CAC Wackett

The CAC Wackett holds an important place in Australia’s aviation history as the first aircraft designed entirely in-house by the Commonwealth Aircraft Corporation (CAC). Developed just before the outbreak of the Second World War, this two-seat military trainer was created to meet the growing need for a reliable, practical, and locally manufactured aircraft capable of preparing Australian pilots for military service. Named after its designer, Sir Lawrence Wackett, the aircraft represented a significant achievement for Australia’s emerging aviation industry and demonstrated the country’s ability to develop its own military aircraft.

First flown in September 1939, the Wackett was designed as a basic and intermediate trainer for the Royal Australian Air Force (RAAF). Its tandem seating, fixed tailwheel landing gear, relatively simple construction, and conventional flight controls made it suitable for teaching essential flying skills. Although its development was affected by engine availability and manufacturing challenges, the aircraft eventually entered service in 1941 and became an important part of Australia’s wartime pilot-training programme.

Manufactured at CAC’s Fishermans Bend facility in Melbourne, the Wackett was produced in a total of 202 examples, including two prototypes and 200 production aircraft. While it was eventually overshadowed by more advanced trainers and other military aircraft, its contribution extended well beyond its original role. Following the Second World War, surviving aircraft found new applications in civilian aviation, agricultural operations, and overseas military service.

The CAC Wackett was more than a training aircraft. It was a milestone in Australian engineering, an expression of the country’s growing industrial independence, and a lasting example of how a straightforward design could make a meaningful contribution to military aviation.

The History and Development of the CAC Wackett

Lawrence Wackett and Australia’s First Indigenous CAC Design

The development of the Wackett was closely associated with Lawrence Wackett, one of Australia’s most influential aviation engineers. Born in 1896, Wackett developed a strong interest in aviation and engineering before becoming involved in aircraft design and military aviation. His experience included service as a military pilot, aircraft development work, and leadership within Australia’s growing aircraft manufacturing sector.

By the late 1930s, Wackett had become a leading figure at the Commonwealth Aircraft Corporation, an organization established in 1936 to develop Australia’s domestic aircraft manufacturing capabilities. The company initially concentrated on producing aircraft based on overseas designs, including the CAC Wirraway, which was derived from the North American NA-16 family. However, the Wackett project provided an opportunity for CAC to move beyond licensed production and demonstrate its own aircraft-design expertise.

The RAAF required an aircraft suitable for elementary and basic pilot training, particularly one that could introduce student pilots to the low-wing configuration used by more advanced military aircraft. The Wackett was therefore designed to bridge the gap between elementary trainers such as the de Havilland Tiger Moth and advanced aircraft such as the Wirraway.

Development of the CA-2 Prototypes

The Wackett project began in 1938, with construction of the first CA-2 prototype commencing in October of that year. The development process took place while CAC was still establishing its manufacturing facilities, contributing to delays in completing the aircraft. The first prototype, designated A3-1, made its maiden flight on September 19, 1939, although some historical accounts give slightly different dates.

Initially powered by a 140-horsepower de Havilland Gipsy Major engine, the aircraft demonstrated that its original powerplant was insufficient for the desired training performance. The second prototype was subsequently fitted with a more powerful 200-horsepower de Havilland Gipsy Six engine, improving its performance in flight. However, the heavier engine reduced some of the expected benefits during takeoff.

CAC therefore investigated an alternative engine installation and eventually selected the American Warner Super Scarab radial engine. Producing approximately 175 horsepower, it offered a suitable balance of power, weight, and operational practicality. Both prototypes were eventually fitted with Warner engines, providing the basis for the production version.

The production aircraft received the designation CA-6 and incorporated refinements intended to simplify manufacturing and support reliable training operations. The RAAF ordered 200 production examples, and the first aircraft entered service in March 1941.

Design and Engineering of the Wackett Trainer

Airframe Construction and Aerodynamic Configuration

The CAC Wackett was a single-engine, low-wing monoplane featuring a conventional tail assembly and fixed tailwheel landing gear. Its configuration was selected to provide students with experience in the handling characteristics of low-wing aircraft while retaining the straightforward design principles required of a practical training platform.

The fuselage was constructed around a welded chrome-molybdenum steel-tube framework, providing a strong structural foundation while keeping weight within reasonable limits. Much of the fuselage was covered with aircraft fabric, while selected areas used metal covering. This combination of materials offered a useful balance between durability, weight, and ease of repair.

The wings and tail surfaces were predominantly wooden, with plywood covering used on the wing structure. This construction method was well established in aircraft manufacturing and could be supported by the woodworking skills and production techniques available in Australia at the time. The wing design also incorporated electrically operated flaps, allowing student pilots to become familiar with an additional flight-control system.

