Country of origin:

United States of America / New Zealand

Description:

Single-seat agricultural monoplane

Power Plant:

One 298 kw (400 hp) Lycoming IO-720 eight-cylinder horizontally-opposed air-cooled engine

Specifications:

History:

The Fletcher FU-24 was one of three designs by John Thorp for the Fletcher Aircraft Corporation of El Monte, California, known as the Thorp T15. The FU-24 Utility was adapted for aerial agriculture operations in New Zealand. The prototype (N6505C – later ZK-BDS – c/n 1) was flown for the first time on 14 June 1954, and flew in New Zealand three months later. By 1978 this aircraft had performed 141,000 take-offs and landings, flown 9,480 hrs and spread 100,000 tonnes of fertilizer.

After Type Certification trials the FU-24 entered production, with deliveries beginning in 1955. Kits were supplied and the first aircraft ZK-BHE (c/n 6) first flew on 16 February 1955. This aircraft later entered service with Robertson Air Service Ltd of Hamilton and had a 168 kw (225 hp) Continental O-470-E engine. This was followed by a production run of 61 aircraft, the type becoming very popular in New Zealand, registrations ZK-BHA (c/n 2) to ZK-BIZ (c/n 52) being allotted to production aircraft, 50 being delivered to New Zealand operators, and five being delivered to Australian operators.

Air Parts (NZ) Ltd was formed as a public company in 1957 to import Fletcher FU-24 aircraft and spares from the United States, but, in view of the vital role the aircraft would play in the development of New Zealand farming, it was decided to negotiate the purchase of the world manufacturing rights, these negotiations reaching fruition in 1965, a facility being completed at Hamilton for construction. By 1980 examples had been sold around the world, including 10 to Iraq and 18 to Pakistan.

The first Fletchers were powered by the 168 kw (225 hp) Continental O-470E engine, the first aircraft with the 179 kw (240 hp) engine ZK-BIX (c/n 50) flying in April 1957. In 1962 the Continental IO-470D engine providing 194 kw (260 hp) was installed under a modified cowling, this model becoming known as the FU-24 Mk II.

Production was then transferred to Air Parts (NZ) Ltd, where the Fletcher was built in a range of variants. At this stage the 213 kw (285 hp) Continental IO-520A engine was installed, followed by the 224 kw (300 hp) IO-520F. All surviving aircraft at this time were upgraded to the new engine as units became available. The FU-24A, which was introduced in 1962, was a dual control version for ag-pilot training.

The original American-built Fletcher FU-24 and FU-24A aircraft were powered by a 194 kw (260 hp) Continental IO-470-D engine. Two of these American-built machines were registered in Australia in 1957 as VH-FBC (c/n 60) and VH-FBQ (c/n 62). These operated with Airland at Cootamundra, NSW for a few years, and were exported to New Zealand in November 1965.

The FU-24 in its utility aircraft form could carry a pilot and four passengers, or freight, and the FU-24A could accommodate a maximum of five passengers. In fact, very few passenger-carrying aircraft were built. Some 154 Continental-engined FU-24s were produced with the unique “Jet Cooled” augmentor tubes; and three production aircraft were stretched, fitted with larger hoppers, and had a small increase in wingspan.

A number were exported to Australia, and it was here that the next major step in development was taken, when Australian operator, Pays Aerial Services of Scone, NSW, converted an aircraft to take the 298 kw (400 hp) Lycoming IO-720 eight-cylinder engine. The type became known on the register as the FU-24/A4. Air Parts then commenced to market the type with this engine, which then became known as the FU-24-950, which became the standard production model until 1979, when the FU-24-954 took its place. In addition to new aircraft fitted with this engine, almost all remaining 224 kw (300 hp) aircraft were converted to FU-24-950M standard.

In 1966 stretched FU-24s known as the FU-1060 (PT6A) and the FU-1160 (TPE331) appeared, these being the first all-turbine variants to fly, both being flown during 1967. A number of other developments occurred to the design. These included the Fletcher 1284 fitted with a 496 kw (665 shp) AiResearch TPE-331 turboprop.

