Sincere apologies for incorrect use of the word mix. Distribute/disperse would have been better.My point is that the water settles at the bottom of the tank shaking the wing would disperse it around the tank and your drain might not show any significant water.
I don’t mean shake the wings as vigorously as you would a salad bottle containing oil and vinegar, which can indeed intermingle two ingredients that normally separate into distinct layers very quickly.
Just rock it gently. I was told that if a tank is not fully fueled, i.e., not up to the cap, water droplets can condense/form on the inside of the tank, and that gently rocking it can dislodge them and make them sink to the drainage point.
I was told to do this before draining the tanks because if there is water condensed inside the tanks, and you don’t get rid of it, it could come back to haunt you when the run up and take off dislodges it, and it then get into the fuel line to the engine, which does not burn water as efficiently as fuel.
Distinguishing between pale blue fuel and water is easy enough in broad daylight, but it might be more difficult at night. I was also taught to drain it twice if there was a significant amount of water.
[Am I the only one who was taught this?]
That’s all I ws trying to say.