obtained from Britain under Reverse Lend-Lease. The 427th Night Figher Squadron took its P-70s with it when it deployed to Italy, but the squadron exchanged its P-70s for Northrop P-61 Black Widows before it became operational.
The P-70 actually saw some combat action in the Pacific Theatre, although their service there was quite brief. The 6th Night Fighter Squadron began operations in February of 1943 with its P-70s from Henderson Field, Guadalcanal, in an attempt to intercept high-flying Japanese night raiders. It was later supplanted by the 419th Night Fighter Squadron. The 418th and 421st Night Fighter Squadrons flew P-70s operationally in New Guinea for a brief time. The P-70 was not very successful in combat, scoring only two kills during the entire war. The P-70 lacked sufficient performance to intercept Japanese night raiders unless it was extremely fortunate. P-70s were replaced with P-61s just as soon as these aircraft would be made available.
Sources:
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McDonnell Douglas Aircraft Since 1920, Vol 1, Rene J. Francillon,
Naval Institute Press, 1988
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The American Fighter, Enzo Angelucci and Peter Bowers, Orion, 1987.
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American Combat Planes, Ray Wagner, 3rd Edition, Doubleday, 1982.
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War Planes of the Second World War, Fighters, William Green, 1964.
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Early Nightfighter Operations in the Pacific: the P-70 at War, Warren E. Thompson, Combat Aircraft Sept 1999 (Vol 2 No 4), 1999.
- E-mail from Johan Visschedijk on corrections to P-70 serials.
