Curtiss SBC Helldiver

Starting life as a two-seat fighter prototype, designated XF12C-1, ordered by the United States Navy during 1932 and powered by the 625-hp Wright R-1510-92 Whirlwind 14 engine and featuring a parasol wing design it made its maiden flight during 1933. However before the year was out the aircraft was renamed XS4C-1 as it was decided to try the aircraft as a scout but by January 1934 with the aircraft now powered by the Wright R-1820 Cyclone engine and a biplane design it became a scout bomber.

The Helldiver was now to undergo extensive tests, under its new designation of XSBC-1, and it was after a wing failure during a dive test it was decided to order a new prototype with a new designation of XSBC-2 and this would have a biplane wing design. The new Helldiver prototype was powered by the 700-hp Wright R-1510-12 Whirlwind 14 for its maiden flight on the 9th December 1935 before the 825-hp Pratt & Whitney R-1535-82 Twin Wasp Junior engine replaced it during March 1936 and this aircraft was designated the XSBC-3 and it was this design that would be ordered into production on the 19th August 1936 when the United States Navy ordered 83 SBC-3s.

The Curtiss SBC-3 Helldiver had a top speed of 220 mph, range of 405 miles and a service ceiling of 23,800 ft. Armament consisted of a pair of 0.30-in machine-guns and either one 500lb or 1,000lb bomb. The first deliveries of the new type were made on the 17th July 1937 to United States Navy Squadron VS-5 on the USS Yorktown (CV-5).

The final production SBC-3 was renamed the XSBC-4 and would become the prototype of the next variant. The production SBC-4, powered by the Wright R-1820-22 engine, would be an improvement over its predecessor. Although its armament was the same its top speed, 237 mph, range, 590 miles and service ceiling, 27,300ft were all an improvement. An initial order was placed on the 5th February 1938 and the first of 174 SBC-4s were received by the United States Navy during March 1939. When America entered the Second World War (1939 – 1945) in December 1941 the aircraft was obsolete however a number of SBC-4s did equip United States Navy Squadrons VB-8 and VS-8 who were based aboard USS Hornet (CV-8) and they also equipped United States Marine Corps Squadron VMO-151.

With the outbreak of the Second World War the French Government had placed an order for 90 SBC-4 Helldivers during the early months of 1940 for use by the French Navy. To support the French an order was issued by the American Government on the 6th June 1940 that 50 SBC-4s already in service with the United States Navy were to be converted to French standard. This would see the armament change to two French 0.303-in Dove machine-guns.

In total 45 aircraft would be sent to France via Canada, although one aircraft crashed during a transit flight to Canada, but would not arrive before the French had agreed an armistice with Germany. This left five SBC-4s allocated to France left and these were used by the Royal Air Force who renamed the aircraft to Curtiss Cleveland Mk I and used them as ground trainers at RAF Little Rissington and RAF Hendon.

In total 257 Curtiss Helldivers were built.