Include

[jlrsn]

If you shake/swirl the Jet Fuel too much the water will be suspended in the fuel and it will take time for it to settle. That's why with Jet Fuel you don't sump your fuel tanks right after fueling as the water is still suspended in the fuel.

I always insist on sumping the truck myself before fueling. Also when refueling with Jet Fuel, unless single pointing, I also squirt the first quart from the nozzle to clean the garbage that has collected in the nozzle. I've had everything from pebbles, grass, to spiders come shooting out. I then, before putting the nozzle in the tank, wipe the nozzle as jet fuel picks up a lot of fine dust that washes off the nozzle which goes into the tank and mixes with any water which eventually creates a filter/engine fuel nozzle clogging slug. I've flamed out quite a few times in helicopters because of that with resultant autorotations.

With AvGas the water will settle right away and you sump the aircraft right after fueling.

The problem I've often found is that people use a little sump jar taking only a few ounces of fuel and on a lot of aircraft the water in the tanks will not enter the sample. With Jet Fuel, dependent on the aircraft, I always use a minimum of a quart of fuel per tank and on some aircraft I'll drain a gallon plus.

I've been refueling aircraft of all types and sizes all over the world for the last 50 years now and I've seen quite a few things happen.