From George W Braly
When we look at this problem - - we boil down the issues to a set of design requirements for a workable replacement avgas for 100LL.
Design Requirements for a Functional Drop-In Replacement for 100LL Avgas:
1) Detonation - - same-same as 100LL;
2) Material compatibility - - close or same-same as 100LL;
3) Economics - - close to 100LL. Close means ? ~ about 10-15% premium or less;
4) Fungible. Has to be mixable in the FBO tanks and the wing tanks. Otherwise a transition to a new fuel becomes a logistical nightmare.
5) Producible. Has to be able to be made inside the fence of existing refineries. Nobody is going to spend 100’s of millions to build new production facilities. This requirement is related to item 3) above; and,
6) Transparent. Has to be transparent to the pilot, the engine, & the airframe when compared to 100LL.
Frankly - - we can do an assessment of five of those six requirements in two or three days of testing at our facility. The material compatibility testing takes longer, but even that is subject to some pretty straightforward assessments.
But then actually doing all of the formal certification work is challenging.
All of the testing todate continues to demonstrate that G100UL(R) avgas meets each of those six requirements.
Swift decided to pursue an ASTM specification - - hoping then that someone will decided to undertake the expensive and time consuming work to do all of the FAA certification testing to actually get the fuel approved to that it can be added to the limitations section of the engine and airframe type certificates, then legally flown in the aircraft.
GAMI has taken a different approach. We decided to do a parrallel process. We are doing the heavy lifting certification work with the FAA. At the same time we have the ASTM process moving forward. The data we generate for the FAA certification effort can be used for most or virtually all of the ASTM data package. But the ASTM data package does not get you an FAA certification.
We continue to make good progress with the FAA certification effort. At the same time, we continue to move the ASTM specification approval process forward.
Regards, George