Dear Schempp-Hirth customer!
All member states of the EU have agreed to raise the percentage of ethyl alcohol (ethanol) added to the automotive gas until end of 2010 from 5 to 10 volume percent. This revision is based on Directive 2009/30/EG issued April 23rd 2009 which changed the EU Directive for automotive gas 98/70/EG.
In your national press it surely was published that for this reason from January 2011 and on another automotive gas premium fuel grade named “E10” will be available on the fuel stations. This fuel grade contains up to 10 volume percent ethanol. The common premium fuel grade with maximum 5 volume percent of ethanol will now be named “E5” and will be still available in the EU at least until end of 2013.
Tests of the engine manufacturer SOLO showed that the SOLO engines can be operated with the E5 premium fuel grade. Premium fuel with the E10 grade in contrast affected the components of the carburettors. For this reason premium fuel with the E10 grade may not be used for the operation of the SOLO engines.
So far no bad experience is reported for Schempp-Hirth gliders with Rotax engines, when they are operated with the E5 premium fuel grade. It is not known if the engine manufacturer has conducted any tests with the E10 premium fuel grade. For this reason the operation of Rotax engines with the premium fuel grade E10 is not permitted.
If you intend to operate your glider with automotive gas take care that the provided fuel complies with the requirements from the valid release of the Manuals issued by Schempp-Hirth and the engine manufacturer. Within the EU in addition make sure that the available automotive gas is labelled with the “E5” sign. Outside the EU the volume percentage of ethanol inside the automotive fuel may vary widely. Before refuelling your glider please carefully check the qualities of the available automotive gas.
It is not allowed to use any available fuel addition agent to attain E10 fuel serviceability for engines which are not cleared for the operation with E10 fuel by the manufacturer.
So far it is not known if the engines can be adapted to the E10 fuel and which effort this will take. The further procedure will be fixed when it has become clear if the E5 fuel grade will still be available after 2013.
EASA Info to this topic: 2007-01R1 : Use of Automotive Gasoline (Mogas) containing Bio-Ethanol