Geico266
Well Known Member
Auto Gas -v- Avgas
I would like to start a thread dedicated to water "contamination" in fuel. There seems to be an under current of discontent and arguing about mogas & airplanes. I would like to bring out the best minds and pilots here and get some real world experience with guys using Mogas in aircraft.
There are more aircraft flying on mogas than any other fuel. Rotax has more engines in the air at any one time than any other piston engine in the world. The fuel of choice for the 912 / 914 is unleaded 92 O.
I'm no expert, but to say that mogas is dangerous seems to be a stretch.
Having said that I personnaly have experenced water seperation in my 100 gallon trailer tank I tow to the airport. I mix the fuel 50/50 ( prem. car gas & 100LL). This occurs when the temperature drops and a small amount of water seperates from the fuel and settles in the bottom of the tank. It is red in color and tells me (and the fuel supply people) that it is coming from the local pipe and distribution tank farm. I sump that tank and it's taken care of. I also, tip the tank when pumping to ensure no seperated water gets into the airplane.
According to "the experts" (See links below) any gasoline can hold water. Most of the water is burned up and no harm is caused. Water can seperate at a rate of .5 tsp per gallon (no alcohol in the fuel) when the temperature changes water can seperate out and you could have a potential of 9 teaspoons of water (under worst case senerio) in your tanks.
Water phase separation (nice read):
http://www.epa.gov/OMS/regs/fuels/rfg/waterphs.pdf
If you sump your tanks before and after each flight you should get a reading on what (if any) water is present in the fuel.
Lets keep it civil, informative, and factual.
I would like to start a thread dedicated to water "contamination" in fuel. There seems to be an under current of discontent and arguing about mogas & airplanes. I would like to bring out the best minds and pilots here and get some real world experience with guys using Mogas in aircraft.
There are more aircraft flying on mogas than any other fuel. Rotax has more engines in the air at any one time than any other piston engine in the world. The fuel of choice for the 912 / 914 is unleaded 92 O.
I'm no expert, but to say that mogas is dangerous seems to be a stretch.
Having said that I personnaly have experenced water seperation in my 100 gallon trailer tank I tow to the airport. I mix the fuel 50/50 ( prem. car gas & 100LL). This occurs when the temperature drops and a small amount of water seperates from the fuel and settles in the bottom of the tank. It is red in color and tells me (and the fuel supply people) that it is coming from the local pipe and distribution tank farm. I sump that tank and it's taken care of. I also, tip the tank when pumping to ensure no seperated water gets into the airplane.
According to "the experts" (See links below) any gasoline can hold water. Most of the water is burned up and no harm is caused. Water can seperate at a rate of .5 tsp per gallon (no alcohol in the fuel) when the temperature changes water can seperate out and you could have a potential of 9 teaspoons of water (under worst case senerio) in your tanks.
Water phase separation (nice read):
http://www.epa.gov/OMS/regs/fuels/rfg/waterphs.pdf
If you sump your tanks before and after each flight you should get a reading on what (if any) water is present in the fuel.
Lets keep it civil, informative, and factual.
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