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[Federal Register Volume 76, Number 154 (Wednesday, August 10, 2011)]
[Notices]
[Pages 49525-49526]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2011-20324]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

Advisory Circular 20-24C, Approval of Propulsion Fuels and 
Lubricating Oils

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of issuance of advisory circular.

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SUMMARY: This notice announces the issuance of Advisory Circular (AC) 
20-24C, Approval of Propulsion Fuels and Lubricating Oils. This AC 
provides guidance on regulations and policy applicable to adding fuels 
and oils to type certificates as engine, aircraft, or auxiliary power 
unit (APU) operating limitations. It also provides acceptable methods, 
but not the only methods, that may be used to approve aircraft, 
engines, or APUs to operate with specified propulsion fuels and 
lubricating oils.

DATES: The Engine and Propeller Directorate issued AC 20-24C on July 
29, 2011.

FOR FURTHER INFORMATION CONTACT: The Federal Aviation Administration, 
Attn: Mark Rumizen, Aviation Fuels Specialist, Engine and Propeller 
Standards Staff, ANE-110, 12 New England Executive Park, Burlington, MA

[[Page 49526]]

01803-5299; telephone: (781) 238-7113; fax: (781) 238-7199; e-mail: 
mark.rumizen@faa.gov.
    Comments were submitted to the FAA during the period the draft AC 
was posted for public viewing on the FAA's Aviation Safety Draft 
Documents Open for Comment Web site. The disposition of these comments 
can be viewed at the FAA's Regulatory and Guidance library Web site 
(http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgAdvisoryCircular.nsf/Frameset?OpenPage).

SUPPLEMENTARY INFORMATION: AC 20-24C cancels AC 20-24B and describes 
established methods of adding fuels and oils as engine, aircraft, or 
APU operating limitations. These established methods reflect procedures 
and practices employed by the Engine and Propeller Directorate (EPD) 
for oversight of successful aviation fuel and lubricating oil 
certification projects conducted over many years. These procedures and 
practices have essentially relied on fuels and oils grade or brand 
designations that were identified by industry voluntary consensus-
based, military, or other governmental standards.
    A draft of this AC was made available for public comment on 
September 1, 2010, for a period of 60 days. The FAA received many 
comments regarding the use of other, new and novel methods to add fuels 
and oils as engine, aircraft, or APU operating limitations in lieu of 
the methods described in the AC. However, the EPD cannot develop 
guidance describing other, new and novel methods until we gain 
sufficient certification oversight experience with these projects. 
Therefore, the final AC does not contain guidance on these new and 
novel methods to add fuels and oils as engine aircraft, or APU 
operating limitations.
    How To Obtain Copies: A paper copy of AC 20-24C may be obtained by 
writing to the U.S. Department of Transportation, Subsequent 
Distribution Office, DOT Warehouse, SVC-121.23, Ardmore East Business 
Center, 3341Q 75th Ave., Landover, MD 20785, telephone 301-322-5377, or 
by taxing your request to the warehouse at 301-386-5394. The AC will 
also be available on the Internet at http://www.faa.gov/regulations_policies (then click on ``Advisory Circulars'').

    Authority: 49 U.S.C. 106(g), 40113, 44701-44702, 44704.

    Issued in Burlington, Massachusetts, on July 29, 2011.
Peter A. White,
Acting Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.
[FR Doc. 2011-20324 Filed 8-9-11; 8:45 am]
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