With the end of the
war the RAAF was, along with the rest of the military, reduced. However
at the same time the need for modernisation was recognised, and the jet
era had been entered. The RAAF hierarchy decided that a new trainer was
required to replace the very obsolete Tiger Moth fleet, and old technology
Wirraway trainers. The aircraft had to be simple enough for ab initio training,
but complex enough to lead onto the more advanced types entering into service,
specifically the upcoming Vampire jets. Allied to this was the wish of
the government of the day who insisted that any new trainer had to be constructed
with as many Australian made components as possible to strengthen the Australia
aircraft industry. At this time, The British air force was also looking
for a twin seat trainer with similar specifications, and CAC decided to
try for both contracts. Australian specification AC.77 was drawn up in
February 1948 to quantify the various requirements.
The new aircraft required twin seating, with a provision
for a third person, C.S.U., fixed undercarriage, an engine of proven type
with at least 600 hours between overhauls, engine controls to the left
of each pilot, and amongst a long list of other things, good spinning characteristics.
CAC’s submission was the CA-22, which on paper exceeded all the specifications,
and with an eye for future development of their design, CAC also included
provision for retractable undercarriage. The prototype was to be powered
by a Pratt & Whitney Twin Wasp, whilst CAC developed their own radial
for the production versions.
CAC was awarded a prototype contract for two aircraft
in May 1949 and after eighteen months of structural and wind tunnel tests,
the first CA-22 was rolled out on January 26 1951 and flown three weeks
later. Unusually, the testing of the CA-22 was carried out from the beginning
with the involvement of the air force in an attempt to speed up the process.
This did not work as it was soon found that the prototype had handling
problems, most insignificant, but one almost insurmountable; the aeroplane
was so stable that it was very reluctant to spin. The stall was effected
with little or no warning, and the port wing would usually drop very suddenly,
followed by the nose, but recovery was quick and simple a spin would not
develop unless very deliberately and strongly sought. Major airframe and
aerodynamic changes were made, including raising the height of the fin
by 18" (45 cm) and moving it forward by 3’ (98 cm). When this didn't have
the desired effect, the engine also was moved 7" (18 cm) forward. Finally
by mid 1952 the aeroplane reached a performance which satisfied the RAAF
in spins. (This however was still somewhat unusual in that to enter a stable
spin you were required to cross the controls at the point of stall.)
The CAC radial was constructed, a seven cylinder
geared radial of 350 hp named the Cicada, but after flying in a prototype,
it was discontinued in favour of the Pratt & Whitney Twin Wasp. By
the end of 1952 the CA-22 was ready for production, and in early 1953 it
was used by various RAAF stations for evaluation purposes. The British
at some stage decided that they preferred their own design , the Percival
Prentice, (despite the fact that it was not as capable as the CA-22, and
it eventually was replaced by the Provost which co-incidentally bore a
marked similarity to the CA-22) and the Australian government couldn't
decide what to do. Despite the fact that 62 CA-22s were ordered in 1951,
the government vacillated until late 1954 before finally confirming the
order, and allowing production to commence. In that time, the final configuration
had been decided, drawings made, contractors lined up and the aircraft
re-designated CA-25, Winjeel (aboriginal for Little Eagle).
The first production Winjeel was handed over to the
RAAF on August 31st 1955 by Sir Lawrence Wackett, and the last in January
1958. During this time CAC prepared various drawings for conversion of
the Winjeel to other configurations, including a six seat light transport
machine, and an air ambulance. Further drawings encompassed tricycle undercarriage,
twin Turbomeca Aspin II engines, an agricultural Pratt & Whitney turboprop
powered aircraft, and a Rolls Royce Dart turboprop jet trainer. None of
these plans came to fruition however, and the Winjeel remained in general
service until 1969 when the change to "all through" jet training was effected.
In that time the Winjeel came to be a highly regarded training aircraft
capable of being soloed in slightly longer than the Tiger Moth, despite
being markedly more complex. The spinning characteristics caused no problems,
and the serviceability was excellent.
The "all through" scheme turned out to be a bad idea,
and the Winjeel was reinstated as the ab initio trainer after only two
courses had been completed. It continued to serve until 1977 when the last
Winjeel was removed from Point Cook.
During the Vietnam war, Forward Air Controllers (FAC)
were using Cessna Skymasters, and the air force decided in 1969 that it
should train its own FACs, and therefore authorised four Winjeels to be
modified for this role, despite their lack of suitability for the job.
This done, the aircraft were based at 2 OCU Williamtown and formed into
no. 4 flight in 1970. Their job was to train army and air force pilots
in the FAC tasks. Ten years later the flight was absorbed into 77sqn, and
then in 1989 into the newly re-formed 76sqn. There they stayed until they
were replaced in 1994 by the Pilatus PC9.
From its first flight to its final service usage
in 1994 is almost exactly forty years. During that time the Winjeel has
come up with an enviable reputation as a reliable and enjoyable aeroplane
to fly, so much so that it is now a popular machine with "warbird" enthusiasts.
This remarkable service life can be equalled by few aircraft, and in the
Australian military services only one other machine approaches it; the
Iroquois helicopter. Even world-wide there are few machines that can compete,
the only one to spring to mind being the venerable Dakota.
