Curtiss SB2C Helldiver

https://en.wikipedia.org/wiki/Curtiss_SB2C_Helldiver

The Curtiss SB2C Helldiver is a carrier-based dive bomber aircraft produced for
the United States Navy during World War II. It replaced the Douglas SBD
Dauntless in US Navy service. The SB2C was much faster than the SBD it replaced.
The SB2C Helldiver also saw service with the U.S.Marine Corps (e.g. VMSB-151
AliBaba) flying out of Enjibe Island, Enewetok Atoll on bombing missions.

Crew nicknames for the aircraft included the Big-Tailed Beast or just the
derogatory Beast, Two-Cee, and Son-of-a-Bitch 2nd Class (after its designation
and partly because of its reputation for having difficult handling
characteristics). Neither pilots nor aircraft carrier captains seemed to like
it.

Delays marred its production—by the time the A-25 Shrike variant for the USAAF
was deployed in late 1943, the Army Air Forces no longer had a need for a
thoroughbred dive bomber. Poor handling of the aircraft was another factor that
hampered its service introductions; both the British Royal Navy and the Royal
Australian Air Force cancelled substantial orders.

The Truman Committee investigated Helldiver production and turned in a scathing
report, which eventually led to the beginning of the end for Curtiss. Problems
with the Helldiver were eventually ironed out, and in spite of its early
problems, the aircraft was flown through the last two years of the Pacific War
with a fine combat record.

The Helldiver was developed to replace the Douglas SBD Dauntless. It was a much
larger aircraft, able to operate from the latest aircraft carriers and carry a
considerable array of armament. It featured an internal bomb bay that reduced
drag when carrying heavy ordnance. Saddled with demanding requirements set forth
by both the U.S. Marines and United States Army Air Forces, the manufacturer
incorporated features of a "multi-role" aircraft into the design.

The Model XSB2C-1 prototype initially suffered teething problems connected to
its Wright R-2600 Twin Cyclone engine and three-bladed propeller; further
concerns included structural weaknesses, poor handling, directional instability,
and bad stall characteristics. In 1939, a student took a model of the new
Curtiss XSB2C-1 to the MIT wind tunnel. Professor of Aeronautical Engineering
Otto C. Koppen was quoted as saying, "if they build more than one of these, they
are crazy". He was referring to controllability issues with the small vertical
tail.

The first prototype made its maiden flight on 18 December 1940. It crashed on 8
February 1941 when its engine failed on approach, but Curtiss was asked to
rebuild it. The fuselage was lengthened and a larger tail was fitted, while an
autopilot was fitted to help the poor stability. The revised prototype flew
again on 20 October 1941, but was destroyed when its wing failed during diving
tests on 21 December 1941.

Large-scale production had already been ordered on 29 November 1940, but a large
number of modifications were specified for the production model. Fin and rudder
area were increased, fuel capacity was increased, self-sealing fuel tanks were
added, and the fixed armament was doubled to four 0.50 in (12.7 mm) machine guns
in the wings, compared with the prototype's two cowling guns. The SB2C-1 was
built with larger fuel tanks, improving its range considerably.

The program suffered so many delays that the Grumman TBF Avenger entered service
before the Helldiver, even though the Avenger had begun its development two
years later. Nevertheless, production tempo accelerated with production at
Columbus, Ohio and two Canadian factories: Fairchild Aircraft Ltd. (Canada),
which produced 300 (under the designations XSBF-l, SBF-l, SBF-3, and SBF-4E),
and Canadian Car and Foundry, which built 894 (designated SBW-l, SBW-3, SBW-4,
SBW-4E, and SBW-5), these models being respectively equivalent to their
Curtiss-built counterparts. A total of 7,140 SB2Cs were produced in World War
II.


