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News of August 15, 2007

Oshkosh season: Of Facts and Rumors around the Diamond Air family of diesel aircraft. Part One

DieselAir regularly receives messages of subscribers owning or operating diesel aircraft. Since several hundreds are now flying worldwide, one can detect recurring topics through messages expressing satisfaction, suggestions for improvements, and problems. As a rule we publish neither rumors nor opinions but try to stick to facts, and to intentions as expressed by vendors and manufacturers.
The aero-diesel market is presently dominated by Thielert Motoren (Centurion, Germany) for the engines, with SMA (France) a distant number two and DeltaHawk (US) and Wilksch (UK) following; and, for diesel-equipped aircraft, by Diamond Air with its DA 40 single and DA 42 twin. The Thielert Motoren sales figure now runs at Euros 80mm p. a. The company is publicly traded with a market capitalization of Euros 500mm in June. The firm just raised 28mm equity through their last stock offering. Thielert has an OEM agreement with Diamond. The Thielert engine is now proposed by Cessna as an STCd option on the 172. We can expect the Thielert V8 to be STCd and proposed for the Cessna 206 within 2 years, and perhaps less; also on the Cirrus SR22. Several hundred Thielert 135 HP are flying today. The Cessna 172 Thielert retrofit is proposed in the US by EPIC Aviation, Africair and Cessna dealer Van Bortel. The SMA diesel is STCd on the Cessna 182 since January 07 but available only as a retrofit, and will certainly be STCd and available as an OEM on the Maule MX9 by end 07. We guestimate that some 50 SMAs are flying worldwide today. No other diesel solution is STCd in the US today but several are available on an Experimental basis.
Recently, it appeared that several British customers, mostly fleet operators, are running into quality and service problems with their Diamond Air DA40 and 42 diesel airplanes. These aircraft are equipped with the Thielert 135HP. Mike Millen of Millen Aviation Services, a reputable FBO and flight academy and part of The Millen Corporation says he is preparing to take legal action to resolve this long running situation. We have no negative input from owners of Thielert equipped Cessna 172 or Piper Cherokee/Warrior which are the two main models on the retrofit market, nor of the few owners of the French Robin DR400 Ecofuel diesel. We have no negative signals from owners of Cessna 182SMA. For other engines or planes the numbers flying are not significant enough yet. It is clear anyway that reported problems are on Diamond aircraft singles and twins.
The August 07 issue of the major French periodical Aviation et Pilote publishes a special report candidly talking of a major dispute between Thielert and Diamond Air, illustrated by the fact that Diamond Air is openly advertising their prototype of a diesel engine developed jointly with MB Motoren (Mercedes Benz engine research division). The French owners deal through Aerosport, the Diamond Air importer and distributor in France, who is said to be compelled coordinating complaints regarding customer service and has an overview on all incidents in France. The French customers, according to the periodical, report the same kind of trouble than the British, with more reports on the twin-engine DA 42.
The recurring topic in these British and French stories sounds like a lack of responsiveness from Diamond’s customer service. Since many of them operate DA 40s as trainers, meaning a rather intensive flying time, this means much too much downtime for aircraft which may be grounded only for a minor problem.
One factor seems that the early Thielert 1.7 liter, on Diamond aircraft, was cooled with a refrigerating liquid which was not the one prescribed by Thielert and was too corrosive. Thielert reports that this has caused pitting corrosion on engine parts, and therefore breakdowns without dramatic consequences.
We have therefore solicited interviews with Diamond Air and Thielert Motoren. Chief Executive Officers Frank Thielert (FT) and Christian Dries (CD) were accessible, and we will publish their interviews. See our next story with the first of them.
Andre Teissier du Cros, DieselAir Newsletter, August 07.

posted at 6:27 AM

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Mission Statement

Every month: news, facts, and comments on the coming revolution for piston-engines aircrafts between 130 and 400 HP: Retrofitting a diesel engine to run on Jetfuel or Kerosene, reduce Gallons/Hour by some 30%, eliminate ignition systems (magnetos, spark plugs) and their problems, eliminate mixture control, increase TBO to 2,400-3,000 hours, increase performance between 6,000 and 12,500 ft., and drastically reduce Operating Costs.

The letter is intended for piston engines aircraft owners, manufacturers, fleet operators and FBOs, re-manufacturers of engines for these aircrafts, manufacturers of engine components and ancillaries, and all professionals acting in decisions of engine exchange or refitting at TBO, in North and South America, Pacific Rim, African continent, and all parts of the world were Avgas, Mogas, Kerosene and Jetfuel are available.

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