The fixed landing gear featured oleo shock absorbers to reduce the impact of landing loads. Although the aircraft did not have retractable landing gear, dummy retraction controls were fitted in the cockpit to simulate the procedures associated with more advanced aircraft. This was a particularly useful training feature because it helped prepare students for the operational routines they would encounter later in their careers.

Cockpit Layout and Flight Controls

The Wackett’s cockpit was arranged in a tandem configuration, with the instructor or student occupying the forward or rear seat according to the training requirements. Both positions were equipped with flight controls, allowing instructors to demonstrate manoeuvres and take control when necessary.

The cockpit instruments and control arrangements were designed to provide a familiar environment for pilots progressing to the Wirraway. This approach reduced the learning curve when students moved from the Wackett to more advanced aircraft, as many fundamental cockpit procedures and instrument layouts were similar.

The enclosed cockpit provided protection from the elements and supported training in different weather conditions. Its relatively uncomplicated systems also helped students concentrate on basic flying skills, including takeoff, landing, navigation, coordinated turns, and recovery from unusual flight attitudes.

Engine and Flight Performance

The Warner Super Scarab Radial Engine

The production CAC Wackett was powered by the Warner Super Scarab 165, a seven-cylinder, air-cooled radial engine producing approximately 175 horsepower. This powerplant became a defining feature of the CA-6 and provided the aircraft with the performance needed for its intended training duties.

The engine’s air-cooled design reduced the need for complicated cooling equipment, while its radial configuration offered a compact and practical installation for the aircraft’s nose. It drove a two-bladed propeller, providing the thrust necessary for takeoff, climbing, and general flight operations. The Warner engine was also relatively straightforward to maintain, an important consideration for a military trainer expected to undertake frequent sorties.

The availability of the Warner engine was not without difficulties. Production and supply problems affected the early manufacturing programme, while the availability of suitable propellers also caused delays. These challenges reflected the wider pressures facing Australia’s aviation industry as it expanded production during the early years of the Second World War.

Speed, Range, and Flight Characteristics

The Wackett was designed to deliver predictable handling and dependable performance rather than exceptional speed. With its 175-horsepower engine, the CA-6 could reach a maximum speed of approximately 115 mph (185 km/h), while its reported range was around 425 miles (684 km). The aircraft had a service ceiling of approximately 16,000 feet (4,877 metres), giving it sufficient operating flexibility for its intended training missions.

Its handling qualities were considered suitable for a basic trainer. Flight testing indicated that the aircraft was stable both statically and dynamically, with light and effective ailerons, good stall characteristics, and relatively straightforward recovery from an inadvertent spin. These qualities were particularly important for a training aircraft, as student pilots needed an aircraft that could help them develop sound flying techniques while remaining manageable during mistakes and unexpected situations.

The Wackett was not especially powerful by the standards of later military trainers, but its combination of predictable handling, straightforward systems, and useful cockpit visibility made it a valuable aircraft for teaching fundamental flying skills.

The CAC Wackett During the Second World War

Pilot Training for the RAAF

The Wackett entered RAAF service in March 1941, at a time when Australia was expanding its military aviation capabilities in response to the growing global conflict. Its principal role was to provide elementary and intermediate flight training, preparing student pilots for more advanced aircraft and operational duties.

The aircraft served at various RAAF training establishments, where its tandem seating and dual controls supported a structured training programme. Students learned essential flying techniques, including takeoffs, landings, climbing, descending, turns, navigation, and instrument procedures. The aircraft’s fixed landing gear and conventional flight controls also helped students develop the coordination and discipline required for military flying.

The Wackett’s cockpit was deliberately arranged to resemble that of the Wirraway in important respects. This meant that students could become familiar with procedures and controls they would encounter during their next stage of training. Such continuity was valuable in a period when the RAAF needed to prepare large numbers of pilots efficiently.

Although the Wackett was not designed for combat, its contribution to the war effort was substantial. By helping produce trained aircrew, it supported the operational strength of the RAAF during a period of considerable strategic pressure.

Production Challenges and Wartime Priorities

The production of the Wackett took place under difficult industrial conditions. Shortages of engines, propellers, and other components occasionally interrupted deliveries, while CAC was simultaneously involved in manufacturing the Wirraway and preparing for other important aircraft programmes.

The growing threat posed by Japan following the outbreak of the Pacific War in December 1941 increased the demand for Australian-built military aircraft. CAC needed to prioritize production programmes that would provide the greatest immediate contribution to Australia’s defence. As a result, the Wackett production run was completed relatively quickly, with the final aircraft delivered to the RAAF on April 22, 1942.

