Draining the fuel tanks is one of the first things we are taught to do in the pre-flight routine. Essentially there are a few things we are looking at when draining the fuel:
Colour – Does the fuel colour match the correct fuel type for the aircraft? For example Avgas should be blue in colour.

Smell – Do the contents of your fuel drainer smell like fuel, and the correct type of fuel?

Contaminants – Can you see sediments or deposits of any kind?

Water – Water is heavier than fuel, so you will notice that it sinks to the bottom and will be clear in colour.

My focus of this article is what to do if you find water in your fuel draining gadget during your pre-flight?

You may firstly be wondering how on earth water gets into the tanks in the first place, and there are a number of culprits:
Rain (some aircraft fuel caps do not seal as well as we would like them to)
Fuel from stations or tanks contain water and this is pumped into the aircraft tanks.

So what should you do?
Always check your fuel! Do not assume that the aircraft that you are flying has a fuel drainer on board – much like Bic black pens they always seem to grow legs, so please keep one in your flight bag. I have seen frustrated pilots searching high and low for this valuable tool, but whatever you do, do not miss out on this important step.

If the first fuel sample reveals water, take a second sample, if this sample also contains water, then this is cause for concern. There is common thinking that if you keep draining with your little gadget until there is no more water then you should be ready to go? The key here is knowing your aircraft’s fuel system. If you are finding water multiple times, this is not a good sign! Even if it does eventually come up clear in your fuel gadget, this does not mean that the whole system is clear of water, some water may still be hiding in the fuel lines, and as we all know aircraft engines do not burn water, so watch out!

What would I do? Definitely understand the fuel system of the aircraft you are flying – not always easy, especially if you are not very technical, but it will help you understand where the fuel is going and the implications. If I spot water several times before it appears clear, I would probably call the AMO…

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