The Fletcher FU-24 series was of all-metal construction, treated with plastic paint, etc, to eliminate the corrosive effects of the chemicals carried for top-dressing operations. The manufacturer was then known as Pacific Aerospace Corporation Ltd (PAC), which basically only marketed the Cresco for the agricultural role, although it also built and sold the AESL CT-4 civil and military trainer and the PAC-750XL utility aircraft for freight or parachuting work. In the freight role the FU-24 had a door 91 cm by 91 cm (36 in by 36 in) installed.

More than 300 Fletchers were built and final variant available was the FU-24-954 with the 298 kw (400 hp) Avco Lycoming IO-720-A1A or IO-720-A1B eight-cylinder engine. A total of 82 examples of the FU-24 series has appeared on the New Zealand register and 29 on the Australian register.

In later years a number of standard FU-24-950/954 have been re-engined with Garrett TPE-331-G6 or TPE331-6-252 turbines by Stallion Conversions, the first being VH-GUU (c/n 3002 – ex ZK-EUB) which first flew in 1996, entering service in June that year. A number have been fitted with the Walter M601D, and a V-8 Motorsport engine. Another aircraft has been fitted with a Cresco centre wing and re-engined with an Avco Lycoming LTP-101 turbine, becoming known as the Falcon. Over the years some nineteen different engine models have been installed in the FU-24 airframe.

A Fletcher ZK-EMK (c/n 263) was converted in 2001 to freight configuration and was exported to New Guinea for operation as a freighter to carry coffee beans. Fitted with a turbocharged 261 kw (350 hp) Lycoming TIO-540 engine, it had extra fuel capacity, increasing capacity to 260 litres (57 Imp gals), and operated to strips up to 2,134 m (7,000 ft). It was also fitted with a fuselage cargo pod.

In Malaysia a New Zealand company Super Air operated FU-24s, a  FU-24-950 (ZK-EFN – c/n 217) and an FU-24-954 ZK-EFR (c/n 221) to deliver fertiliser to palm plantations.

The Australian company Super Air operated an FU-24  VH-FMJ (c/n 261) for low-level magnetic survey work in 1997; and Geophysical Technology Ltd formed a partnership with the company to conduct low-level airborne surveys in Australia and North America.

One FU-24 ZK-CYZ (c/n 150) was flown by John Verleun to a customer in Canada, fuel capacity being increased to 1,564 litres (344 Imp gals) for the trip, the longest part of the flight being from Honolulu in Hawaii to San Francisco in California in 27 hrs 15 mins due to strong headwinds.

In 1975 FU-24 ZK-DZJ (c/n 150) was taken to the Paris Air Show, later visiting Britain. An FU-24 (painted as ZK-CTZ) spent many years on a plynth at Hamilton Airport, this being the world’s first turbine-powered agricultural aircraft, having been fitted with a Pratt & Whitney PT-6 engine, having flown 5,325 hours up to the time it was retired in August 1979.  After some deterioration due to weather, it was removed to James Aviation for restoration.

One FU-24 ZK-DZK (c/n 209 – ex ST-ALH, AP-AYR), after time in Pakistan and the Sudan in 1975, was taken in September 1998 to Vanuatu for Sea Air as YJ-NZ23 for use for freight and for emergency ambulance flights. Later in May 2001 it was flown to Australia where it became ZK-UTR.

A number of conversions of FU-24 airframes to turboprop power have occurred, Stallion Conversions fitting the Garrett TPE 331-6-252, the first conversion being VH-EUU (c/n 3002 – ex ZK-EUB) which first flew in 1996, entering service in June that year. A number of FU-24-950s have been fitted with the Walter M601-D turbine.

In 1990 Melbourne-based Aerospace Technologies in Victoria obtained 75.1 per cent of the stock of Pacific Aerospace Corporation (PAC). As stated by Air Parts (NZ) Ltd in the late 1960s, the Fu-24 agricultural and utility aircraft have been “the workhorses of aviation” for many years and will continue to be so into the indefinite future.

In 2006 a new model was produced by Flight Care Ltd of Hawkes Bay Airport, Napier, NZ, this being known as the Crusader and being fitted with a 410 kw (550 shp) Pratt & Whitney PT6A-15AG turboprop. First of this model was ZK-DDX (c/n 160).

Another conversion became known as the Pegasus II, this being fitted with a 448 kw (600 hp) Lycoming LTP-101 turbine.