THE ORIGINS OF THE Commonwealth [Aircraft Corporation CA-25 Winjeel (a title adopted from the Aboriginal language meaning «Young Eagle’) can be traced back to 1948. In that year the RAAF released to Australia’s aeronautical industries, a document that outlined the specifications pertaining to the design and construction of a fixed-wing aircraft for use in the basic training role. This aircraft was planned to replace the long serving DH.82 Tiger Moth and CA-16 Wirraway.
Australia’s Commonwealth Aircraft Corporation (CAC) responded with a design that would provide ab initio student pilots with a basic training platform to furnish them with the skills to cope with the demanding flying regime that is inherent in military aviation. The Winjeel materialised as an indigenous trainer that has through the passage of time, proven to be superior in many respects to the other purpose built training aircraft of contemporary design.
Structurally, the Winjeel is based on a tubular skeletal airframe that is clad with an all-metal stressed skin, the exceptions being the fabric covered control surfaces (ailerons, elevator and rudder). Cockpit layout was rather unique in so far as the seating arrangement accommodated three persons. A student pilot and instructor sat side-by-side and an additional seat was installed immediately behind the instructor’s position.
To comply with the RAAF’s requirement for systems simplicity and ease of maintenance, the Winjeel was fitted out with a non-retractable undercarriage that is tail-dragger configured. Pratt and Whitney’s R-985-AN-2 Wasp Junior radial engine was selected as the power plant as it had already established an enviable reputation for reliability and economical performance. Rated at a modest 450hp, this nine cylinder air-cooled power plant was quite sufficient to satisfy the Winjeel’s tutorial role, providing the trainer with a maximum airspeed of 181 mph (219 km/hr).
DEVELOPMENT Of AN ‘USPINNABLE’ WINJEEL
Full scale development commenced in 1949 following Government approval for the construction of two prototypes destined to provide proof of concept. These were produced under the CAC designation of type CA-22 and allocated RAAF serial numbers A85-618 and ‘364. A85-618 was completed first with a ceremonial roll-out from the Fishermans Bend plant on Australia Day, January 26 1951. After eight days of ground handling trials, CAC’s chief test pilot, John Miles, coaxed ‘618 off the Fishermans Bend runway on February 3, 1951 whereupon an uneventful first flight of 25 minutes duration was completed.
Although preliminary test flights demonstrated the Winjeel’s suitability for the task ahead, CAC’s prototype failed to comply with one of the primary conditions included in the RAAF’s specifications. It had proven to be exceedingly difficult to induce the aircraft into a spin, a failing that required immediate remedial action as that particular aerial manoeuvre is an essential component of the military aviator’s training syllabus. In an attempt to rectify the Winjeel’s reluctance to spin, CAC experimented with a number of modifications to the tail section of the airframe.
The location of the vertical fin was moved forward from its original full aft position, the rudder was reworked to provide an increase in total surface area and a dorsal fairing was fitted. While these modifications produced a significant improvement in the spinning qualities of the CA-22, it was the eventual application of a taller fin that completely resolved the problem, thus producing a fully aerobatic aircraft.
The second prototype A85-364, rolled out on July 20, 1951, incorporated many improvements over ‘618 and in early 1952 it was the recipient of a CAC developed radial engine, the Cicada. This indigenous power plant of 450hp was intended to replace the P & W on the 31st and all subsequent production Winjeels. Unfortunately further development of the Cicada was abandoned in favour of the already proven Pratt and Whitney engine.
THE ‘YOUNG EAGLE’ MATURES
Production of the CA-25 Winjeel commenced in March 1954 with CAC holding a contract for the production of 62 examples. The first emerged from CAC’s plant on February 23, 1955 bearing the RAAF serial A85-401. Deliveries averaged four machines per month with the last of type, A85-462, completed on August 1,1957.
Toward the end of 1955, new Winjeels were beginning to replace the Tiger Moths and Wirraways serving with 1 Basic Flying Training School (BFTS) at Uranquinty in New South Wales. In December 1958, 1 BFTS transferred its base of operations to the recognized birthplace of the RAAF, historic Point Cook in Victoria (see AFM November, page 39). Resting on the shores of Port Phillip Bay, Point Cook became the linchpin for military pilot training courses which dictated that the majority of Winjeels were permanent residents at that base.
One other RAAF training establishment to support Winjeel activities, albeit in smaller numbers, was RAAF Base East Sale, in Victoria, where 1 Central Flying School (CFS) employed six for flying instructor courses. The Winjeel served as the RAAF’s elementary trainer for a full twenty years, during which time all RAAF, AAAvn and RAN trainee pilots cut their teeth on this pugnacious aircraft.
