Country of origin:

Australia

Description:

Single-seat fighter-bomber

Power Plant:

(CA-12)

One 895 kw (1,200 hp) Pratt & Whitney R-1830-S3C4-G Twin Wasp fourteen-cylinder two-row air-cooled radial engine

Specifications:

Armament:

Two 20 mm Hispano or CAC-manufactured cannon with 120 rounds; four 7.7 mm (0.303 in) Browning machine guns with 4,000 rounds

History:

The suddenness of the Japanese onslaught at the beginning of the war in the Pacific, the speed at which Japanese forces moved, and the possibility of fighter aircraft not being available from overseas sources, led to the decision to design and build a fighter aircraft as soon as possible to meet Australian defence requirements. Lawrence J R Wackett (later Sir) and his team then commenced design of a fighter using many components of the CAC Wirraway trainer, then in production, and the Pratt & Whitney Twin Wasp engine, which was already in production at Lidcombe, NSW, for the Bristol Beaufort bomber, driving a three-blade Hamilton 3T50 constant-speed metal propeller. This was the most powerful engine readily available.

On 21 December 1941 the Australian War Cabinet ordered 105 examples of the Boomerang before a prototype had been built. So urgent was the requirement for the fighter that in fact no prototype as such was built, but every effort was made to complete the first five aircraft as quickly as possible to ensure that flight testing did not reveal any major problems that would have to be rectified in subsequent production aircraft.

On 29 March 1942, sixteen weeks and three days after approval was given to proceed with design work, the first CA-12 Boomerang flew with Kenneth Frewin at the controls. Initial tests revealed the aircraft’s performance was marginally better than expected and, although maximum speed was only 490 km/h (305 mph) at 4,572 m (15,000 ft), the aircraft was extremely manoeuvrable, sturdy, and safe in the hands of an experienced pilot. The most outstanding feature of the aircraft was its rate of climb which, at 884 m/min (2,900 ft/min), was superior to that of the Hurricane I, Spitfire I, Curtiss P-40N and the Focke-Wulf FW-190F-3.

Production of the CA-12 (105 examples – serials A46-1 to A46-105) concluded in June 1943, and production immediately commenced of the CA-13 (95 examples – serials A46-106 to A46-200). These were essentially the same as the CA-12 but with various minor modifications and improvements.

Some investigations were made with a view to increasing the performance of the Boomerang, especially at high altitudes, and an example known as the CA-14 (serial A46-1001) was built fitted with a General Electric Turbo-supercharger installed behind the cockpit, at one stage being fitted with a de Havilland three-blade variable-pitch propeller, and longer more streamlined cowling, being delivered to No 1 Aircraft Performance Unit (APU) in 1944.

Tests of the CA-14 revealed a marked increase in performance but, as the Supermarine Spitfire VIII was by this time entering RAAF service, it was decided not to proceed with production in quantity. This model was developed into the CA-14A but, after testing by No 1 APU at Laverton, VIC, this model did not enter production and was scrapped. This aircraft recorded a max speed of 560 km/h (348 mph) at 8,534 m (28,000 ft).

The final contract for the Boomerang was for the CA-19 (serial numbered A46-201 to A46-249), which did not differ greatly from the CA-13 Boomerang.

In 1944 it was found that the Boomerang was suitable for photo-reconnaissance missions and an F.24 camera was installed in the belly tank. Tests proved successful and all aircraft built from A46-211 onwards had the F.24 camera installed behind the wing rear fairing in the lower fuselage as standard equipment.

Production of the Boomerang continued throughout the war, 25 being delivered in 1942, 146 in 1943, 66 in 1944 and 13 in 1945, the highest number delivered in a month being 22 aircraft in September 1943.

