Aerospace CT-4A Airtrainer
Both the Airtourer and Airtrainer are visually very similar and, quite unsurprisingly, share a common ancestry. Life for the Airtourer started with a 1953 design by Henry Millicer, Chief Aerodynamicist of the Australian Government Aircraft Factory (GAF), in response to a competition sponsored by the Royal Aero Club (Britain) for a new light aircraft. Millicer's design was announced the winner and on April 10, 1959 the wooden prototype, VH-FMM, powered by a 65-hp Continental engine flew for the first time.
In 1960 the aviation division of Victa Ltd, an Australian company better known for Lawnmower manufacturing, took an interest in the new aircraft and re-engined VH-FMM with a 90-hp Continental engine. While this aircraft was on a demonstration tour of New Zealand design work on an all-metal version, the Airtourer 100 was underway. The prototype, VH-MVA, first flew on December 12, 1961 followed several months later by the first production model, VH-MVC. On July 4, 1962 the Airtourer became the first Australian light aircraft to be granted type approval with further production versions being offered as either the '100' or '115' model. These two versions differed mainly in the choice of engine with the '100' powered by a 100-hp Continental O-200-A and the '115' by a 115-hp Lycoming O-235-C1B.
Meanwhile, Millicer had begun work on a new design, the Victa Aircruiser 210. Although very similar in appearance to the Airtourer, the Aircruiser was a completely new design. Powered by a 210-hp Continental IO-360-D engine, it was intended to be a business commuter or touring aircraft and featured a roomier 4-seat cockpit, conventional cabin enclosure and cockpit door (as opposed to the 2-seat, sliding canopy cockpit of the Airtourer). The prototype made its maiden flight on July 17, 1966 but it was to be the only Aircruiser ever built as shortly after this Victa ceased production, citing a lack of Federal Government support for the Australian aviation industry. By this stage, 167 Airtourers had been built by Victa.
Production moved to New Zealand early in 1967 when Aero Engine Services Ltd (AESL) of Hamilton purchased manufacturing rights to the Airtourer and first option on the Aircruiser. Three partially built Victa Airtourers were completed by AESL before production of the New Zealand built AESL Airtourer began with the first, ZK-COZ (c/n 501), flying on October 12, 1967. A third version of the aircraft was added to the line up at a later date, this being the Airtourer 150 powered by a 150-hp Lycoming O-320 engine. The option on the Aircruiser was taken up in 1969, with the aircraft arriving in New Zealand in December 1969.
It was around this time that AESL re-designated the model numbers and product line with the Airtourer 100 becoming the T1 before being dropped from production (although one was later remanufactured from Victa c/n 50 to AESL c/n 556) and the 115 became the T2. The 130hp Continental powered T3 was basically a field modification with only one produced from new, the 150 became the T4 and the T5 was a 150 fitted with a constant speed propeller. Finally came the 150hp Lycoming powered T6/24 that featured a 24-volt electrical system as opposed to the earlier 12-volt system. The last examples of the T6 were fitted with a 160hp engine.
Following evaluation flying of the prototype Airtourer 150 at Wigram in 1968, the Royal New Zealand Air Force saw the potential of this locally produced aircraft as a primary trainer. Four T6/24 aircraft were ordered in October 1969 and the entered service in May and June 1970 as NZ1760 to NZ1763. The aircraft were used by the RNZAF until 1993 when they were retired and sold by tender. By 1972 production of the Airtourer was coming to an end with the last 2 examples flying in 1973, in its place a new military trainer called the CT/4 Airtrainer had been developed by AESL.
The CT/4 evolved from the Aircruiser but had a 2-seat cockpit with the instructor and student sitting side by side and an optional third seat in the rear. A jettisonable rearward hinged lifting canopy was installed and a 210-hp Continental IO-360-H engine provided power. The most significant difference over the Aircruiser was that the structure of the CT/4 was redesigned for aerobatic maneuvers of +6G to -3G. The CT/4 prototype first flew on February 23, 1972 and a total of 2 prototypes were built in order to refine the design with the second prototype, c/n 002, the only single control model ever made. These two prototypes were the only AESL Airtainers produced as following this, the company became New Zealand Aerospace Industries Ltd and later, Pacific Aerospace Corporation Ltd. The first production model was the CT/4A with initial deliveries beginning in late1973 to the Royal Thai Air Force. Production of the CT/4A amounted to 61 aircraft before the CT/4B was produced. This model was built in both civil and military versions with improvements to the aircraft structure and an inverted oil system (fitted to the IO-360-HB Engine). The aircraft entered service with the RNZAF in 1976 with the delivery of 13 Military CT/4Bs as replacements for the long serving North American Harvard and were supplemented by a further 6 in 1978. Fourteen of the military version (c/n 064 through c/n 077) were ordered by Rhodesia, however due to political reasons they were never delivered. Instead they were converted to CT/4A standard and delivered to the Royal Australian Air Force in 1981 and 1982 some 6 years after they had been built. In 1991 an RNZAF CT/4B (NZ1940, c/n 088) was loaned to PAC and fitted with a 350-hp Allison 250-B17D turbine engine. This became the prototype CT/4C but never went into production although it still remains an option for future customers.
An RAAF CT/4B (c/n 065) purchased back by PAC became the prototype of the current production model; the CT4/E. Structural refinements were made which included adding 10cm to the overall length of the aircraft and moving the wings back due to the change in centre of gravity brought about by the installation of a 300-hpTextron Lycoming AEIO-540 L1B5 engine and a Hartzell 3-blade variable pitch propeller (instead of the 2-blade propeller found on previous models). It first flew on December 14, 1991 and entered production in 1998 with the RNZAF taking delivery of the first of 13 leased aircraft (NZ1985 - NZ1997) in August of the same year. The 13th RNZAF aircraft was delivered in June 1999 by which time the CT/4B had been phased out of service and traded back to PAC. The ex-RNZAF aircraft were converted to civil CT/4B status for Sale to British Aerospace Systems of New South Wales, Australia.
As of June 2002 total production of the CT/4E had reached 32 (c/n 200 through 231). In addition to the 13 RNZAF examples 16 had been delivered to the Royal Thai Air Force, 1 to a private buyer in Israel and 2 to the Defence Science and Technology Agency Singapore with production continuing. Both the Airtourer and Airtrainer prove to be popular and affordable with private owners, approximately 18 Airtourers (both Victa and AESL) and 7 examples of CT/4 series appearing on the New Zealand civil register at the time of writing (including the first prototype CT/4, c/n 001 as ZK-DGY).
Text © 2002 Stuart Russell.
One 157kW (210hp) Rolls-Royce Continental IO-360-H flat-six
Wingspan: 7.92m (26ft)
Length: 7.06m (23ft 2in)
Max T-O weight: 1,088kg (2,400lb)
Max level speed: 286km/h (178mph)
Range: 1,422km (884miles)