To help fulfill a standing U.S. Army attack aircraft requirement, little-known Kaiser-Fleetwings developed a large, single-seat / single-engine conventional monoplane under the "XA-39" designation. The type competed with a collection of other similar offerings but never materialized beyond the mockup stage by which point the Army had moved from its focus on single-engined heavy attackers to twin-engined types and the XA-39 fell to history.
Founded in 1929, Fleetwings was born in Bristol, Pennsylvania and was acquired in 1943 by Kaiser to produce the "Kaiser-Fleetwings" brand label. The brand only saw a few wartime aircraft designs but none ever achieved any sort of notoriety. The company continued operations into the post-war years by which point it was involved in the American space program before closing its doors for good in 1962.
The XA-39 was developed for the ground attack role and this meant a large and rugged, reliable aircraft capable of absorbing punishment from ground-based fire and dealing with the stresses of diving and quick turns. Range was also an important quality as loitering over contested zones was a priority. Typically these aircraft types were required to carry considerable ordnance loads - guns, cannons, rockets, and drop bombs. To power the new design, Kaiser-Fleetwings engineers selected the massive Pratt & Whitney R-2800 series radial piston engine of 2,100 horsepower output and this would be used to drive a three-bladed propeller unit at the nose.
Its overall configuration saw the engine at front with the cockpit immediately aft - though the latter fitted well-forward of midships itself. The pilot was given relatively good views from a slightly-framed canopy. Wings were monoplane appendages and the tail unit was of a standard, single-finned arrangement. The undercarriage utilized a typical "tail dragger" configuration. As with other American warplanes of the period, particularly those expected to fly "low-and-slow", cockpit and engine armoring was to be standard as were self-sealing fuel tanks. Overall dimensions of the XA-39 were a length of 42.8 feet and wingspan of 55.8 feet.
Proposed armament became 2 x 37mm autocannons and up to 4 x 0.50 caliber Heavy Machine Guns (HMGs), all presumably fitted to the wings. An internal weapons bay was to cover the bombing requirement - 6 x 500lb bombs (or equivalent) would envisioned as a standard load.
Engineers estimated the radial engine coupled to the streamlined design would provide the aircraft with a maximum speed of 357 miles per hour when cruising at 16,600 feet. Climb rate would have been 2,040 feet-per-minute and a service ceiling of 27,800 feet being reported. Operational range was out to 1,400 miles.
As previously stated, Army authorities gradually moved away from single-engined attack types and settled on twin-engine platforms for the duration of the war (which ended in 1945). By the end, the single-engined attack type had returned to the forefront of Army plans and classics such as the Douglas "Skyraider" emerged to take the mantle.