SB2C Helldiver
Page 1
Helldivers at War
The dive-bomber expected to replace the SBD was the Curtiss design by Raymond Blaylock judged superior to Brewster’s in a December 1938 competition and ordered as the XSB2C-1 on May 15, 1939. Before prototype flight tests began, a production contract for 370 was placed November 19, 1940, and plans called for the first production SB2C-1 to be delivered by December 31, 1941.
First flown on December 18, 1940, at Buffalo by Lloyd Child, the prototype mid-wing monoplane powered by an R-2600-8 inherited the name Helldiver from the earlier Curtiss biplane. Delivered six months before the Brewster, the XSB2C-1 was faster and its short fuselage would better fit carrier elevators. Severe weight and stability problems appeared, and the prototype crashed February 9, 1941, was modified and rebuilt, but then completely destroyed in a December 21 dive test.
Over 800 changes, including a larger tail, longer nose, self-sealing fuel tanks of increased capacity, and addition of 195 pounds of armor, had to be incorporated into production aircraft before flight tests were made. The new Curtiss factory at Columbus, Ohio was also building the SO3C series with a very inexperienced labor force and the first SB2C-l began flight tests six months behind schedule, on June 30, 1942. Contracts to build 3,865 had been made June 4.
A 1,700 hp Wright R-2600-8 Cyclone turned a spinnered three-bladed Curtiss propeller, and the wings had leading edge slats and folded upward for carrier stowage. The internal bay could hold a 1,000-pound M-59 DAP bomb, or one of the new 1,600-pound Mk 1, or two 1,000-pound M-33 armor-piercing bombs, or a 130-gallon auxiliary tank. Wing racks could accommodate two 325-pound depth charges or 58-gallon drop tanks for special missions.
While one SB2C-1 was tested from November 30, 1942, to January 30, 1943, as a torpedo-bomber, this was not done in actual combat. More trials in May proved that conversion of standard types would require several hours each on the busy carriers, and the flow of TBF-1 Avengers to the fleet made that project unnecessary.
Fifty SB2C-1s were accepted by December 31, and Helldivers were issued in December to two squadrons for the first new Essex class carrier. Too many mechanical faults were found to allow them to begin operations, and the Essex (CV-9) went to sea in March with SBD-4s instead. The next SB2C-1 batch went to the new Yorktown (CV-10) group, but carrier qualification trials went so badly that the aircraft were replaced by SBD-5s when that ship also sailed for the war zone. The Bunker Hill’s VB-17 became the next squadron to try the SB2C-1.
Senator Truman’s Congressional investigation found the program “hopelessly behind schedule” and reported that Curtiss in April 1943, “had not succeeded in producing a single SB2C...useable as a combat airplane” despite expensive self-praise in advertising. In fact, SB2A-1s on hand had been returned to the factory for many modifications. Empty weight increased from the original contract guarantee of 7,868 pounds to 10,114, and the 313-mph top speed guarantee was reduced to 281 mph with military power.
The first 200 SB2C-ls completed by May 1943 had five .50-caliber guns. Instead of the two fixed guns on the prototype’s nose with a telescopic sight, a reflector sight aimed four in the wings. At first a .50-caliber gun on a hydraulic-powered mount protruded from the folding fairing at the rear of the cockpit enclosure, but this had to be replaced by the same twin .30-caliber flexible guns used on the Douglas SBD.
Later Helldivers, beginning with the SB2C-lC, had two 20-mm belt-fed wing guns with 400 rounds. This arrangement of two cannon and twin flexible guns with 2,000 rounds remained on all but those first 200 Helldivers. From May 1943 to March 1944, 778 SB2C-lCs were built at Columbus. These changes did work well enough so that on August 20, 1943, Bunker Hill’s VB-17, replaced its older models with a new set of 36 SB2C-lCs. On November 11, that squadron attacked enemy warships at Rabaul, and it soon appeared that the numerous modifications had succeeded.
The fifth SB2C-1 had become the XSB2C-2 tested March 1943 with twin floats for the Marines and was also the first with the twin flexible guns. A production program was canceled when it was realized the Marines would use land-based aircraft only, and the SB2C-lA from St. Louis was substituted; these were actually 410 surplus Army A-25As with more armor and without folding wings. None actually entered combat, however, but were used for operational training of eight Marine squadrons.
A 1,900 hp R-2600-20 Cyclone, using a four-bladed Curtiss propeller with no spinner, was tested on an XSB2C-3 converted from the 8th SB2C-1, and this engine powered the first production SB2C-3 in December 1943 and the rest of 1,112 delivered by July 1944. Numerous detail refinements were included. By October 1944, every large carrier in the U.S. Fleet had a Helldiver bombing squadron.
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