U.S. federal aviation administration asks for comments on diesel-powered aircraft policy

Diesel Fuel News, March 17, 2003

According to a notice in the March 12 Federal Register, comments on FAA's diesel aircraft policy (www.faa.gov/certification/aircraft/sadProposed.htm) proposal are due by April 11. Among the issues: Whether to allow anti-icing additives in the kero-jet fuel expected to be used in diesel aircraft.

Anti-icing additive would overcome a tendency for kerosene-like fuels to absorb more water than aviation gasoline. "Mandating the use of anti-icing additives would be an acceptable method to show compliance; however, the use of these additives is generally being curtailed in some countries for environmental reasons," the proposed FAA policy says. Thermal stability additives (as used in military jet fuels) also would need to be evaluated for diesel-powered aircraft. Cold-flow also must be ensured, and new cetane requirements must be specified for currently-unspecified kero-jet fuel. "Using the appropriate cetane rated fuel i n a diesel engine is critical to developing the appropriate power. It is not anticipated that commercial turbine fuels will be given a cetane rating; therefore, aircraft diesel engines will be approved and certificated to operate on a specific turbine fuel(s)," FAA says. Airframe safety issues also are factors, as diesels can put more vibration stress on airframes than gasoline engines, the notice says. For more information, contact: Peter Rouse: peter.rouse@faa.gov.