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Subject: Re: Your Petition for Exemption, Docket No. FAA-2012-0582

From: Ross McCurdy <rkmccurdy@yahoo.com> - Monday 07/02/2012 12:50 PM

History: This message has been replied to.
From: "John.Linsenmeyer@faa.gov" <John.Linsenmeyer@faa.gov>

To: rkmccurdy@yahoo.com 

Sent: Friday, June 29, 2012 1:30 PM

Subject: Your Petition for Exemption, Docket No. FAA-2012-0582

Mr. McCurdyMy office is reviewing your petition for exemption from 14 CFR 61.113. 

In your petition, you note that the aircraft you intend to use has been modified with a diesel engine and will 

be consuming an fuel not normally used in general aviation aircraft. We would like to have more 

information for the docket on the airworthiness status of the aircraft. Could you please send me 

information about the aircraft's airworthiness status with regard to the engine modification, the 

nonstandard fuel, and any other relevant information.

Thank you!

John Linsenmeyer

FAA Flight Standards Service, AFS-810

Airmen Certification & Training Branch

55 M Street SE, 8th Floor 

Washington, DC 20003

john.linsenmeyer@faa.gov

202-385-9612
1 

FAA 

Aviation Safety

SPECIAL AIRWORTHINESS 

INFORMATION BULLETIN 

SAIB: NE-11-56 

SUBJ: Semi-Synthetic Jet Fuel Date: September 14, 2011 

This is information only. Recommendations aren’t mandatory.

Introduction 

This Special Airworthiness Information Bulletin (SAIB) advises aircraft operators, Fixed Base 

Operators (FBOs), FAA repair stations and FSDOs, and Foreign Civil Aviation Authorities, that jet 

fuel made from hydroprocessed fatty acid esters and fatty acids (HEFA) or Fischer Tropsch (FT) 

synthetic blending components that meets the requirements of ASTM International Standard D7566 

is acceptable for use on aircraft and engines certificated for operation with D1655 Jet A or Jet A-1 jet 

fuel, provided that it is re-identified as D1655 fuel. When re-identified as D1655 fuel, D7566 jet fuel 

meets all the specification requirements of D1655 and therefore meets the approved operating 

limitations for aircraft and engines certificated to operate with D1655 fuel, unless otherwise 

prohibited by the engine or aircraft type certificate (TC) holder.

Background 

The FAA relies on ASTM International to develop fuel specifications that applicants may designate 

as operating limitations for their approved products. These aviation fuel operating limitations may be 

listed in the product’s Type Certificate Data Sheet (TCDS), Installation Manual, service instructions, 

or as limitations associated with a supplemental type certificate (STC). 

ASTM International issued ASTM Standard Specification D7566, “Standard Specification for 

Aviation Turbine Fuel Containing Synthesized Hydrocarbons,” for drop-in jet fuel from alternative 

feedstocks in September 2009. This specification defines properties for semi-synthetic jet fuel made 

from blending conventional jet fuel with synthetic blending components that are specified in 

individual annexes. These semi-synthetic jet fuels specified in D7566 possess essentially identical 

composition, properties, and performance to conventional jet fuels. This specification initially 

included only one annex for synthetic fuel from coal, biomass, and natural gas produced using the FT 

process. On July 1, 2011, a second annex was added to this specification to permit the use of HEFA 

synthetic blending components. HEFA is considered a biofuel because it is made from plant oils or 

animal fats.* Both D7566 and the existing specification for conventional jet fuel, ASTM 

International Standard D1655, “Standard Specification for Aviation Turbine Fuels” are crossreferenced to allow D7566 fuels to be re-identified as D1655 fuels when they enter the distribution 

system. When re-identified, D7566 fuels made with HEFA or FT blending components meet existing 

FAA-approved operating limitations, unless otherwise prohibited by the engine or aircraft TC holder. 

Recommendations 

The following recommendations apply to HEFA or FT fuels meeting ASTM specification D7566 that 

are re-identified to ASTM D1655 Jet A or Jet A-1 fuels (unless otherwise prohibited by the engine or 

aircraft Type Certificate (TC) holder): 

1. These fuels are acceptable for use on those aircraft and engines that are approved to operate 

with Jet A or Jet A-1 fuels meeting D1655. 
2 

2. Operating Limitations in Aircraft Flight Manuals, Pilot Operating Instructions, or Type 

Certificate Data Sheets that specify ASTM D1655 Jet A or Jet A-1 fuel are acceptable for use 

with these fuels. 

3. Current aircraft placards that specify Jet A or Jet A-1 fuels are acceptable for use with these 

fuels. 

4. Operating, maintenance or other service documents for aircraft and engines that are approved 

to operate ASTM D1655 Jet A or Jet A-1 fuel are acceptable for use when operating with 

these fuels. 

For Further Information Contact 

Mark Rumizen, Aerospace Engineer, FAA, Engine & Propeller Directorate, 12 New England 

Executive Park, Burlington, MA 01803; phone: (781) 238-7113; fax: (781) 238-7199; 

email: mark.rumizen@faa.gov. 

*HEFA is also referred to as Hydroprocessed Renewable Jet (HRJ) and Bio-SPK (synthesized 

parrafinic kerosene)