Saturday, June 30, at 9 a.m., Lars Hjelmberg, founder of Hjelmco Oil, will take part in a seminar on the development of unleaded aviation fuel at the Santa Monica Museum of Flying.
In 1979, Hjelmco Oil, developed an UN-Leaded 80/87 grade AVGAS. In 1991, the company developed an 91/96 grade UN-Leaded AVGAS, which is VERY close to 100 Octane. Coninental, Lycoming, Rotax and radial engine manufacturer Kalisz have all cleared the Hjelmco AVGAS 91/96 UL for use in some of their engines. The fuel has been widely used throughout Sweden for decades and millions of flight hours, including by the Swedish Air Force, and is the preferred fuel for general aviation there.
The fuel currently used in piston-powered aircraft, 100LL (low lead) AvGas, is the last leaded fuel in production. For years, environmental protection agencies worldwide have been working with refiners and other regulatory agencies to develop an un-leaded replacement for 100LL.
Tetraethyl-lead (TEL) used in 100LL AvGas acts as an octane booster to prevent engine detonation and pre-ignition. It also provides improved heat transfer for valve seats and piston rings. Due to the relatively small demand for AvGas, the TEL used in the AvGas has a very limited production.
There has been a lot of news recently about unleaded alternatives to 100LL, including a UL 91, which is being pushed by Lycoming Engines and TOTAL in Europe (see this news story – http://www.aopa.org/aircraft/articles/2012/120419lycoming-eu-bless-ul-91.html), 94UL, which is being pushed by Continental, a new 100UL being developed by a startup called Swift Fuel, and G100UL being developed by GAMI.
Additionally, recent national publications like Bloomberg have highlighted the potential health risks of leaded aviation gasoline. http://www.bloomberg.com/apps/news?pid=newsarchive&refer=&sid=aCfotEYJYr3Y
Lead emissions from piston-engine aircraft and leaded aviation gasoline are Federally-regulated. EPA received a petition to determine whether lead emissions from piston-engine aircraft endanger human health and the environment. The EPA is currently conducting a national-scale analysis of the local impact of lead emissions from piston-engine aircraft. It’s time to understand what the alternatives are to 100LL and where we are in the certification process.
The Museum of Flying is located ar 3100 Airport Avenue@ SMO Airport.