Fuel draining is a drag when you're alone

[Effie Andree Wiltens]

[Kristin Winter]

[AlanBreen]

[Effie Andree Wiltens]

Hmmm... keeping stuff in the container might make them smelly though, or leave contaminants in the container that are indistinguishable from any that might be in the fuel, rendering the drainage process partially pointless. I wouldn't want the container to be too unwieldy for inspection.
I was thinking of something like this -- see attached picture.
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[AlanBreen]

Hello Effie,

We have never had a problem with smell. If you do the fuel drain before you do the rest of the preflight any residual left after the container has been emptied has evapourated.

We have never had a problem with any contamination in the container by storing items in it. At the worst there is some dust particles which are easily tipped out or brushed out with a cloth before doing the fuel drain.

One problem I see with your design is being able to see into the bottom of the container properly to be able to see any water/contamination which will be almost always on the bottom. The narrow neck will impede your view in my opinion. Water can be hard to see sometimes.

By happy coincidence our fuel bucket has "pockets" at the base of the bucket, this is where the contamination gathers. By tipping the bucket carefully the fuel will flow away from one pocket leaving the contamination behind making it very easy to see any contamination.

I have attached a diagram to illustrate.

Alan

[AlanBreen]

Hello Effie,

After looking at your picture again it seems that you might be using a glass jar to collect the fuel sample. That will make it easy to see any contaminants. If you were using glass had you considered that possibility of it getting broken or cracked.

Also how easy is it to get under the aircraft to fit the extension tube and then insert it into the jar? Are you intending the leave the tube there all the time?

One of the advantage of a large container, one with a wide opening, is that you don't need much of an extension tube and it can be left there permanently. We have very short plastic ones on our twin and it is quite easy to position the bucket under these without the risk of spillage. Our bucket is quite tall so the top of the bucket is within a few cm of the aircraft belly but a shorter bucket placed on a step or stool would work as well.

Alan

[Trevor Laundy]

[Effie Andree Wiltens]

[Trevor Laundy]

[Allen Taylor]

[Effie Andree Wiltens]

[AlanBreen]

[Effie Andree Wiltens]

Like you, I have six tanks, and I did wonder about people using a GATS jar. I had doubts about the bottle too, but thought it would be good for testing. 2-3 litres is a lot, it will be hard to find the right kind of container. We're still in a two-man operation acting as safety pilots for each other while we familiarize ourselves with the Comanche, so there is no urgent need for this gadget yet.

Something else cropped up that needs attention: apparently the 120 gallon capacity of our tanks is too big a temptation with fuel proces being what they are here. We’re dipstick-measuring our tanks before and after each flight and there are discrepancies that cannot be attributed to inattentiveness or venting. Fuel has gone missing while the aircraft was parked in the hangar. Not much, about 8-10 litres from tanks that have been used, so that without actual measuring it’s difficult to see. It's not incidental either. A previous time more than 60 liters evaporated, last weekend 27 liters. We’re compiling a record that we can use to start an investigation by airport security or the police. We’re totally pissed off that a member of our airport community should stoop so low to pilfer fuel – also unthinkable that it’s a fellow pilot/owner or a mechanic. Access to the airside of our airport is pretty near impossible for anyone else. It’s crazy that we’re now forced to install locks on our tank caps to protect ourselves from someone who's on the inside. If we can't trust one of them, who can we trust? I am so angry, sorry that this is developing into a rant, I'll stop now.

[AlanBreen]

Hello Effie,

Before you get too concerned about someone taking your fuel there are a couple of possible innocent explanations.

One is after you fill the tanks the fuel level can change as the fuel bladders can "settle' a bit after refueling making it look like the fuel level has dropped slightly.

The other thing that can happen (in the twins anyway) is for fuel to syphon from a tip to an aux tank if the solenoid valve selector isn't seating properly or from an aux tank to a main if the selector valve isn't seating properly. The tank receiving the fuel will overflow the fuel into the ground. The obvious indication is the loss of fuel in a tank.

Another likely indication that this is happening is when you remove the cap from the tank that is receiving the fuel, fuel will overflow out of the filler neck.

These are things to consider as reasons for your fuel discrepancies.

Alan

[Effie Andree Wiltens]

I hear what you're saying Alan, but...

(a) could the loss really amount to as much as we have measured within the time of one week?

(b) Fuel also disappeard from the aux tanks.

(c) This was long after tanks are supposed to have settled. More than a week after topping up, with several trips in between.

(d) if fuel transferred from one tank to another, the total would still come out close to whatever was measured before. The difference could surely not be as much as 27 liters (more than 7 gallons)?

(e) A rumour is circulating that the culprit might be the guy with the tow vehicle. We are not the only ones with evaporation problems, it seems. He might be taking a little here and a little there, careful to keep the quantities low so that no one can be completely sure and it's difficult to prove.