Following the success of Luftwaffe Ju 87 Stukas in the German attack on Poland in 1939 and in the offensive in the west in the spring of 1940, the US Army developed a sudden interest in dive bombers. Up to this time, the US Navy and the US Marine Corps had been the only American armed services interested in dive bombers, and had in fact done some pioneering work which had had been one of the inspirations behind the German development of the Stuka.
In pursuit of this new interest, the Army decided to acquire some Navy designs and use them with very little modification as land-based dive bombers. One of these designs was the Curtiss SB2C Helldiver, which the Army acquired under the designation A-25.
The development of the Curtiss SB2C Helldiver began back in 1938, when the US Navy laid down requirements for a new scout/dive bomber aircraft. In August of 1938, an invitation was sent out to the aircraft industry calling for a new dive bomber powered by an air-cooled radial engine. It was to be equipped with folding monoplane wings, retractable landing gear, de-icing equipment, heavy armament, and armor protection for the crew. Six companies submitted proposals, with the Curtiss and Brewster designs showing the greatest promise. They were both powered by the 1700-hp Wright R-2600 air-cooled radial. In January of 1939, Brewster and Curtiss were selected to build prototypes of their designs under the designation XSB2A-1 and XSB2C-1 respectively.
The XSB2C-1 was a monoplane with wings mounted up high enough on the fuselage to permit the installation of an internal bomb bay. The main landing gear retracted inwards, and the wing training edge had split dive flaps. The aircraft was all-metal except for fabric-covered control surfaces. The crew was two--a pilot sitting underneath a rearward-sliding canopy and a gunner sitting underneath a separate forward-sliding canopy. The rear fuselage arrangement was quite similar to that of the earlier SBC biplane dive bomber.
The XSB2C-1 prototype took to the air for the first time on December 8, 1940, Curtiss test pilot Lloyd Childs being at the controls. The prototype crashed on December 21, 1941 after the wings and tail failed while trying to pull out of a dive. Fortunately, the pilot was able to parachute to safety.
On October 1, 1941, the Navy decided to give its combat aircraft names. The SB2C was assigned the name Helldiver, a name long associated with Curtiss naval dive bombers.
Following Pearl Harbor on December 7, 1941, the Helldiver program took on a new urgency. The first four SB2C-1s were assigned special priority so that flight testing could get underway as soon as possible. In the spring, the Navy announced that 3000 additional Helldivers would be ordered from Curtiss. In May, 1000 Helldivers were ordered from Canadian Car and Foundry at Fort William, Ontario. These were assigned the designation SBW, and 450 of them were allocated to the Royal Navy
The first production SB2C-1 was rolled out in June. It was quite similar to the XSB2C-1 with the exception of a slightly taller vertical tail. It flew for the first time on June 30, 1942.
Based on the success of German dive bombing, the US Army became interested in dive bombing as a means of ground attack, and in 1940 procurement of dive bombers was included in the Army Air Corps expansion program. Rather than develop new aircraft from scratch, the Army turned to the Navy's Douglas SBD Dauntless and Curtiss SB2C Helldiver to fill this need. In late 1940, agreement was reached for the Army to get approximately 100 SB2Cs from Curtiss under the recently-signed Navy contract. These planes were referred to as SB2C-1A for contract purposes, but were designated A-25A by the Army. The A-25A was to be standardized to the extent possible with the Navy SB2C-1. An order for 100 A-25As was added to the Navy contract on December 31, 1940.
By the end of 1941, much larger orders for A-25As were being considered, but the Navy felt that all the production capacity of Curtiss Wright's Columbus, Ohio plant would be required to meet its needs. Consequently, the Army Air Materiel Command directed that Curtiss Wright's St Louis plant be turned over to A-25A production. By the spring, 3000 more A-25As were on order.
The A-25A was to be almost identical to the SB2C-1, but with larger main wheels and a larger pneumatic tail wheel. The carrier arrester gear was deleted, but the folding wings were to be retained. In addition, Army radios and additional forward and underside armor plating were fitted. Both the Navy and Army models had larger wheel wells to maintain standardization.
Major subcontractors and suppliers for the Navy production were retained for the A-25A in order to enhance standardization. However, there were problems involved in coordinating engineering and manufacturing between Columbus and St Louis. These snags were not eased very much by the fact that the two plants were divisions of the same company. Enough differences between the A-25A and the SB2C-1 evolved so that the A-25A got its own model number of S84 within the Curtiss organization and its own series of drawings.