In total, 200 CA-6 production aircraft were built, in addition to the two CA-2 prototypes. While this number was modest compared with the production totals of some larger military aircraft, the Wackett represented an important achievement for a relatively young Australian aircraft manufacturer.

Variants and Postwar Development

CA-2 and CA-6

The Wackett was manufactured in two principal designations. The CA-2 referred to the two prototypes used to evaluate the original airframe and alternative engine installations. These aircraft initially flew with Gipsy engines before being modified to use Warner radial engines.

The CA-6 was the production version supplied to the RAAF. It incorporated the design refinements developed during prototype testing and was equipped with the Warner Super Scarab engine. The production aircraft became the mainstay of the Wackett fleet and served as an important component of Australia’s military training system.

Overseas Military and Civilian Service

Following the Second World War, the RAAF began replacing its wartime trainers with newer aircraft. A number of surviving Wacketts were sold or transferred to civilian operators, while 30 examples were supplied to the Netherlands East Indies Army Air Force, known as the ML-KNIL. These aircraft became the first Australian-designed aircraft to enter service with a foreign military.

Some of the aircraft supplied to the Netherlands East Indies later passed into Indonesian service, extending the Wackett’s operational history into the postwar period. This overseas use demonstrated the practicality of the aircraft and gave it a place in the early development of regional military aviation.

In Australia, surplus Wacketts also found applications in agricultural aviation. Several aircraft were converted for crop spraying and related activities, while further developments eventually contributed to aircraft such as the Kingsford Smith Cropmaster and the Yeoman Cropmaster. These conversions demonstrated the versatility of the original design and allowed some airframes to continue operating long after their military training careers had ended.

The Legacy of the CAC Wackett

A Milestone in Australian Aircraft Manufacturing

The CAC Wackett occupies a particularly important position in Australia’s industrial and aviation history because it was the first aircraft designed in-house by the Commonwealth Aircraft Corporation. Its development demonstrated that Australian engineers could design, test, manufacture, and support an indigenous military aircraft, rather than relying exclusively on imported designs.

The experience gained from the Wackett programme contributed to CAC’s growing engineering expertise and manufacturing capabilities. The company went on to produce several notable aircraft, including the Boomerang fighter, the Woomera attack aircraft, and the Winjeel trainer. Although these later aircraft involved larger engineering teams and increasingly sophisticated technology, the Wackett helped establish the foundations of CAC’s design culture.

Preservation and Historical Significance

Today, surviving Wacketts are preserved in Australian aviation museums and private collections. Restored examples provide an opportunity to appreciate the aircraft’s traditional construction, tandem cockpit, and distinctive radial-engine configuration. They also serve as reminders of the work performed by the engineers, factory employees, instructors, and student pilots who contributed to Australia’s wartime aviation effort.

The aircraft’s historical importance extends beyond its relatively small production total. It represents a period when Australia was developing the technical expertise and industrial infrastructure needed to support its own defence requirements. The Wackett also illustrates the value of training aircraft, which rarely receive the same recognition as frontline fighters and bombers but play an essential role in developing military aviation capabilities.

CAC Wackett Technical Specifications

The following table summarizes the principal technical specifications of the production CA-6 Wackett Trainer. Figures are representative published values and may differ slightly between sources and individual aircraft.

Specifications are based on published CA-6 aircraft descriptions and historical aviation references.

Individual aircraft records should be consulted for precise configuration and operating limitations.

Conclusion: The Aircraft That Launched an Australian Design Tradition

The CAC Wackett was a practical and historically important aircraft that helped establish Australia’s ability to design and manufacture its own military trainers. Developed under the direction of Lawrence Wackett, it combined a straightforward steel-tube fuselage, wooden wings, tandem seating, and a reliable radial engine to produce an aircraft well suited to the demands of military pilot training.

Although its operational career was relatively short compared with some other wartime aircraft, the Wackett made a valuable contribution to the RAAF by preparing pilots for more advanced machines during a period of rapid military expansion. Its later use overseas and conversion to civilian agricultural roles further demonstrated the adaptability of its basic design.

Perhaps the Wackett’s greatest achievement was the example it set for Australian aviation engineering. It proved that domestic aircraft design could move beyond theoretical ambition and become a practical manufacturing reality. The knowledge and experience developed through the programme helped CAC progress toward increasingly sophisticated aircraft in the years that followed.

The CAC Wackett may not have become a famous combat aircraft, but its importance lies in what it made possible. As Australia’s first fully in-house CAC aircraft design and a successful military trainer, it remains a lasting symbol of engineering determination, industrial progress, and the people who helped build Australia’s aviation future.