Thielert Aircraft Engines' rapid climb to become a world leader in jet-fuel piston aero propulsion has been in close formation with that of its biggest customer, Diamond Aircraft. Now - having made its reputation as an original equipment supplier to the Austrian airframer - the German engine maker is firing up its retrofit business, particularly in the biggest general aviation market, North America.

Founded in 1999 by entrepreneur Frank Thielert, who 10 years earlier had started a Hamburg-based enterprise developing high-performance automotive racing engines using diesel technology, the breakthrough for the company came in 2001 when its Centurion 1.7 was selected by Diamond to power a diesel version of the single-engine DA40. Later that year the 135hp (100kW) engine became the sole option on the DA40's twin-engined sibling, the DA42 Twin Star.

© Thielert   
Thielert's success has been under-pinned by Diamond's selection of its Centurion 1.7 engine

Diamond's success - this year it will produce around 400 DA40s and 250 DA42s, with that figure ramping up next year when Chinese DA40 final assembly begins - has underwritten Thielert's growth. However, the company has continued on its mission to convert tens of thousands of private pilots and flying schools to diesel technology, winning US Federal Aviation Administration approval to re-engine Cessna 172 Skyhawks and the Piper PA28-161 with the 1.7. Last year, it struck a deal with the world's largest Cessna reseller, Van Bortel Aircraft of Arlington, Texas, to install the Centurion 1.7 in nearly-new aircraft, and with US flight school American Flyers to re-engine 55 172s.

Thielert's revenues have grown fourfold in three years, from €15 million ($20 million) to €72 million in 2006, with earnings before tax of more than €18 million - and aeroengines has overtaken the original automotive business in size. The company floated on the Frankfurt stock exchange in 2005 to fund further expansion. So far, it has sold over 1,500 of its Centurion 1.7 engines, with a successor, the 2.0, launched last year. The new engine, still rated at 135hp, but with larger capacity, will be used from now on in original equipment and retrofit installations. Output is running at 120 engines a month and, although Frank Thielert will not split original and retrofit production, Diamond's output figures mean it will be taking delivery of around 70 engines a month.

Last year saw a major expansion for Thielert, with the $10 million acquisition of Dallas-based Superior Air Parts, which makes replacement parts for Continental and Lycoming general aviation piston engines, and a €6.4 million investment in a new 2,500m2 (27,000ft2) factory in Altenburg, eastern Germany, just north of its main plant in Lichtenstein, Saxony, and next to the regional airport. Production at the new factory began in December, with Thielert taking on around 50 staff, in addition to the 120 at Lichtenstein, in one of the most economically challenged parts of Germany.

The company's second model - the 350hp Centurion 4.0 targeted at the Cessna 206 - has gone into production. This year will see 350 retrofit kits being built, but Frank Thielert says annual output will reach a "minimum of 700 or 800". Although there is no obvious candidate, he is "very positive" about finding an airframer prepared to fit the engine as original equipment. However, the company would need "two or three years" before it could cope with serial production.

A Centurion 3.2 has also been developed - pitched at the smaller market of mid-size piston singles such as the Cessna 182 - but other priorities mean the engine will not reach production until at least 2008, says Frank Thielert.

A less-publicised part of Thielert's business is its defence activities. General Atomics Aeronautical Systems, another customer for the Centurion 1.7, will begin fitting the engine to Warrior unmanned air vehicles in August for delivery to the US Army. Frank Thielert says he has been "surprised" at the growth in the UAV sector.

"I expect this to be a $70 million market [for engines] by 2010 with the potential for 1,500 engines," he says. "Defence is a significant part of our business."

Source: Flight International