Last week in this post I asked…
Before you pulled the helicopter out of the hanger this morning, you checked the sumps and it looked good. It’s 10 degrees C outside and snowed last night, so you’re happy this will be a quick refuel–just 3 gallons. You drive the fuel truck from the tank out to the ramp, pick up the nozzle, pop it in the tank, and get your fuel. You know the truck is topped off every night, and you’ve never had debris or water come out of this tank. So, is there a good reason to check the sumps again?
This is something I actually encountered, and the issue isn’t the risk of condensation, but introduction of snow from the fuel nozzle. The fuel truck sat outside overnight and was covered with a good bit of snow. The fuel nozzle just sits exposed and laying flat on the side of the truck. As students would fill their tanks, they’d lay the nozzle back down on the bed of the truck, where it could get packed with snow. The next guy in line, if he didn’t check the nozzle, would get a snowball blown into the tank. Once the snow melted, it’d end up at the bottom of the tank. Most students don’t check the tanks after fueling, in part because it’s a reliable source, and because there’s a bit of competition for the fuel truck (which has the waste container strapped to it). Fortunately, nobody ended up with much water in their tanks before somebody noticed what was going on.