Role
Dive bomber

National origin
United States

Manufacturer
Curtiss-Wright
Fairchild (Canada) (SBF)
Canadian Car & Foundry (SBW)

Designer
Don R. Berlin

First flight
18 December 1940

Introduction
December 1942

Retired
1959 (Italian Air Force)

Primary users
United States Navy
United States Army Air Forces
French Naval Aviation
Royal Thai Air Force

Produced
1943–1945

Number built
7,140

Developed into
Curtiss XSB3C

The U.S. Navy would not accept the SB2C until 880 modifications to the design
and the changes on the production line had been made, delaying the Curtiss
Helldiver's combat debut until 11 November 1943 with squadron VB-17 on Bunker
Hill, when they attacked the Japanese-held port of Rabaul on the island of New
Britain, north of Papua New Guinea. The first version of the SB2C-1 was kept
stateside for training, its various development problems leading to only 200
being built. The first deployment model was the SB2C-1C. The SB2C-1 could deploy
slats mechanically linked with landing gear actuators, that extended from the
outer third of the wing leading edge to aid lateral control at low speeds. The
early prognosis of the "Beast" was unfavourable; it was strongly disliked by
aircrews due to its size, weight, and reduced range compared to the SBD it
replaced.

In the Battle of the Philippine Sea, 45 Helldivers, most of which had been
deliberately launched from extreme range, were lost when they ran out of fuel
while returning to their carriers.

Among its major faults, the Helldiver was underpowered, had a shorter range than
the SBD, was equipped with an unreliable electrical system, and was often poorly
manufactured. The Curtiss-Electric propeller and the complex hydraulic system
had frequent maintenance problems. One of the faults remaining with the aircraft
through its operational life was poor longitudinal stability, resulting from a
fuselage that was too short due to the necessity of fitting onto aircraft
carrier elevators. The Helldiver's aileron response was also poor and handling
suffered greatly under 90 kn (100 mph; 170 km/h) airspeed; since the speed of
approach to land on a carrier was supposed to be 85 kn (98 mph; 157 km/h), this
proved problematic. The 880 changes demanded by the Navy and modification of the
aircraft to its combat role resulted in a 42% weight increase, explaining much
of the problem.

U.S. Army and Marine Corps service

Built at Curtiss' St. Louis plant, 900 aircraft were ordered by the USAAF under
the designation A-25A Shrike. The first ten aircraft had folding wings, while
the remainder of the production order omitted this unnecessary feature. Many
other changes distinguished the A-25A, including larger main wheels, a pneumatic
tailwheel, ring and bead gunsight, longer exhaust stubs, and other
Army-specified radio equipment. By late 1943, when the A-25A was being
introduced, the USAAF no longer had a role for the dive bomber, as fighter
aircraft such as the Republic P-47 Thunderbolt had shown their ability to carry
out tactical air support missions with great success.

The USAAF transferred 410 Helldivers to the U.S. Marines. The A-25As were
converted to the SB2C-1 standard, but the Marine SB2C-1 variant never saw
combat, being used primarily as trainers. The remaining A-25As were similarly
employed as trainers and target tugs.

Specifications (SB2C-4 Helldiver)

General characteristics
Crew: 2
Length: 36 ft 8 in (11.18 m)
Wingspan: 49 ft 9 in (15.16 m)
Height: 13 ft 2 in (4.01 m)
Wing area: 422 sq ft (39.2 m2)
Airfoil: root: NACA 23017; tip: NACA 23009
Empty weight: 10,547 lb (4,784 kg)
Gross weight: 16,616 lb (7,537 kg)
Powerplant: 1 × Wright R-2600-20 Twin Cyclone 14-cylinder air-cooled radial
piston engine, 1,900 hp (1,400 kW)
Propellers: 4-bladed constant-speed propeller

Performance
Maximum speed: 295 mph (475 km/h, 256 kn) at 16,700 ft (5,100 m)
Cruise speed: 158 mph (254 km/h, 137 kn)
Combat range: 1,165 mi (1,875 km, 1,012 nmi) with 1,000 lb (450 kg) bomb-load
Service ceiling: 29,100 ft (8,900 m)
Rate of climb: 1,800 ft/min (9.1 m/s)

Armament

Guns: **2 × 20 mm (0.787 in) AN/M2 cannon in the wings 2 × 0.30 in (7.6 mm)
M1919 Browning machine guns in the rear cockpit
4 X 0.50 in (13 mm) M2 Browning machine guns, two each in gunpods mounted on
underwing hardpoints (optional)

Rockets: 8 × 5 in (130 mm) high velocity aircraft rockets
Bombs: in internal bay: 2,000 lb (910 kg) of bombs or 1 × Mark 13-2 torpedo
on underwing hardpoints: 500 lb (230 kg) of bombs each



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