Submitting Campus

Daytona Beach


Electrical Engineering and Computer Science

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Publication/Presentation Date



This report contains an overview of the technology and engineering issues with nonturbine heavy-fueled engines for general aviation aircraft and Unmanned Aircraft Systems. In recent years, interest in these types of engines has grown, partly due to the cost, safety, and worldwide availability of gasoline fuels. Within 3 to 5 years, up to five engines will seek Federal Aviation Administration certification as heavy-fuel powerplants. Although there has been some progress, there is no universal standard for certification of these engines (under Title 14 Code of Federal Regulations (CFR) Part 33), or their installation into normal category fixed-wing aircraft or rotorcraft (under 14 CFR Parts 23 and 27, respectively). Additionally, the emerging demand to operate unmanned systems within the National Airspace System powered by these new powerplants requires knowledge of their characteristics and operation. A number of known engineering issues are listed for these engine types and the different types of airframes have been identified along with potential mitigation by design or operation. Finally, issues which are of specific concern to an aircraft with no onboard pilot are identified.


Washington, DC

Additional Information

Report number: DOT/FAA/AR-08/42