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Jim Lee

fuel drains

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Jim Lee

Hi all,

I will be receiving my Phoenix in a few month and was wondering why there isn't a quick fuel drain at each of the lowest point of the two fuel tanks. Have any of you encountered issues of water contamination? I understand that there is a filter for debris before the fuel enters the engine. Have any of you thought about replacing the existing fuel drain with the quick drain option?

George Feldman

Hi George,

There is a quick drain at the low point of each wing. You unscrew the drain, and the fuel pours out. It works great because if you want to drain all of the fuel from the wings, you unscrew the drain and let the fuel pour into a funnel into a gas can while you go off and do other work.

There is a filter at the fuel pick up inside the fuel tank. There is both a gascolator and a fuel filter on the firewall.

If you run the engine at 5000rpm until the tank runs dry, the engine will typically run about 10 minutes after the Dynon fuel gauge reads zero. Then after you land, you can drain about half a cup of fuel out of the tanks. So the drain is located at the low point of the wing tanks, and almost all of the fuel in the plane is usable.

I have never found any water in any of the Phoenix in my care. I check for water only occasionally, and should probably do it more often after Jeff's story below. Especially if I will be flying in wave.


I live in the east. When I owned a hangared SLSA Lambada, I hadn't checked for water in the 100LL fuel for around 300 hours. I flew to 15k in wave in February, with the engine idling. The gascolator had picked up some water at the last top up, and that froze and I had to land and disassemble the gascolator before I could get sufficient power for a takeoff. Not fun in freezing 30kt winds. Now I am pretty good about checking for water. And I very very rarely find any.


No water after 350 hrs and checked before every flight. Unscrewing the drain allows full drainage. I have replaced the seal for one drain for leaking. Very easy to do if the need arises.


You are allowed to use octanes as low as 91 AKI, which is all I can find in our area.

My experience with water in fuel tanks is zero water so far.

· That includes 20 years of flying my ASH 26 E self-launching sailplane (maybe as much as 700 gallons of fuel). It's not just me, but asking on our 26 E group, with about 150 owners around the world, no one reported ever finding water in the tank.

· My Phoenix has 225 engine hours using 100LL and non-ethanol Mogas, and I've never found water in the fuel.

· I'm guessing there are several reasons:

o the fuel rarely/never has water in it, so the water must come from somewhere else

o the 26 E/Phoenix and it's tanks fiberglass/carbon fiber, not as prone to producing condensation as metal airplanes

o most of the 26 E's are kept in trailers, and Phoenix are mostly in hangars, so external water entering it is very unlikely.

o Many are in dry, low humidity areas (as both of mine are)

I typically check for water whenever I add a new batch of fuel, but not before every flight, unless it's been out in the rain. I'm not suggesting this is a wise practice, however.


There is a fuel drain for each tank. Unscrew the drain a few turns with a standard fuel drain tap. Def use nonethanol 93 octane Mogas. Water will periodically show up in any fuel, especially those with no ethanol to absorb water. Water condenses out of the air drawn into the tank. Must keep that drained off or it could freeze in the filter or gascolator. Don't ask how I know.


Hi George,

I have never found any water in my fuel tanks. I do, however use only ethanol free fuel except in the rare trip when it is not available.

Art Daun

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