Bits and Pieces
More, Much More About Mogas STCs
By Jack Dueck, Editor – Bits and Pieces, EAA 337912, EAA Canadian Council
Editor Jack Dueck adding fuel to the ethanol fire
Last issue’s column on mogas supplemental type certificates (STCs) brought a number of comments, all of them warning of the use of ethanol as a cause for concern, which hasn’t been sufficiently mitigated by a heavy ratio of avgas to mogas.
Scott wrote: “…the fact is that auto gas is unstable and unsafe since a fair amount is blended with ethanol.”
Andre wrote: “…important not to leave mogas in tank, filter, or carburetor. If you have two tanks, cruise on mogas, and take off and land on avgas.”
Kent gave the following website for high-quality ethanol-free and lead-free auto gas: www.AviationFuelClub.org.
And finally, the following warning regarding the use of auto fuel in your aircraft has been published a couple of times before in COPA Flight:
If you’re one of many small aircraft users that buy automobile gasoline at the nearby gas station for use in your aircraft, please note that gasoline with ethanol continues to proliferate. Be careful that you don’t get ethanol by mistake.
In Ontario and Quebec, Petro-Canada stations with 94 octane at the pumps will have 10% ethanol in all the grades. In retail stations that don’t have 94 octane, the 91 at Petro-Canada stations will likely not have ethanol.
The only way to be sure at any station or about any brand is to test the gasoline. This applies nearly everywhere in the country. This isn’t hard to do. Here’s an easy test for determining the presence of alcohol in fuel:
In a small-diameter transparent cylinder, put approximately 10 mL [millilitres] of water and clearly mark the level. Add approximately 100 mL of the test fuel. Shake vigorously, then let stand. If after settling it’s apparent that the water volume has increased, alcohol is
In 2010 and 2011, because of provincial and federal mandates, more stations in the Edmonton area and in New Brunswick will start to have ethanol in the gasoline. More stations will be joining Petro-Canada in the Montreal area and the rest of Quebec.
So beware, just because it was okay before to use automobile gasoline, it might not be now or in the near future.
Visit Transport Canada’s website for more information on this issue.
I thank all of these responders. I encourage interested readers to pursue their research on this topic if they’re contemplating the use of mogas in their aircraft.