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Lycoming set for UL 91 Unleaded Avgas Approval

23 March 2012

In a pressrelease dated March 22 2012 Lycoming Engines informs that they have submitted to EASA an application for approval of all their aircraft engines certified on AVGAS 80/87, Motorgasoline and some AVGAS 91/96 engines on an unleaded Aviation Gasoline grade UL91 meeting US standard ASTM D7547.

A fuel is legal for an aircraft if the fuel carries the engine manufacturers approval and the approval of the airframe producer. Unfortunately some airframe producers are no longer in business or current airframe producers some time sees a local market such as Europe as too small in order to change an airframe type certificate. In order to allow a safe fuel to be used in such cases EASA has issued Safety Information Bulletins. The latest in this subject is SIB 2011-01R1.

The initiative from Lycoming Engines shall be seen in light of a recent launch in France and the UK of the grade UL 91 unleaded AVGAS by the French AVGAS producer TOTAL.

The approval from EASA is expected within a few months.

Hjelmco Oil has proprietary unleaded Aviation Gasolines grade 91/96 and grade 91/98. These fuels have been in constant production since 1991 and were approved by Lycoming already 17 years ago. The performance of the Hjelmco unleaded AVGAS exceeds the performance of the grade UL 91 unleaded AVGAS and is thus approved by Lycoming Engines for all their AVGAS 91/96, AVGAS 80/87 and Motorgasoline rated engines.

With the upcoming approval from EASA general aviation pilots can now fly from southern France and the Mediterrian all the way up to the Polar Circle in Sweden and enjoy refuelling unleaded Aviation Gasoline in typical aircraft such as Cessna 172 and Piper PA-28.

It is estimated that about 50 % of the entire piston powered aircraft fleet in Europe have engines soon to be approved by EASA for using unleaded Aviation Gasoline.

Already today approved by EASA are also piston powered aircraft with engines produced by Rotax typically installed in ultralight aircraft.

To view the Lycoming pressrelease see the upper right hand corner and maps over refuelling locations in Europe.

For listening to a Podcast from Avweb in this issue see

For earlier information about this topic see

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