Over that extensive period of continuous operations, the Winjeel earned an enviable reputation for its durability as it absorbed most of the punishment that a student pilot could dish out. Twelve of the machines were written off through primary training related accidents, yet the structural integrity of the airframe was instrumental in minimising loss of life to six personnel.
In July 1972 the Australian Government sealed the fate of the majority of surviving Winjeels when it confirmed an order for 37 CT-4A Airtrainer aircraft. Ironically, the Winjeels successor was another all-Australian design although production rights had been sold to New Zealand Aerospace Industries. Although this decision to procure the CT-4A led to the demise of the Winjeel from its basic trainer role, it has continued to serve the RAAF in a tutorial capacity, only far removed from its original application.
THE VIETNAM LESSON
Reverting back to the mid 1960s, Australia’s commitment of RAAF resources to the Vietnam War was to influence the future utilization of several Winjeels. As Australia’s commitment escalated, RAAF pilots were seconded to units of the United States 7th Air Force so they could gain an insight into USAF operational procedures and combat equipment utilization. One facet of USAF operations to attract considerable RAAF interest was the demanding discipline of Forward Air Control (FAC), an art being practised extensively over the dense jungle and open rice paddies of Vietnam.
Operating such diverse types as Cessna 0-1 Bird Dog, Cessna 0-2 Super Skymaster and the purpose built North American OV-IO Bronco, RAAF personnel gained broad experience in the tactical orchestration of close air support strikes and battlefield resource management. From the experience gained in Vietnam, the RAAF implemented its own FAC training syllabus whereupon a search was initiated to determine a suitable aerial instruction platform.
Owing to budget restrictions a directive was issued that effectively reduced the number of contenders to just two, the Cessna 180E which was then in service with the Australian Army Aviation Regiment (AAAvn), and the RAAF’s own Winjeel. The Winjeel won the selection by default, simply because there were sufficient numbers of the type remaining in service to permit the release of several examples for the FAC training programme.
Even though the Winjeel was to continue on as a trainer in the true sense of the word, it was being impressed into a unique area of training operations which should have been reserved for a purpose built aircraft. While it is fair to say that the machine is not totally unsuited to the task, it is by no means an ideal vehicle from which to conduct actual FAC work as there are performance deficiencies that have the potential to ‘bite’ the unwary, pre-occupied or work engrossed pilot. In particular, the Winjeel provides very little warning of an impending stall that can precipitate an unpredictable wing-drop at the stall which can be quite violent when nap has been selected or the aircraft is under ‘g’ forces. These limitations aside, the aircraft’s utilitarian qualities, rugged construction and all round unobstructed field of vision for the crew are attributes that are of benefit to the crews involved in the FAC training task.
COMMAND THE BATTLEFIELD
Two Winjeels (serial no’s A85-412 and 414) were withdrawn from 1 FTS, arriving at ‘Fighter Town’ RAAF Base Williamtown in August 1968 to become part of 2 (F) Operational Conversion Unit (OCU). FAC training was commenced almost immediately, the momentum of which was increased by the delivery of two additional Winjeels, thus giving a 100% boost to the size of the FAC training inventory. The Winjeel had a nineteen month tenure at occupancy within the infrastructure of 2 OCU, terminating on April 1, 1970 when 4 Forward Air Control Flight was formed. At that time the four FAC configured aircraft on line were serialled A85-407; 413; 436 and 445 unfortunately both of the original FAC machines (A85-412 and 414) had been written off in accidents.
The formation of 4 Flight came about as the Australian military involvement in the Vietnam conflict was beginning to be scaled down toward an eventual total withdrawal. Specifically, it was formed to perpetuate the art of Forward Air Control within the RAAF and expand wherever possible on the original FAC concept. Also, through the nineteen months experience with 2 OCU, it became quite obvious that if the FAC concept was to have any chance of realising it’s full potential, then the personnel operating the Winjeel would need to be provided with a much larger degree of autonomy than would be possible while under the control of the OCU.
REBIRTH OF THE ‘ PANTHER’
4 Forward Air Control Flight remained in existence for eighteen years and three months, whereupon the Flight was incorporated on January 1 1989, as ‘C’ Flight within the newly re-formed 76 Squadron. The ‘Panther’ Squadron was re-formed as a day fighter squadron on Macchi MB-326H equipment to provide lead-in experience on high performance jet aircraft and ground attack techniques for prospective F-111C and F/A-18 drivers. Strategies in the maritime warfare arena are also addressed as fleet support missions for the RAN are a secondary, yet no less important role within the squadron’s operational portfolio. Existing within the structure of 76 Squadron, the unobtrusive ‘C’ Flight comprises four FAC configured Winjeels on strength at any one time, two permanent pilots and seven maintenance personnel from various trade disciplines.
