On September 13, 1939, the Army ordered eighty examples of a more advanced development of the YP-43 from Republic under the designation P-44. This was basically similar to the P-43 but was provided with the more-powerful Pratt and Whitney R-2180-1 radial engine of 1400 hp. Drawings of the projected P-44 showed an aircraft which looked very much like the P-43 but with a somewhat longer nose and a somewhat heavier armament of six machine guns.
However, combat reports coming out of Europe in the spring of 1940 indicated that even the P-44 Rocket would not be up to the task, and Alexander Kartveli and his design team began to consider an even more advanced project known as the designation XP-47. Kartveli and his team then concentrated all their efforts on the P-47 project, which was to turn out to be a wise decision indeed. However, P-47 development promised to be protracted, the first production aircraft not scheduled to roll off the production lines until late 1942. The Army felt that Republic's Farmingdale production lines needed to be kept busy in the interim. Consequently, the P-44 was ordered into production as a further stop-gap measure.
Republic P-44A Rocket
When the R-2180 engine failed to live up to its promise, Republic selected the Wright R-2600. Unfortunately, as Grumman was to later discover, the R-2600 did not respond well to turbocharging. The P-44A therefore used an unturbocharged R-2600 engine. This made the type ineligible for combat deployment but 80 aircraft were ordered and used as advanced fighter trainers.
Specification of P-44A Rocket
Maximum speed was 375 mph at 10,000 feet, service ceiling was 32,000 feet, and maximum ferry range was 1250 miles. Weights were 6126 pounds empty, 8135 pounds loaded, and 8980 pounds maximum. Wingspan was 36 feet 0 inches, length was 30 feet 6 inches, height was 14 feet 0 inches, and wing area was 223 square feet. Armament was six 0.5 inch machine guns. Provision was made for the carrying of a 41.6 Imp. gall. drop tank, one 200-pound bomb, or six 20-pound bombs.