Continental Introduces Diesel For Helicopters


Continental Aerospace Technologies has introduced a diesel engine for helicopters at Aero Friedrichschafen in Germany. The CD-170R is expected to be certified in Europe next year. The turbocharged engine puts out 170 horsepower and is direct drive with no gearbox. That saves 37 pounds. “This is a major innovation milestone in Continental’s history that will allow us to serve even more pilots and operators in the general aviation industry,” said Dr. David Dörner, Vice President of Global Research and Development.

Like the airplane versions of the engine, the 170R has FADEC and the company is expecting a fuel burn of 7.9 gallons per hour or better. It will start with a time between replacement of 1,200 hours and that’s expected to increase with time in service. Flight schools and owner-pilots are expected to be the main customers.

Russ Niles
Russ Niles is Editor-in-Chief of AVweb. He has been a pilot for 30 years and joined AVweb 22 years ago. He and his wife Marni live in southern British Columbia where they also operate a small winery.


  1. What is the actual weight of the engine? Is it spark diesel? “7.9 gallons per hour” at what rpm?

    • Compression diesel requires a stronger construction that adds more weight. Diesel is also considered a dirty fuel because it requires less refinement.

      • I would almost guarantee it burns Jet A. Is it considered a “dirtier” fuel than leaded Avgas?

        • If by “dirtier” you mean sulfur content, then yes, diesel and naphtha tend to have higher levels of sulfur in them than gasoline. Just a product of the refining process. However, in the U.S., refiners have been required to install units to remove the sulfur from highway diesel, which is the largest volume of the product. Off-road diesel, mostly used for farming and other uses can still have the higher sulfur content. Jet A has a very low allowable sulfur content by regulation and always has. I would speculate that the “new” engine will be able to run on either fuel, but only Jet A would likely be available at the airports.

    • If it flys 3 hours a day, that is 400 days of flying….
      But modern common-rail diesels in cars are good for 20 years, and counting, so will be bad luck if early replacements turn out to have problems.
      Avgas motors in small helicopters are cheaper to run than turbines, but not by as much as you would expect given relative fuel consumption, because Avgas is so expensive, especially outside US.
      So think Continental are on to something, even though all their earlier talk was of one of their boxers, not a straight 4, as the ideal helicopter motor…

  2. In addition to the higher weight, the gearbox has often been a reliability issue for diesel engines on aircraft. It will be interesting to see how the blades of a helicopter handle the higher power pulses of the diesel engine, especially in a direct drive setup. Those stronger pulses have been a big problem with props on conventional aircraft.

    • John Mc, I believe all helicopters have gearboxes that are fundamental to the design of their rotor system, Richard Phillips alluded to in above comment. Thus, Continental did not need to include a gearbox as part if its engine design and could advertise a weight savings of 37lbs.

  3. Certainly a bonus burning Jet A-1 in the United Kingdom. Our tax structure makes Jet fuel about half the cost of Avgas, so very attractive to flight schools.