PAC Fletcher - Design and Development

Design and Development

The PAC Fletcher was loosely based on the Fletcher FD-25 Defender, designed by US aeronautical engineer and light aircraft enthusiast John W. Thorp, and originally conceived in 1951 as a STOL light attack aircraft. The prototype Defender was built by Fletcher Aviation in California and first flew in 1953. A few Defenders were later built in Japan.

At the time New Zealand top dressing operators were in the U.S. seeking a replacement for war surplus De Havilland Tiger Moths which formed the backbone of the industry. Thorp and Wendell Fletcher incorporated many elements of the Defender into a new design, the FU-24. A group of New Zealand top dressing operators gathered a hundred options for the design off the drawing board, and founded a company, Air Parts, to assemble the type in New Zealand, while a New Zealand farming company, Cable Price Corporation, funded the construction of two prototypes in the U.S. with the New Zealand Meat Producers Board acting as financial guarantor.

The first prototype Fu 24 flew on 14 June 1954 in the United States, then was disassembled for shipment to New Zealand, together with the (unflown) second prototype. The original prototype had a 225 hp (168 kW) engine and open cockpit. Prior to production commening this design was altered to add an enclosed cockpits and more powerful 260 to 310 hp (230 kW) Continental engines.

The next 70 aircraft were delivered to New Zealand in kit form and assembled at Hamilton airport. From 1961 full production was undertaken locally, by Air Parts, which later became part of AESL and detail improvements and the option of dual controls were added, becoming the mark II.

The Fletcher is a conventional low-wing monoplane with tricycle undercarriage, side-by-side seating in front of the wing and hopper and pronounced dihedral on the outer wing panels. A door aft of the wing's trailing edge on the port side allows access to a cargo compartment. The Fletcher's airframe is constructed entirely of aluminium, heavily treated to prevent corrosion.

After the 257th aircraft the engine was changed to a 400 hp (300 kW) Lycoming O-720 horizontally opposed eight-cylinder engine (over a hundred earlier aircraft were re built and re engined by the factory). Some Fletchers have also flown with V-8 truck engines. In 1967 a PT6 turboprop version was built by James Aviation as ZK-CTZ, a 530 hp (400 kW) Garrett TPE 331-powered version followed in 1968 and a 665 hp (496 kW) Garrett powered version in 1971, both for Robertson Air Service. Several others were converted aftermarket with these or Walter turbines, (including the first prototype, which flew until recently with a Walter).

In the mid 1970s, Pacific Aerospace decided the Fletcher design was reaching the limits of redevelopment and introduced the larger and stronger PAC Cresco. Despite the similar appearance this is a new aircraft, though sharing a few components. For several years production of the two continued side by side, but the type is now effectively out of production, (new Fletchers remain nominally available from the manufacturer, but no new aircraft have been built since a batch of 5 for Syria was completed in 1992).

Although Fletcher was originally the name of the manufacturer in the U.S., and the aircraft was called the FU-24, over time the type has become simply known as the Fletcher. Fletchers have been sold to most parts of the world, although they are rare in Europe and the US. Large government orders came from many developing countries, including Thailand, Syria, Iraq and Sudan.