Textron Lycoming extends the use of unleaded Aviation Gasoline

06 April 2017

Update 2017-April-06

A new updated version of Service Instruction 1070 is available. Revision V can be downloaded from Textron Lycoming SI 1070-V in the upper right corner. As before: Hjelmco AVGAS 91/96 UL meets and exceeds the requirements of grade UL91 so all engines listed under grade UL91 may also operate on Hjelmco 91/96 UL.

Update 2016-July-09

Textron Lycoming has during 2016 released an updated version of Service Instruction 1070. Revision T can be downloaded from

Textron Lycoming SI 1070-T .

Hjelmco Oil AVGAS 91/96 UL meets both standard ASTM D7547 for grade UL91 and ASTM D910 for grade 91/98 but without lead and dye. The Lycoming SI 1070-T shall thus be read that the Hjelmco fuel covers all engines listed under grade UL91 plus the addtional listed under Hjelmco 91/96 UL.

One of the largest aircraft piston engine manufacturers in the world, Textron Lycoming, is in its new Service Instruction SI 1070R dated April 16 2012 extending the use of unleaded Aviation Gasoline grade UL91 to a large number of their popular engines.

Already year 1995 Hjelmco Oil pioneered with the first modern Textron Lycoming approved unleaded Aviation Gasoline, Hjelmco 91/96 UL, and now 17 years later a similar fuel meeting US standard ASTM D7547 is making its way into the headlines.

The position taken by Textron Lycoming will be highly appreciated by the market and will remove uncertainty of aircraft owners and increase value of their aircraft in the same way it has done for users of unleaded Aviation Gasoline Hjelmco 91/96 UL.

Unleaded AVGAS UL91 is today mainly produced in the southern parts of Europe, and supplied in France, UK, Germany and Switzerland. Hjelmco 91/96 UL has since decades its established market place in nothern Europe and Scandinvaia.

Important is also that Textron Lycoming in their new Service Instruction after recommendations from Hjelmco Oil is mandatoring the use of oil additive meeting Lycoming Service Instruction 1409 in combination with the use of unleaded AVGAS.

Piston engine oils meeting the additive requirement may be found among others in oils such as Total Aero AD 15W-50, Total Aero XPD80, Total Aero XPD100 provided by Hjelmco.

Service Instruction 1070-R can be downloaded from the upper right hand corner.