No MoGas WHY ?

airbusflyboy

Why are we not seeing MOGAS at our local airports ? It is very rare to find it , makes no sense as there are plenty of aircraft owners with a MOGAS STC

Scott Sherer

Hmmm. That's a very good question and I haven't got the foggiest idea. Does anyone else have any thoughts on the subject?

Pegasso62

If you let mogas set an extended period of time you'd wish you never used it. It eventually forms a clear amber colored leathery substance that is next to impossible to remove from the tanks, lines, selector valves, gascolaters, filters, pumps, carbs and injectors. In Alaska mogas is treated the same as avgas, clean. Super clean! Very extensive protocol is followed to keep even the slightest bit of condensation and debris out of aviation fuel storage, Not the case in the lower 48. Lower 48 automotive gas WILL have some ethanol in it. If someone tells you otherwise don't believe them, they don't know. (Once upon a time refiners worried about water in gas storage and transport. This is no longer an issue. Ethanol absorbs water, ethanol mixes with gas, you can not buy automotive gas without water in it! sometimes LOTS of water in it! Fuel sensors and onboard computers deal with this deferential beautifully, only a race car driver could tell the change in performance.) Liability for refiners, storage facilities and transporters for avgas are huge, the same liabilities for automotive fuel... virtually zero! If maintenance expenditures is not enough to dissuade automotive gas usage, then consider your desire to have an engine failure on a night time cross country. Highly refined avgas is costly... it's also worth it.

Scott Sherer

Thanks for your comments.

airbusflyboy

That might be a credible argument IF one allows the aircraft to sit with MOGAS in the tanks , otherwise burning it all or a 50 / 50 mix with AVGAS would bring annual savings ........ it appears to be a conspiracy of sorts that MoGas is not readily available

Pegasso62

You are right airbusflyboy, Letting automotive gas sit for extended amount of time is certainly worse, in that it gums up in the system, but you are missing my point that avgas has virtually NO INGREDIENTS that can form gum or varnish to begin with. Automotive gas is minimally refined, where as avgas is one of the most highly refined fuels there is.
Using a 50/50 combination of mogas/avgas just means you are putting in half as much contaminates as mogas alone. Avgas is VERY CLEAN and has completely different regulations and protocols for refining, storage and transporting. One fuel guarantees you'll never have gum or varnish build up in in your system, the other guarantees that you will. It's probably not enough to effect most of us, then again I know personally of two planes that went down from dislodged gum/varnish in a fuel system. Not all fuel starvation accidents are empty fuel tanks.

gthomas81

As an Airport Owner who offers MOGAS, I can tell you the only thing that makes it worth our time is we don't have to carry gas any longer for our Mules, mowers and tractors. If our infrastructure was not subsidized by the state, we could not afford to have the extra tank. We have over 80 planes on our field and if it wasn't for a Skydiving operation 100LL would not be worth our time. There is just no money in GA fuel sales unless you are fueling the big Jet A users. Airports supply MOGAS and 100LL as a convenience to the customer, not to make money.

We advertise 91 Octane MOGAS and carry the 91 because most Rotax drivers want it. This is the first I have heard about the alcohol but it does not surprise me. There is always some contaminants in fuel because different kinds move through the same lines with water plugs to separate them. I will have to ask the distributor if alcohol is intentionally added to MOGAS.

I am not a fuel expert but I know they do change certain aspects of MOGAS throughout the year for warmer and colder temps. This is why you definitely want to buy at an airport that moves a fair amount of fuel.
Otherwise you risk vapor locking your plane if you happen to get a winter blend on a hot day in late March or April.

The person who mentioned the tar like substance above it 100% correct. I have seen a fuel line completely plugged in a plane that was not being flown regularly.

As for myself, I always pay the extra cost for the 100LL.

Kentwkalb

I am on the board of our small airport in Northeastern KY. We are fortunate to have enough operations we do profit form 100LL sales. I hope we aren’t the only FBO to see profits? Need to keep 100LL available.

Scott Sherer

Thanks for the conversation fellows. Very interesting.