| Transavia PL-12 Airtruk |
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To be remembered as the designer of the world’s ugliest aeroplane is perhaps a legacy Italian Luigi Pellarini would not have wanted when he passed away in 2002. His memory remains in the shape of the whacky Transavia PL-12 Airtruk; a twin-boomed single-engine ag-aircraft built around a substantial 400-litre hopper situated behind and below the pilot. Few know that a single African example of his design remains on a Bapsfontein plot some 30 kilometres outside Johannesburg, where it’s tucked under a shade net and trees, as part of a small but fascinating collection of aeroplanes belonging to retired airline pilot, John ‘Fluffy’ McKerchar. Pellarini, it is said, left Italy for Australia in somewhat of a huff, unable to attract financing for his road-driveable aeroplanes, which had become fashionable, if impractical, in the years immediately following World War Two. The designer’s signature project was a PL-2C cabin pusher-propeller monoplane with folding wings and a narrow tricycle undercarriage. The mind boggles at the notion of the slender wheel track providing enough stability on Europe’s narrow and twisting roads for the wing-less aeroplane. Despite the practical barriers to an aeroplane which could be driven on roads, Pellarini managed to build at least one PL-2C in 1946. There were a handful of other designs, most of which were never realised, before Pellarini’s financiers lost interest. The Italian, who boasted that his later PL-5 flying car had flown 250 hours and had been driven over 8,000 kilometres, arrived in Australia as an embittered Italian immigrant, according to historian DG Cameron. His two PL-5s had been left behind, one surviving until the early seventies, until eventually lost in a hangar fire. In Australia Pellarini took up from where he had left off, designing unconventional flying machines. In 1955, encouraged by a commission to design an agricultural aircraft, he applied his fertile mind to producing something truly practical, if unusual. His interpretation was to simply build a metal hopper and attach an engine, biplane wings, boomed tailplane and cockpit. This was Pellarini’s PL-7, which flew for the first time in September 1956. A 400hp Armstrong Siddeley Cheetah-10 engine was hung on the airframe, and surprisingly, it was reported to be easy to fly. Another fire at Bankstown Airport was to claim the sole prototype, which led the Italian to design a further ag-aircraft, the PL-11. The PL-11 was inspired by the sudden availability of some ex-New Zealand air force Harvard components. They were thoughtfully acquired by a Te Kuiti, New Zealand engineer, George ‘Snow’ Bennett, who had spotted the potential for using their engines and other components to build a new aeroplane. Thus the radial engined PL-11 was born, using the Harvard’s R-1340 Wasp engine and various other components that included one of the canopy frames. Both of the two completed Bennett PL-11s were destroyed in accidents, and Pellerini was approached by a new company, Transavia, to improve on the PL-11. Bennett, now out of pocket, joined the new team. Using the PL-11’s weight-saving and corrosion-resistant twin-boom layout, Pellarini’s new PL-12 Airtruk was to prove New Zealand’s first successful commercial aircraft design. Its appearance and clever features appealed to New Zealand’s operators whose curiosity was aroused sufficiently for local topdressing flyers to eventually buy almost 30. A total of 118 of the various models was produced until Transavia closed in 1993. The Airtruk might have been extraordinarily ugly, but it was otherwise a fine aeroplane. Strong, and with good handling qualities, especially in the slow speed regime, it did however have a very noisy cockpit. The frontal area is built using molybdenum tubing bolted to a metal and glass-fibre hopper structure which supported a large rear-fuselage moulding designed to carry a pair of loaders and any field support equipment. In fact it is possible to stand up in the rear cabin, and Transavia even produced a utility version, replacing the hopper area with seating for a further three occupants. The undercarriage legs are interchangeable, as are the ailerons and flaps. Mooney-type rubber shock absorbers gave the PL-12 a bouncy ride on rough surfaces. The hopper was filled by driving a chemical dispenser between the two booms, and filling the 36 cubic/feet tank directly. Like Pellarini’s previous agricultural aeroplanes, the PL-12 Airtruk’s inherent strength relied on a stout hopper, fashioned, unconventionally, from steel. The hopper was attached to a sesquiplane, itself consisting of a D-section steel leading edge and supporting struts that reinforced the undercarriage mountings and carried through the fuselage. Although New Zealand operators used their Airtruks almost exclusively for superphosphate spreading, export aircraft were fitted with a single point fluid filler on the lower fuselage. However, trying to stem liquid leaks in an ag-aircraft designed for solids was an ongoing challenge. Cruising at a modest 100 knots, the PL-12 could easily lift its own weight on the power of its single Continental IO-520 engine. Three aircraft were sold to South African buyers. One was written off, and another badly damaged during spraying operations in Natal. Both aircraft eventually found their way to Australia where they were re-built - but crashed again, this time terminally, but without injury to their pilots; the last one only two years ago. The third was originally flown out to South Africa in 1969, using the ferry flight as a demonstration to potential operators along the way. This aircraft, ZS-WPO, was flown out by Roy Williams and was exhibited in the Australian trade pavilion during the Nairobi Agricultural Show, and then a few weeks later, at Cape Town’s Australian trade fair, before being delivered new to Westelike Provinsie Oesbespuiting, run by the Marais family in Malmesbury in the Cape. In 1977 the Marais` sold it to Agricura, and it eventually passed to Orsmond Aviation. The corrosive effect of chemicals eventually grounded the aircraft due to a