The Care & Feeding of Diesel-Fueled Aircraft Engines

DeltaHawk was featured in September 2015 issue of Cessna Flyer

DeltaHawk contributed to the September 2015 issue of Cessna Flyer Volume 12, Issue 09.
Please read the excerpt below.

No spark plugs, no plug wires, no magnetos; no wonder diesel engines require less service than an Avgas engine.

In spite of the fact that these engines have a lot of advantages over an Avgas-fueled engine, today in the United States only one OEM sells a diesel-powered airplane. (Cessna Aircraft stopped taking orders for its 182 JT-A diesel engine Skylane last spring, and the project appears to be on hold. – Ed.)

Diesels are more fuel efficient, require less maintenance and are more dependable since there are far fewer moving parts.  And because Jet-A fuel is a lubricant rather than solvent, internal engine rust is eliminated.

I interviewed John Weber, the diesel engine service expert on the 155 hp liquid-cooled CD-155 at Continental Motors; Thierry Saint Loup, chief of North American support for the SMA 230 hp SR305-230 oil- and air-cooled engine; and Dennis Webb, president and CEO at DeltaHawk Engines to learn what it takes to keep a diesel engine running well.

They all said essentially the same things. Critical maintenance items include observing the best clean-room techniques possible when dealing with diesel fuel systems and keeping the induction filter clean.

Saint Loup mentioned that maintenance procedures on an SMA diesel are more akin to servicing a turbine power-plant, and that as long as the fuel system and inlet air filter are kept operating-room clean, "a diesel engine will run a long, long time."

Saint Loup also told me that SMA estimates that maintenance man-hour costs are 50 percent less than the costs to maintain an Avgas-fueled engine.

Service intervals on DeltaHawk's V4 engine

According to a service interval document supplied by Webb, DeltaHawk's plan for the V4 engine is very similar to the other two engines except a few of the intervals are shorter, including 50-hour oil changes—and in addition to the engine oil change, oil is also changed on the fuel pump and supercharger.

Diesel engines haven't been widely used, but interest in the technology—due in part to recent auto-industry improvements that offer higher power-to-weight ratios more suitable for an aircraft application—is growing.

Diesel's significant benefits, including increased fuel efficiency, decreased maintenance and more dependability are being welcomed by many in the General Aviation industry.

Read the full story in the September 2015 issue of Cessna Flyer Volume 12, Issue 09.
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