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The Curtiss F11C Goshawk was the last version of the Hawk biplane fighter to be produced for the US Military, and was similar to the earlier F6C but with a Cyclone engine in place of the Wasp engine used on the older fighter. A version of the F11C with a retractable undercarriage was developed, but it entered service as the Curtiss BF2C.
In the spring of 1932 the US Navy bought two quite similar prototypes from Curtiss. The first was a fairly standard Curtiss Hawk II or Goshawk, which was ordered early in 1932. It was given the BuNo serial number 9213, but the designation XF11C-2. The XF11C-2 was a fairly standard Curtiss Hawk, with single bay staggered tapered wings built around a wooden frame and fabric covered tail surfaces. It was powered by a 600hp Wright SR-1820F Cyclone nine-cylinder single row radial engine and had a two-blade propeller. It used small diameter low pressure wheels and had long single struts for the main wheels. The XF11C-2 was designed to serve as a vertical dive bomber, and could carry a 500lb bomb on the centre line on a bomb rack that swung away from the fuselage to prevent the bomb dropping straight into the propeller (this was originally installed on the XF11C-1 but was soon added to the -2). The XF11C-2 had quite a short active career and was lost in a crash in August 1932.
In April 1932 the Navy ordered a new aircraft, which became the XF11C-1 (BuNo 9217). This retained the general configuration of the Hawk family, with single bay staggered tapered wings, but the wings now used a metal frame in place of the wooden structure on previous aircraft. The ailerons and tail surfaces also had a metal frame and were also metal covered. The aircraft was powered by a 600hp Wright SR-1510-98 two-row radial engine, with a NACA cowling and a three blade propeller. The propeller had 8ft 6in blades, shorter than normal, and so the XF11C-1 was able to use a quite short single strut main undercarriage. This aircraft made its maiden flight in October 1932 and it soon became clear that the engine tended to overheat. The cowling was modified, a longer two blade propeller was installed (requiring the addition of longer legs for the landing gear), and the aircraft effectively became a test machine. In March 1934 it was re-designated as the XBFC-1 and was used by NACA for researching into engine cooling.
The XF11C-2 made its maiden flight in March 1932, before the XF11C-1 had even been ordered. After testing both aircraft the Navy decided to issue an order for twenty-eight F11C-2s. These retained the mixed construction and Cyclone engine of the XF11C-2, and were rather old fashioned aircraft for the early 1930s. They were very similar to the prototype although had larger 30 x 5.00 wheels. Deliveries began in February-March 1933 and went on into 1934.
Early in 1934 the F11C-2s were modified in the field using kits provided by Curtiss. They were given a higher rear turtleback rear deck and a partially sliding canopy which covered the rear half of the open cockpit. In March 1934 the modified aircraft were re-designated as the BFC-2 (bomber-fighter, Curtiss).
The F11C-2 entered service with Navy Squadron VF-1B (the High Hat squadron) on the USS Saratoga in February 1933. In the spring of 1934 they underwent a series of modifications and became the BFC-2 (bomber-fighter class). They remained with the same squadron after the re-designation, while the squadron became VB-2B and later VB-3B.
The fifth production aircraft was used by Curtiss as the basis of the XF11C-3. This saw a manually powered retractable undercarriage added to the basic Hawk fighter. The lower front fuselage was modified to create space for the wheels, which were pulled up using a chain drive. The system had been developed by Grumman, and was used on their FF-1 and F2F-1 fighters. Although it added nearly 400lb to the weight of the aircraft the reduced drag meant that its top speed rose from 205mph to 216mph.
The XF11C-3 was delivered under that designation, but in March 1934 was redesignated as the XBF2C-1 Bomber-fighter. Twenty seven production F11C-3s were ordered, but by the time the first made its maiden flight in September 1934 they had been redesignated as the BF2C-1 (March 1934). The production aircraft used the metal framework of the XF11C-1 prototype and an R-1820-04 Cyclone engine and the combination would cause great vibration problems and limit the service career of the BF2C.
F11C-2/ BFC-2 (as fighter)
Engine: Wright R-1820-78 Cyclone single row radial
Power: 700hp
Crew: 1
Span: 31ft 6in
Length: 25ft 0in
Height: 10ft 7.25in
Empty weight: 3,037lb
Normal loaded weight: 4,120lb
Max speed: 202-205mph
Climb Rate: 2.6 mins to 5,000ft
Range: 560 miles
Armament: Two .3in Browning machine guns
Bomb load: One 500lb or four 112lb bombs
