Two-Stroke Diesels To Be Tested In LSAs

Powerplant Developments Ltd. (PPD) President and CEO Tim Archer announced at AirVenture 2008 that a Memorandum of Understanding was signed just days ago with Italian aircraft manufacturer Costruzioni Aeronautiche Tecnam S.r.l. Under the terms of their MOU, PPD will supply one pre-ASTM certificated Gemini 100 100HP engine for testing on a Tecnam P92 Eaglet LSA.

After flight evaluation testing is complete, Tecnam will then determine which of their LSA's will subsequently be offered with the PPD Gemini 100 diesel as an alternative engine choice for their customers.

The Tecnam P92 Eaglet is an all aluminum airplane that combines the best features of their high wing aircraft line into one improved platform suitable for primary and advanced training as well as cross-country needs. It received its US Airworthiness Certificate on 1/11/2008.

When the Gemini 125 engine is in the final stages of its FAR33 certification process, PPD will supply Tecnam with two engines for installation and evaluation on the Tecnam P2006T multi-engine aircraft (above), now under development as a certificated airplane.

"We couldn't be more excited and proud that such a well established aircraft manufacturer like Tecnam has shown such a high level of confidence in the Gemini Engine program," Archer said. "We are extremely confident that both the Gemini 100 and Gemini 125 will deliver the performance, reliability and value that Tecnam is looking for."

Archer went on to say that, "as you can imagine, this is a major step in the development of the Gemini engine family. It is even more exciting because it will give the (Gemini engine) program immediate exposure into the European markets where an efficient and reliable diesel/Jet A powered engine is critically needed by general aviation aircraft owners."

"We are anticipating the Powerplant Developments' Gemini engines will bring an exceptional level of performance and capability to Tecnam aircraft owners," said Paolo Pascale Langer, managing director of Tecnam S.r.l. "It is very low weight for a diesel and it provides greater efficiency and higher torque than is found in current available engines. Our aircraft owners have come to rely on Tecnam to deliver the best in class performance and value and I believe that the Gemini 100 and 125 engines will exceed their expectations."

Powerplant Developments is a UK based Company of four principals located in West Sussex. Managing partner Tim Archer is based in the United States. Their Gemini family of two-stroke diesel engines is currently in development starting with the Gemini 100HP engine which is being targeted specifically at the LSA market and certified via ASTM Standards. Other engines of the same basic two-stroke design and up to 600HP are envisioned as the line matures. Archer stressed that supplying general aviation with a reliable alternative diesel engine is the primary focus of the Company.

Comparing what he is able to report at AirVenture 2008 with what he envisioned during his show briefing last year, Archer said start-up issues such as suppliers and financing are now mostly resolved but slowed the development timeline by six to eight months. The company has hired an outside consultant charged with finding a suitable location to establish a US manufacturing facility as well as other startup issues and much progress has been made on all fronts. Archer stated that their UK facility is capable of producing up to 1400 engines per year but the market is envisioned to be much larger when non-aviation applications come online and as the family of engines matures.

"The Gemini 100 engine is on the test stand now," said Archer. An international dealer network is being assembled and spares support is receiving special attention. PPD hopes to have a limited production capability set up in 2009 with full production three to six months later.

The Gemini 100 weighs in at just over 155 pounds dry (with starter, alternator and fuel system) and 190 pounds wet with required ancillary accessories. The Gemini 125 -- essentially the same engine with turbo charging added -- weighs 170 pounds dry and 205 pounds wet. The Gemini 100 is a geared engine of 1.6/1 ratio. When asked if the gearbox would have time limitations as it does for a competitor, Archer stated that, "it would not."

The Gemini 100 and 125 are two-crankshaft, two-stroke, three-cylinder, six-piston opposed designs with mechanically driven superchargers required to maintain positive pressure for induction and scavenging. The combustion chamber is formed between the opposing pistons and inlet and exhaust ports are formed by orifices in the cylinder walls. The Gemini 100 maintains sea-level performance to 5,000 feet while the Gemini 125 -- with turbo charging added -- maintains sea-level performance to 15,000 feet. As currently envisioned, all engines above the Gemini 100 will be supercharged and turbocharged and any used for aviation will be certified via FAR 33.

FMI: www.ppdgemini.com, www.tecnamaircraft.com