How long can fuel be safely stored?

Ben Visser is an aviation fuels and lubricants expert who spent 33 years with Shell Oil. He has been a private pilot since 1985.

Reader Jerry Johnson recently wrote in with a question about fuel storage: “Rotax indicates that octane ratings degrade rapidly and significantly with storage. If so, wouldn’t storage for a matter of weeks render the fuel dangerous to use in aircraft?”

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Testing for ethanol

Ben Visser is an aviation fuels and lubricants expert who spent 33 years with Shell Oil. He has been a private pilot since 1985.

How do you test for ethanol in auto gas?

Recently, I’ve received a lot of e-mails from people who want to know exactly how much the water phase volume will change in the test, and whether they can mix water with the bulk fuel and remove the ethanol to make the auto gas safe for their aircraft.

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The fuel of the future: Is it already here?

Ben Visser is an aviation fuels and lubricants expert who spent 33 years with Shell Oil. He has been a private pilot since 1985.

I recently received a note from reader Scott Shroyer, who is looking to buy a used Cessna 182 with an auto gas STC. He wants to know if it is worth his time to buy the 182 “in hopes of finding auto gas at an airport to fill it up?”

A lot depends on which state Scott lives in as to the availability of auto gas without ethanol. I then forwarded his question to Todd Petersen of Petersen Aviation, who has sold more than 34,000 mogas STCs worldwide since 1983.

Scott’s question raised several questions in my mind. First, is it worth considering the fuel requirement of an engine in the purchase of an aircraft? I would say that it does at this time.

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Ethanol: A very real danger

Ben Visser is an aviation fuels and lubricants expert who spent 33 years with Shell Oil.

In a recent post I discussed the problems with ethanol and water in a plane’s fuel system. I received a large number of replies and most were very positive. However, I did get a number of negative notes. For example, one reader wrote: “Ben Visser, go argue with your wife to get your stupid little victory! I’ve been using ethanol mogas for over 20 years without a drop of water showing up…You’d make a great corrupt politician.”

Two problems here: First is that this guy is definitely not married, because if he were he would know that you never win an argument with your wife. You only think you are ahead sometimes, but you never truly win. The other problem is poor logic. [Read more…]

Unraveling the mysteries of fuel

Ben Visser is an aviation fuels and lubricants expert who spent 33 years with Shell Oil. He has been a private pilot since 1985.

Fuel is an item that is very important for the proper operation of our aircraft. Even though the world is full of “fuel experts,” it is still a bit of a mystery.

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How to prepare for the end of 100LL

How should aircraft owners prepare for the switchover from 100LL to its replacement? In a previous post, I stated that if — or when — 100LL goes away, the only fuel that will be universally available for general aviation will be one that is chemically very similar to 100LL, but without the lead, and an octane rating of around 94.

If you have a low compression ratio engine qualified on 80/87 or mid-90 octane fuels, you really do not need to change anything. The only concern is that when the engine is overhauled and broken in on straight unleaded fuel, there maybe a problem with exhaust valve recession. If I owned one of these aircraft, I would wait until 100LL is about to go away and then buy a barrel. [Read more…]