The bulletin
Text extracted from the PDF.
SPECIAL
AIRWORTHINESS
INFORMATION
BULLETIN
REGULATORY SUPPORT DIVISION P.O. BOX 26460 OKLAHOMA CITY, OKLAHOMA 73125-0460
U.S. Department of Transportation Federal Aviation Administration
No. CE-00-19 March 31, 2000
SAIB’s are posted on the internet at http://av-info.faa.gov This is issued for informational purposes only and any recommendation for corrective action is not mandatory.
Introduction:
The purpose of this Special Airworthiness Information Bulletin (SAIB) is to alert registered owners/operators of airplanes FAA approved for the use of high-octane automobile gasoline (autogas).
The FAA Small Airplane and Engine and Propeller Di rectorates have approved the use of 82UL gasoline (fuels meeting ASTM specification D6227) as an alterna tive to autogas (fuels meeting ASTM specifications D439 and D4814).
Aviation 82UL gasoline may not be used as a substitute fuel on airplanes requiring autogas with an aviation lean {motor method (MON)} octane rating greater than 82 or an antiknock index {(RON+MON)/2 } greater than 87 . Using this fuel on those higher performance engines originally approved for use with higher-octane fuels could result in engine detonation and associated destructive damage.
Aviation 82UL gasoline is only approved for use in airplanes incorporating supplemental type certificates (STC) approving the use of autogas with an aviation lean octane rating of 82 or less or an antiknock index of 87 or less . The minimum octane requirement unique to an y airplane (and engine) approved for autogas is placarded.
Background:
Numerous STCs and several airplane and engine type certificates (TCs) have been issued approving the use of unleaded autogas. Airplanes and engines appr oved for autogas use have met the FAA certification requirements for engine detonation, e ngine cooling, fuel flow, hot fuel testing, fuel system compatibility, vapor lock, and performance.
Many of these approvals are for regular grade unleaded autogas in lieu of Grade 80/87 aviation gasoline.
However, some of these approvals are for premium grade autogas in lieu of 91/96 or 100LL (100/130) aviation gasoline. Gasolines meeting the specifica tion 82UL are intended for airplanes using lowercompression, lower-performance engines that were or iginally approved for use with Grade 80/87 aviation gasoline.
Autogas 82UL is produced from autogas stocks, but is more tightly controlled and does not allow many of the additives. Use of this fuel on higher performance engines originally approved for use with higher-octane fuels could result in engine detonation and associated destructive damage. Therefore, 82UL gasoline may not be used as a substitute fuel for autogas approvals on airplanes that require fuels with an octane rating greater than 82, or an antiknock index greater than 87.
Recommendation:
The FAA highly recommends installing placards stating the use of 82UL is or is not approved on those airplanes that specify unleaded aut ogas as an approved fuel. Please contact the STC/TC holder directly for further information regarding the use of 82UL gasoline.
A majority of FAA STC approvals for autogas have b een issued to either the Experimental Aircraft Association (EAA) or Petersen Aviation, Inc. Placards and instructions may be obtained for those STC's as follows:
EAA Service Bulletin: 2000-1 dated March 1, 2000 Petersen Aviation Service Bulletin: P-2000-1 dated February 15, 2000
For Further Information Contact:
Scott Sedgwick, Aerospace Engineer; FAA Aircraft Cer tification Service, Small Airplane Directorate, 901 Locust Street, Rm 301, Kansas City, Missouri, 64106; telephone: (816) 329-4132;
facsimile: (816) 329-4090; email: scott.sedgwick@faa.gov