The first RAAF unit equipped with the Boomerang was No 2 Operational Training Unit (OTU) at Mildura, VIC where many problems were experienced, particularly with ground looping when landings were made in cross winds on cambered runways. The first operational Squadron was No 84 based at Horn Island near Cape York Peninsula, QLD to guard against possible attack from the sea. Standing patrols were operated as far as Merauke in New Guinea. First interception of an enemy aircraft was on 16 May 1943 when Boomerangs attacked a flight of three Mitsubishi G3M Bettys with no result. Further units were equipped, including Nos 83 and 85 Squadrons, which were based at Gove in the Northern Territory and Pearce in Western Australia to protect Australia from carrier-borne attacks.

Nos 4 and 5 Squadrons RAAF were equipped and assigned to army co-operation operations in New Guinea, the Solomon Islands and Borneo where they operated with CAC Wirraways attached to the same units. In September 1943 eight Boomerangs and two Wirraways were supporting the Australian 7th and 9th Army Divisions, being employed in supply dropping, tactical reconnaissance and low-altitude strafing missions, a couple being lost to enemy fighters. On one occasion Boomerangs were used to direct an Allied naval bombardment on the east coast of New Guinea.

The Boomerang acquitted itself well in these roles and on many occasions aircraft returned to base with bullet holes from small-arms fire and parts of trees from low-level flying. No 5 Squadron also operated from Bougainville Island finding targets for RNZAF Chance Vought Corsairs, placing smoke bombs on targets. On 14 August 1945 No 4 Squadron took part in the invasion of Borneo by the 1st Tactical Air Force.

For many years only one Boomerang was thought to have survived. This, a CA-12 (serial A46-30), had an interesting career. It was used to represent Sir Charles Kingsford Smith’s Lockheed Altair in a film about his life made in the 1950s. It then spent some time in the grounds of the Australian Air League at Blacktown, NSW until it was obtained by the RAAF, restored and mounted as a gate guardian at RAAF Williamtown, NSW. Eventually, because of its rarity, and the effects of weather, it was moved and placed on display at the RAAF Museum at Point Cook, VIC.

With renewed interest in ‘warbirds’ in later years, many people have become interested in restoring a Boomerang. Many Boomerangs after retirement were broken up at Oakey, QLD, the airframes of these wrecks forming the basis for a number of restoration projects. However, although some fuselages have been located and restoration commenced, there has been a scarcity of suitable wings. In Queensland the owner of a restoration project (Matthew Denning) designed and constructed wings for Boomerang restorations and it is expected in the years to come a small number will fly.

VH-BOM (c/n 1029 – A46-206) was completed for the late Guido Zuccoli and was airworthy, being based at Toowoomba, QLD. It was seen at aviation events until late 2006 when it was transferred to the Museum of Army Flying at Oakey and placed on display. Others flying or under restoration have included A46-122 / VH-MHR (c/n 945) of Matthew Denning which first flew in 2003 and which, in 2006, was transferred to the Temora Aviation Museum where it has been regularly flown. Work on A46-54 (c/n 945) has been proceeding; A46-117 / VH-ZOC (c/n 940) was registered in February 2001 to Arthur Pipe & Steel Australia of Mathoura, NSW; and A46-165 has been under restoration in Sydney.

Another Boomerang was built in the United States. This aircraft registered NX32CS / A46-139 was based on the rear fuselage, centre airframe and modified wings of a North American T-6. It was rebuilt using a number of parts collected by a number of people and was fitted with a Pratt & Whitney R-1820 engine. It was finished in a camouflage scheme and on the port side had the registration A46-139 with a ‘Phooey’ emblem, the latter emblem having been painted on A46-195 with No 4 Squadron at Labuan in North Borneo in 1945. In 2015 it was sold to a European operator and later that year was based at Antwerp in Belgium, being seen on the European air show circuit.

A further Boomerang became VH-XBL (c/n 886) in January 2009 with Boomerang Aviation of Gilberton, SA.

Two Boomerang projects have been held by the Fantasy of Flight Museum in Polk City in Florida, USA for restoration, one of these being on display at the Museum of Flight at Nowra, NSW for some years before being exported.

A replica is being constructed in Western Australia, and A46-147 has been under restoration in Melbourne, VIC for a museum.