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circular magazine holding 20 rounds. When the pilot pressed a button on the control wheel, the cannon would automatically fire, reload and continue firing at a rate of one round every 1.2 seconds. To expedite rearming, the front streamlined housing surrounding the weapon was hinged on a set of counterbalanced springs and opened to expose the installation. Designed as a package, the cannon could be removed and replaced with various armament assemblies to deal with combat situations in the field. The cannon worked well during testing, and noise level in the cockpit was deemed acceptable by Army pilots conducting the tests.
To ensure that a pilot could hit the enemy with those hard-hitting shells the airplane was equipped with a Type N-6 reflector sight. Because the cannon was designed and mounted as an extension of the airplane’s longitudinal axis, the pilot simply aimed the XA-38 at the target and fired. The Type N-6 reflector, however, did assist in acquiring a reasonably accurate sight picture. As for the Destroyer’s six 0.50-caliber M-2 machine guns, two were installed on either side of the cannon in the nose section, and the other four were mounted in two remotely-controlled turrets, one above and the other below the fuselage. Each gun had 500 rounds of ammunition available.
The blister-type turrets, built by General Electric, were operated by a gunner who sat in the aft fuselage. He could not control the firing arc of the guns, particularly if both turrets were firing simultaneously. To resolve that problem, an interrupter device would automatically cease firing whenever any part of the airframe came in conflict with the firing arc. The lower turret protected the airplane from below, but the upper turret required a more complex interrupter sequence because of the twin vertical stabilizers, wing tips and propellers. To increase offensive firepower, the pilot could command the gunner to rotate and lock the lower turret in the forward position. According to Beech Aircraft records,
The Model 28 Destroyer would have lived up to its name had it been deployed to the Pacific Theater of War in 1945. The nose-mounted
75 mm cannon could fire up to 20 rounds of various high explosives and the twin 0.50-caliber machine guns would have further multiplied the XA-38’s impressive firepower. (Courtesy Beechcraft Corporation, Special Col- lections and University Archives, Wichita State University Libraries)
the XA-38 was only vulnerable to attack from the rear, but to cope with that possibility the top turret guns could be aimed to fire between the two stabilizers. That capability, coupled with the airplane’s high speed, was thought sufficient to limit any enemy fighter to only one firing pass.
Having a wingspan of 67.08 feet, a length of 51.7 feet and standing 8 feet tall from the ground to the cannon barrel, the Destroyer was not a small airplane. Contrary to “hearsay history” and myth, neither was it based on the Model 18 Twin Beech, but was a totally clean-sheet design that approached medium bombers such as the Martin B-26 Marauder and Douglas A-26 Invader in size and weight. Weighing in empty at 23,300 pounds with a design gross weight of 29,000 pounds, the XA-38 could carry external stores including drop tanks, bombs, depth charges and even torpedoes, as well as a variety of fuel loads that increased maximum allowable weight to an impressive 36,332 pounds.
The landing gear and flaps were powered hydraulically by pumps driven from the accessory section of each engine. If the pumps failed, the gear and flaps could be lowered using a hand pump in the cockpit. A conventional landing gear configuration was selected because it was well suited to operation on crude, rough airfields such as those commonly found on Pacific islands. The main gear featured conventional oleo-pneumatic shock struts and hydraulic brakes, while the slotted-type flaps could be lowered to 45 degrees. A 24-VDC electrical system was powered by dual, engine-driven generators, and an auxiliary unit located in the radio compartment could be controlled by the pilot and was used to start engines and remained active during takeoff and landing.
The fuel system was a marvel of engineering and innovation to suit the mission. Because the Destroyer was designed specifically for a ground attack role, it would always be forced to operate in close proximity to the enemy. All tanks, including engine oil tanks,
26 • KING AIR MAGAZINE
MAY 2024