FAC Winjeels are utilized to provide realistic training in Forward Air Control tactics and corelated areas of military operations. Over the years there has been considerable expansion in its role which nowadays encompasses Forward Air Control for RAAF fighter-bomber crews engaging in Close Air Support (CAS) training, and offensive air support of joint Air Force/Army exercises. ‘C’ Flight Winjeels are also used for Air Contact Officer (ACO) courses for the Australian Defence Forces. These personnel are in the main, army officers being trained in the procedures to mark targets and orchestrate air strikes from their position on the ground. Other tasking involves aerial reconnaissance and occasionally, Winjeel crews are called upon to act as Airborne Weapons Range Safety Officers.
Most Winjeel operations are conducted at low level over the many and varied Air Weapon ranges and Military Training Areas that dot Australia’s eastern seaboard, especially those in North Queensland. There are occasions when operational requirements see the aircraft deployed as far away as the Northern Territory and even the odd incursion into Western Australia. However due to the Winjeel’s modest cruising speed, deployments to these far-flung exercise venues are rarely entertained as they can consume upwards of five days travelling in each direction, such is the expanse of the Australian continent.
HIGH VIS GIVES WAY TO WARPAINT
Transition from a sedate basic trainer to a FAC training vehicle involves a small number of simplistic modifications within the crew compartment and to a much lesser degree, the aircraft exterior. Removal of the Winjeel’s unique third seat is necessary to allow the installation of additional radio equipment.
Communications with other aircraft and ground based stations are achieved through normal VHF-AM and UHF-AM sets and a VHF-FM set provides contact with mobile ground forces. A secure voice capability is also included in the radio kit. In early 1991, an advanced navigational aids kit consisting of Automatic Directional Finder (ADF), International Distance Measuring Equipment
(DME) and a Transponder was tested in A85-411. Proven conclusively to reduce pilot workload and fatigue, the full navaid kit has now been installed in each of the FAC configured Winjeels presently on line.
Externally the alterations/additions to the airframe profile are minimal, the most obvious being the assortment of aerials for radio reception and when fitted, a smoke grenade carrying rack. Mounted on the centre line underneath the fuselage mid section, this detachable rack is capable of supporting up to twelve US Mk. 18 smoke generating grenades. The grenades are dispensed individually by a release button on the aircraft’s control column and generally employed as an alternative means of marking a target when artillery is unavailable.
This method of target marking does however, provide an excellent point of reference for fighter-bomber ‘jocks’ engaging in CAS practise. All of the Winjeels selected for FAC work are stripped of their former ‘glory’ as the high visibility basic trainer livery was incompatible with its new operational environment. In its place a tactical camouflage scheme comprising matt dark grey/dark green upper surfaces and mid grey under surfaces is applied.
There have been fourteen Winjeels impressed for FAC operations to date, these being; ‘407/409/410/411/412/413/414/ 415/426/436/438/443/445/458 while ‘427/435/442/453/455 are mothballed at Dubbo in western New South Wales for possible future use. Four FAC configured Winjeels (‘412/414/409/458) have been written off through accidents in the twenty four years of FAC training operations, a very modest rate of attrition when one considers the amount of low level work involved. It is suspected that two, 409 and 414, were lost through the aforementioned lack of stall warning characteristics.
.Contrary to some unfounded reports, there is no planned replacement for the Winjeel as the RAAF’s Forward Air Control trainer at the present time. Rumours abound that the Pilatus
PC-9 is being looked at closely, yet though the type may be undergoing a ‘casual’ assessment, this is certainly no more than part of an ongoing process that is extended to all types within the RAAF inventory. An evaluation has been conducted as to the suitability of the Pilatus PC-6/B1-H2 Turbo-Porter currently serving with the Australian Army, but whereas the report was favourable, the operational future of the Porter is limited as it was withdrawn in late November 1992.
There is quite obviously still plenty of life left in the aging Winjeel, even though the remaining Tife-of-type has yet to be determined. The machines operated by ‘C’ Flight are accruing on average, 250 flying hours per-annum. While this figure could be considered as somewhat modest, it must be remembered that these thirty six year old airframes are being subjected to the torment and high stress related areas of low altitude work for which it was never intended and that some replacement components are becoming increasingly difficult to source as they are no longer manufactured.
The longevity of the CA-25 Winjeel places it in the vintage aircraft category yet, despite its age it is still capable of providing an active and indeed viable contribution to the defence of this country. Its unpretentious role and lack of afterburning performance may preclude it from capturing media headlines, but that does not diminish nor detract from the importance attached to the role that it so capably performs. Hopefully it will celebrate its fortieth anniversary as an active component of the RAAF’s aircraft inventory. What more fitting tribute to those people involved in the design/development and construction of the aircraft, the personnel who have flown and maintained it and continue to do so today and of course, the aircraft itself.