Swedish Firm Touts Unleaded Avgas

[Tom Turner]

Sweden's Hjelmco Oil says it has found the holy grail of aviation fuel: unleaded avgas. Lars Hjelmberg, the company's founder, says his company's 91/96 unleaded product can safely fuel more than 90% of the world's piston aircraft. The fuel is in widespread use in Europe, but so far has not received approval for use in the U.S.

http://venice.patch.com/articles/oil-company-head-unleaded-aviation-gas-available-for-most-piston-planes

[Paul Hekman]

Isn't something like 70% of U.S. avgas used by aircraft that can't use 91/96?

[Tom Turner]

I've seen that figure elsewhere without citation as to the source.  I suspect that since most larger, cross-country airplanes require more than 94 octane in current fuel formulations, that the 70% estimate is likely close.