Richard Murdoch wrote: > I wonder how much re-engineering they would have to do to use the Mercedes > CDI for aviation purposes?
I saw a blurb about a VW TDI re-engineered for use as an aviation engine, for the European market, once. It had a reduction gear, as is common practice when using an auto engine in an airplane. (Otherwise the engine never gets to run fast enough to reach its torque peak.) I don't know how they handled the fuel injection computer. For certification in the U.S., I think it would need backup power at least, and maybe dual redundant computers. The target fuel was Jet A, since it's readily available at airports, cheaper than avgas, and has good low temperature characteristics. It was being pitched as an ideal engine for glider tugs, because of the low fuel burn and because the water cooled design meant no concerns about shock cooling -- always a problem with tugs, since they make a long climb, then immediately descend.