CAC Woomera

The CAC Woomera, also known as the CAC CA-4 and CAC CA-11, was an Australian bomber aircraft, which was designed and manufactured by the Commonwealth Aircraft Corporation during World War II. The order for the Woomera was cancelled before it became operational with the Royal Australian Air Force (RAAF).

CAC Woomera
Class Aircraft
Type Bomber
Manufacturer Commonwealth Aircraft Corporation
Origin Australia
Country Name Origin Year
Australia 1941
Country Name Operational Year Retirement Year
Australia View
ManufacturerName Production From Production To Quantity
Commonwealth Aircraft Corporation 2 View

In early 1939, the Australian Government ordered large numbers of Bristol Beaufort bombers, to be built in railway workshops, and in doing so, by-passed the local aircraft company, Commonwealth Aircraft Corporation.

CAC, under Sir Lawrence Wackett, began work on its own design, hoping to out-perform the Beaufort by building a machine that could serve as both a torpedo bomber and dive bomber. To keep down weight, Wackett dispensed with traditional self-sealing fuel tanks and opted to make the wing cavities liquid-tight, and thus serve as fuel storage. The Australian Government was initially uninterested in the CAC design. However, in mid-1940, cut off from the supply of British-made components for the Beaufort program (thanks to a British embargo on the export of aviation products, due to the need to maximise British production during the Battle of Britain), the Australian Government ordered a prototype of the CAC design, even before the Royal Australian Air Force had expressed a view about the machine. This prototype CA-4 took to the air on 19 September 1941. The CA-4 was a low wing, twin-engined, multi-role bomber with a crew of three. It was armed with four nose-mounted .303 calibre machine guns and two remote-controlled twin machine-gun barbettes mounted at the rear of the engine nacelles. It could carry either 500 lb (230 kg) bombs, 250 lb (110 kg) bombs or two torpedoes. It was originally powered by two Pratt & Whitney Twin Wasp R-1830-S3C3-G radials. Unfortunately, the novel fuel tanks never proved reliable, and in January 1943 the CA-4 prototype was completely destroyed in a mid-air explosion, probably due to a fuel leak.

With a re-designed tail and rudder, and an improved nose armament of two 20 mm cannon and two .303 calibre machine guns, the CA-4 became the CA-11 Woomera.

Role light bomber
dive bomber
torpedo bomber
Manufacturer Commonwealth Aircraft Corporation
First flight 19 September 1941
Primary user Royal Australian Air Force
Number built 2

General characteristics

  • Crew: 3 (pilot, bomb aimer/navigator, rear gunner)
  • Length: 39 ft 7 in (12.07 m)
  • Wingspan: 59 ft 2½ in (18.05 m)
  • Height: 18 ft 2 in (5.53 m)
  • Wing area: 440 ft² (40.9 m²)
  • Empty weight: 12,756 lb (5,798 kg)
  • Max. takeoff weight: 22,885 lb (10,402 kg)
  • Powerplant: 2 × Pratt & Whitney R-1830-S3C3-G Twin Wasp 14-cylinder two-row radial engine, 1,200 hp (895 kW) each


  • Maximum speed: 282 mph (454 km/h, 247 knots)
  • Range: 2,225 mi (3,580 km, 1,950 nm) (with external tank and one torpedo)
  • Service ceiling: 23,500 ft (7,165 m)
  • Rate of climb: 2,090 ft/min (10.6 m/s)


  • Guns:
    2 × .303in Browning machine guns in the nose
    2 × 20 mm Hispano MkII cannon in the nose
    4 × .303 Browning machine guns in two rear-firing remotely controlled barbettes
    1 x .303 Vickers K machine gun in a ventral position
  • Bombs:
    4× 250 lb (113 kg) bombs internally in engine nacelle bays
    and 4× 500 lb (224 kg) bombs
    or 2× Mk XII, Mk XV or Mk 13 aerial torpedoes mounted under the fuselage
    or 1× torpedo and 1× 293 imp gal (352 USG) external fuel tank mounted under the fuselage

End notes