The first A-25A took off on its first flight on September 29, 1942, about three months after the initial flight of the first production SB2C-1. It had the folding wings and the wing slats of the SB2C-1. Production and testing preceded rather slowly, and the first ten production examples were not completed until March of 1943. These were destined to be the only A-25As with folding wings. By this time, it was deemed impractical to continue the attempt to maintain standardization between the A-25A and the SB2C-1, since this was now holding up both programs. It was decided to transfer the A-25A program over to an Army contract. This transition added further to delays in the A-25A program, due to problems with inspection authority, government furnished equipment, and coordination with subcontractors.
By the time that A-25A production was underway, the Army had found that it no longer had any need for dive bombers. Army pilots had not been well trained in dive bombing techniques, and their combat experience with the A-24 (Army version of the SBD Dauntless) was less than happy. The A-24 suffered heavy losses from enemy flak, and it was fount that it could not be operated in environments in which less than complete air superiority had been established. Consequently, the A-25As that were delivered to the Army were assigned to various second-line activities such as training and target-towing, and never saw any combat. The Army initially assigned the popular name Shrike to the A-25A, a name which had been associated with Curtiss-built Army attack planes since the A-8/A-10 series back in the early 1930s. However, by the end of 1943, the Army adopted the Navy Helldiver name for the A-25A. By this time the Army's A-25As had been redesignated RA-25A, the R prefix standing for "Restricted", which meant that they were not to be used in combat.
Early in the A-25A program, 150 aircraft had been allocated to the Royal Australian Air Force, with RAAF serials being A69-1 through A69-150. However, the RAAF came to the same conclusion as the USAAF, namely, that it really did not need dive bombers, and only 10 (RAAF serials A69-1 through A69-10) were actually delivered.
410 A-25As (including the 140 which were originally intended for the RAAF) were eventually turned over to the US Marine Corps for use as land-based dive bombers under the designation SB2C-1A. Following a configuration review for the Marine Corps, a program was set up to send the transferred planes through modification centers operated by NAF Roosevelt Field, New York, Consolidated-Vultee, Allentown, Pennsylvania, and Delta Airlines. The SB2C-1As were then issued to Marine Corps VMSB squadrons for operational training. By the end of 1944, all the SB2C-1As had been modified and delivered. Transfer to the Navy's Operational Training Command had begun. They served with VMSB-132, -144, -234, -344, -454, -464, -474, and -484. In the autumn of 1944, the first three became VMTB squadrons and the fourth was disbanded. VMSB-454 became a VMTB squadron in the same period. The last three units were replacement training squadrons based at MCAS El Toro, California. The Navy/Marine Corps SB2C-1As were also destined for a non-combatant role, and both Army and Marine/navy land-based Helldivers were declared surplus at an early date.
Serials of A-25A:
41-18774/18783 Curtiss A-25A-1-CS Shrike 41-18784/18823 Curtiss A-25A-5-CS Shrike 41-18824/18873 Curtiss A-25A-10-CS Shrike 42-79663/79672 Curtiss A-25A-10-CS Shrike 42-79673/79732 Curtiss A-25A-15-CS Shrike 42-79733/79972 Curtiss A-25A-20-CS Shrike 42-79933/80132 Curtiss A-25A-25-CS Shrike 42-80133/80462 Curtiss A-25A-30-CS Shrike
One Wright R-2600-8 air-cooled radial rated at 1700 hp for takeoff and
1450 hp at 12,000 feet.
Performance: Maximum speed 285 mph at 12,400 feet, 269 mph at sea
level. Cruising speed 155 mph. Climb to 10,000 feet in 7.4 minutes.
Service ceiling 24,600 feet. Range 1130 miles at 157 mph with a
1000-pound bombload, 1090 miles with a 2000-pound bombload, 2020 miles
maximum ferry range.
Dimensions: Wingspan 49 feet 8 5/8 inches, length 36 feet 8 inches,
height 14 feet 9 inches, wing area 422 square feet.
Weights: 10,363 pounds empty, 15,075 pounds gross (dive bomber, with
one 1000-pound bomb in bomb bay), 17,162 pounds gross with 2 500-pound
bombs on wing racks, two 1000-pound bombs in bomb bay.
Armament: Four fixed, forward-firing 0.50-inch machine guns in the
wings. One flexible 0.50-inch machine gun operated by gunner in rear
cockpit. A bombload of 2000 pounds could be carried in the internal
bay. A pair of 500-pound bombs could be carried on underwing racks.
Alternatively, the underwing bombs could be replaced by a pair of
58-gallon drop tanks.