Curtiss BF2C Goshawk
The Curtiss BF2C Goshawk (Model 67) was a carrier-based biplane fighter-bomber built by the Curtiss Aeroplane and Motor Company, developed from the F11C Goshawk as the first production Hawk with retractable landing gear. The US Navy's twenty-seven BF2C-1s entered service with VB-5B aboard USS Ranger in October 1934, but at cruising power their metal wings vibrated so badly that the aircraft were almost unflyable; attempted fixes failed, withdrawals ran from October 1935 to February 1936, and the aircraft were scrapped in 1937. The export Model 68 Hawk III, with wooden wings, avoided the fault: 137 were supplied to Argentina, China, Thailand and Turkey, Chinese aircraft fought as frontline fighters against Japan in 1937, Thailand licence-built fifty more and kept the type active until 1949, and one Thai Hawk III survives in the Royal Thai Air Force Museum.
Why It Mattered
The BF2C-1 was the first production version of the Navy's Hawk fighter with a retractable undercarriage, a step the carrier service wanted as its biplane fighters reached their limits. In US Navy hands it failed quickly: vibration from its metal wings made it almost unflyable at cruising power, and the type was withdrawn within about a year. Its export twin, the wooden-winged Hawk III, escaped that fault and became a frontline fighter abroad: Chinese Hawk IIIs fought Japan's invasion from August 1937, and Thai aircraft were still active in 1949. They were also the last Curtiss fighters the US Navy accepted for service.
Design Notes
Curtiss developed the type from the F11C-2, deepening the lower forward fuselage to house main wheels that the pilot raised and lowered by a hand-worked chain drive. The retraction system followed the Loening-designed gear of Grumman's XFF-1, and trials credited it with 17 mph more speed than the F11C-2, at some cost in manoeuvrability. The prototype kept the F11C-2's wooden wings and a 700 hp Wright R-1820-80 Cyclone, but the production BF2C-1 switched to metal-framed wings and a 770 hp R-1820-04. Production aircraft also gained a raised rear turtledeck and a semi-enclosed cockpit. Armament was two .30-inch Browning machine guns, and three hardpoints took up to 500 lb of external stores. The export Hawk III kept the retractable gear but reverted to wooden Clark Y wings and used a 770 hp R-1820-F53 Cyclone.
Operational History
The prototype, designated XF11C-3, was delivered to the Navy on 27 May 1933, and an order for twenty-seven production aircraft followed. In March 1934 the Navy redesignated the type BF2C-1 in its new bomber-fighter category, and the first production aircraft flew that September. Deliveries began in October 1934, to bombing squadron VB-5B aboard the carrier USS Ranger. At cruising power, the Cyclone drove the metal wings into vibrations that made the aircraft almost unflyable. Curtiss and the Navy added wing weights and tightened the rigging, and even tested wooden wings on one aircraft, but the Navy decided the remedy was not worth its cost. The BF2C-1s were withdrawn between October 1935 and February 1936 as replacements became available, after roughly a year in service. China operated 102 Hawk IIIs, about a hundred of them licence-built by CAMCO at Jianqiao, and counted the type among its frontline fighter-pursuit aircraft when full-scale fighting with Japan began in August 1937. On 12 October 1937, over Nanjing, the 4th Pursuit Group's commander Gao Zhihang was credited with two victories over Mitsubishi A5M fighters in his Hawk III. By the end of 1937 the better-armed, faster Polikarpov I-15 and I-16 fighters supplied under the Sino-Soviet Treaty had superseded the Hawk III in Chinese frontline service. Thailand ordered twenty-four Hawk IIIs in early 1935 and bought a manufacturing licence, then built fifty more locally during 1937–39. Thai Hawk IIIs fought French forces in the Franco-Thai War and the Japanese invasion of December 1941 before being relegated to training.
Afterlife
After withdrawal, the Navy's aircraft remained grounded until 1937, when they were scrapped. No BF2C-1 survives: Peter M. Bowers, writing in General Aviation News, counted three surviving original Hawks, of which the only one from this design was an export Hawk III in the Royal Thai Air Museum in Bangkok. Wikipedia identifies the Bangkok aircraft as KH-10, and Thai Hawk IIIs were still active in 1949, by then relegated to use as trainers. The Hawk line ended with the Hawk IV, a cleaned-up export version with a fully enclosed cockpit, built as a single demonstrator.