difficult hopper/airframe repair and, having been parked at Bethlehem, the Airtruk was sold to well-known airline pilot, Fluffy McKerchar, who collected it on a trailer, removing both tailplanes as well as the fibreglass rear cabin. The Agtruk flew many hours under the care of Eugene Marais, whose dad bought the aeroplane. Now a doctor practicing in Mossel Bay, Doc Marais is South Africa’s only pilot to have earned a Master’s Degree from Stellenbosch University in Entomology, specialising in aerial spray patterns. The Agtruk “cost my dad R16,000 new”, recalls Eugene, who once attracted unwelcome attention from Danie Craven after landing a Piper Pawnee on the university’s rugby pitch. “The hopper was really designed for dry chemicals rather than liquids, and it was always a problem to stop leaks when we used it for fluids”. Eugene, now seventy years old, remembers the Agtruk’s many advantages: “We loved the rear cabin, with which we could carry around our equipment as well as ground crew. It often saved us having to drive our bakkie to wherever we were spraying. We could easily fix a ferry tank in the hopper to give us a 12-hour endurance. My dad did not believe in radios as we were flying low level all the time, although I recall the controllers getting peeved with us when we passed Jan Smuts one day. The airspace was very quiet in the seventies, and we would occasionally fly into Bloemfontein or elsewhere without having radio contact”. The Agtruk was carefully looked after during its tenure with the Marais family although there were a couple of incidents. Eugene recounts, “I was spraying in the Cederburg one day and had to jettison the load following a sudden change of wind direction as I was spraying directly towards a mountain ridge. 200 feet below the ridge, I realised I was not going to make it, even with an empty hopper. I managed to put the aeroplane down on a narrow and rocky 100-foot stretch of relatively flat surface, with a precipice on the approach and the mountain side at the far end. Just as I stopped, the wing caught a Protea plant which dented the leading edge. The farmer managed to get his tractor up to the aeroplane, and using a length of heavy steel railway track, smoothed a surface for me to turn the aeroplane around and takeoff once we had patched up the wing. The 3000 feet sheer drop helped to get my flying speed up at the end of the takeoff run. We also bent the undercarriage running across an Aardvark hole one day and flew the lopsided Agtruk around for a few hours before the factory told us to re-heat the leg and bend it back again - perfectly safely, which we did.” “It was great to fly”, says Eugene. “I shortened the stick so I could rest my forearm on my knee. I used to visit the zoo when I was a youngster and ride the elephants. The cockpit reminded me of those wonderful school years as it’s the highest point so it was easy to manoeuvre below wires in those days. We were sad to sell it, but the new Grumman Ag-Cats could lift much more weight”. Fluffy intended to fly the aircraft but realised that the restoration project would be a lot less fun than his many other retirement activities, which include motor racing, car restoration, and model boat sailing. The Airtruk thus remains parked under shade netting on his plot, awaiting an enthusiastic and committed aircraft tinkerer who might restore it to an airworthy condition. The aircraft would make a worthy air show performer for an enthusiast willing to invest in its future. Fluffy says he still has engines for the aircraft but can’t recall exactly when he acquired them.
John ‘Fluffy’ McKerchar: 1977 Air race winner I didn’t want to spend my retirement years playing golf”, says 65-year old John ‘Fluffy’ McKerchar, who last flew Airbus A340s with South African Airways. He left SAA in May 2006, following an illustrious career as a flight engineer, and then pilot on the Hawker 748, Boeing 707, 727s and 747. He will long be known as the pilot who flew a single-seat homebuilt to victory in the 1977 State President`s Air Race; notoriously difficult for a two-crew cockpit, never mind a single-seater. Fluffy still has his race-winning Taylor Titch, ZS-UDZ, built by Fanie van Rensburg in 1972. “It flew nicely”, he says. “However, it could be challenging to land with its unusual sprung steel undercarriage. Nick Turvey pointedly asked me how many hours I had, after he insisted on conducting a handicap test flight on the aeroplane prior to its race win. With lots of glider-flying experience, I managed to fly it on the rev-counter alone, taking advantage of every updraft. 3000 rpm on its 108 hp O-235 Lycoming, was the sweet spot, and I managed to achieve 166 mph against a handicap of 156 mph. I was never more than a quarter of a mile off track on the course which ran between the start at Baragwanath to finish at Durban’s Virginia the next day. I had flown the Titch some 700 hours and knew it very well - it’s demanding handling during landing was its only Achilles heel”, Fluffy says. Fluffy now indulges himself in his many restoration and building projects - many of them motor cars. He also loves to race model yachts and, in his younger days, raced power boats. His aeroplane collection not only includes the Airtruk and Taylor Titch - he also has a rare Jodel Bebe, ZS-UIJ; a Volmer Jensen ultralight powered by a 10 hp Rockwell Powerbee engine; a Nieuport 11 World War One airframe; an Avid Flyer, ZS-VLB; Hyperlite homebuilt, ZS-WCP; 1934 Kirby Kite sailplane, ZS-GAM; a rare Motor Spatz motor glider, and a Falke SF25B. He also has the completed fuselage tub of a Flying Flea hanging from his workshop roof, and under a pile of aircraft parts, an unfinished 7/8th scale Spitfire homebuilt. With aircraft a fairly low priority, Fluffy is charged up about finishing one of his many car projects - an original 1974 European Formula Atlantic Modus, once driven successfully by young Formula One racing driver, Tony Brise, who lost his life in the accident which killed Graham Hill at Elstree Airport in 1975. The racing car and its Cosworth BDA engine, and valuable Hewland gearbox, is being prepared for a historic racing event later this year. |
