Friday, December 21, 2012

The XA-38 Grizzly would have been a potent ground-attack component to the Allied cause if it entered production

The XA-38 was a developmental twin-engine heavy fighter produced by the Beech Aircraft firm. By all accounts, she was a stable and fast aircraft comparable to even the single engine speedsters of her day. As promising as her design was, her potential was never realized as the engines slated for the type were reserved for the four-engined Boeing B-29 Superfortress heavy bombers taking precedence. As such, only two XA-38 prototypes were ever built with the project ultimately shelved at the end of the war. Should she have flown in quantity, she might have presented the Empire of Japan with a formidable adversary capable of engaging tanks, vehicles, ships and submarines with equal - and lethal - fervor.


The XA-38 Grizzly would have been a potent ground-attack component to the Allied cause if it entered production.

The United States Army Air Force (USAAF - forerunner to the United States Air Force) entered into a contractual agreement with Beech Aircraft in December of 1942 after considering the company's Beechcraft Model 28 system. The contract called for two initial prototypes to be built as the XA-38 to fulfill a requirement that involved replacing the Douglas A-20 Havocs then in service. This new aircraft would have to exceed in all areas the A-20 excelled at wile making for one truly potent ground attack component vital to eliminating the dug-in Japanese foes throughout the Pacific Theater. The A-20, itself, had its origins in 1939 design and was introduced into operational service in 1941. Its armament and light bombing capabilities allowed the Havoc to make a name for itself in the early years of the war, eventually being fielded by the United States, French, British and Soviet forces. Production of the type finally ended on September 20th, 1944 and a need for its replacement was inevitable. The XA-38 achieved first flight on May 7th, 1944 with Beech test pilot Vern Carstens at the controls, launching from the Beech Aircraft airfield in Wichita, Kansas. It was then flown to Elgin Field in Florida to undergo testing with the US Army.


Design of the XA-38 centered around the large 75mm cannon armament mounted in the nose. The cannon was positioned as such that the barrel protruded from the nose cone assembly of the clean all-metal airframe.

The fuselage was of a conventional design featuring a forward cockpit area and a rear gunner station and fit together as four main sections for ease of maintenance and repairs. Wings were mid-mounted monoplane assemblies (based on the airfoil of the NACA-2300 series) joining the fuselage to each side of the cockpit and designed with a heated leading edge and surfaces to prevent ice from forming at higher altitudes. On the wings were fitted twin Wright R-3350-53 series air-cooled radial piston engines capable of delivering an astounding 2,700 horsepower each while driving three-bladed, constant speed Hamilton Standard propellers. Cooling was provided for through specially-designed circular cowlings and controlled via automatic flaps. The engine nacelles were fitted to the wing leading edges and protruded some, nearly to the extension length of the fuselage nose. The empennage was conventional and featured a horizontal tailplane with two vertical tail fins. The undercarriage was a typical "tail dragger", with two forward single-wheeled landing gears and a single-wheeled tail system - all fully retractable via hydraulics with a backup pneumatic emergency system. Crew accommodations amounted to the pilot and a gunner housed under in separate glazed canopies. The gunner sat in a dorsal position on the empennage.

While the primary armament of the XA-38 was its nose-mounted 75mm cannon (the entire forward nose section was hinged to open upwards for easy access to the cannon), this was further augmented by no fewer than 6 x .50 caliber Browning air-cooled heavy machine guns.

Two were fitted to the lower forward nose section in a forward-firing fixed position while the remaining four were placed in dorsal ad ventral General Electric-brand remote-controlled turrets (two machine guns to a turret). These turrets were traced via periscope sights by the gunner in his rear cabin. Additional external stores would have been conventional drop bombs, a torpedo, smoke bombs, depth charges, chemical tanks and drop tanks. With its accessible hinged nose assembly, the XA-38 was envisioned to fit other adaptable armament systems on-the-fly.

Performance-wise, the XA-38 shined based on reports of the test pilots and servicemen that had the privilege of flying her.

She posted stable flight characteristics but was most notable for her top speed. Her speed was comparable - or better in some cases - to the top-flight single-engine fighters of her day. In one such trial, a chase plane sent up to monitor the XA-38 was found lagging behind the twin-engined beauty. Other impressive performance feats showcased the XA-38's ability to take-off and land in shorter distances at low speed than even her contemporary single-engined brethren. Her powerplants and airframe undoubtedly proved reliable in subsequent evaluations.

A maximum speed of 376 miles-per-hour was recorded along with a service ceiling topping 27,800 feet with twin Wright 2,700 horsepower engines and a crew of two.



Comparatively, the A-20 Havoc sported a top speed of 339 miles-per-hour with a service ceiling of 23,700 feet with twin Wright 1,700 horsepower engines and a crew of three.

The XA-38 would go down as a true American "what-might-have-been" story for a top straight-line speed coupled with a lethal armament package made for one successful aircraft in the Second World War. It is believed that the XA-38 would not have disappointed has it been ordered into production and been available in some number. As fate would have it, the system fell by the wayside as the B-29's took her engines, the need for dedicated attack craft dwindles and the war came to its inevitable close a year later.

Regardless, the XA-38 remains an interesting study. The XA-38 went under the name of "Destroyer" but was more popularly remembered as the "Grizzly". It is known that one of the XA-38 prototypes fell the way of the scrap yard while the whereabouts of the other prototype are unknown.

Specifications for the Beechcraft XA-38 Gizzly / Destroyer (Model 28)

Dimensions:
Length: 51.67ft (15.75m)
Width: 67.06ft (20.44m)
Height: 15.49ft (4.72m)

Performance:
Maximum Speed: 370mph (595kmh; 321kts)
Maximum Range: 1,625miles (2,615km)
Rate-of-Climb: 0ft/min (0m/min)
Service Ceiling: 28,999ft (8,839m; 5.5miles)

Armament Suite:
STANDARD:
1 x 75mm T15E1 cannon in nose
2 x 12.7mm Browning air-cooled heavy machine guns fixed in lower fuselage nose.
2 x 12.7mm Browning air-cooled heavy machine guns in remote-controlled dorsal turret.
2 x 12.7mm Browning air-cooled heavy machine guns in remote-controlled ventral turret.

OPTIONAL (up to 2,000lbs of external stores):
Conventional Drop Bombs
Fuel Droptanks
Smoke Screen Chemical Tanks
Torpedoes
Depth Charges
Structure:
Accommodation: 2
Hardpoints: 2
Empty Weight:22,481lbs (10,197kg)
Maximum Take-Off Weight:36,330lbs (16,479kg)

Powerplant:
Engine(s): 2 x Wright GR-3350-43 Cyclone radial piston engines of 2,300 horsepower each.

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