I was a machinist in a previous life, worked on automatic screw machines (Easy Boys) called Carlton Screw machine Products (Easy Boys), located on Bush Lake Road (Easy Boys). I was told a story about an insurance sales droid mentioning that building/content insurance would be cheaper (easy boys) if the building was sprinklered (easy boys). Owner relayed a story about a machine shop (easy boys) that did have sprinklers... Fire started, sprinklers went off, building (easy boys) burned to the ground. Back in the day (easy boys), oil was used as a coolant and cutting fluid. Like 100 gallons in an open sump. Do the math (easy boys).
Static discharge when fueling is a real issue, though pretty well mitigated now. Tires are (were) the insulator, they now have carbon black (a modest conductor) in them. The fuel hoses (easy boys) have a metal spiral insert that does double/triple duty. This is all well and good for dissipating static charges prior to fueling.
But think about this. The motion of fuel through a hose generates a static charge. Not a big deal (mostly), as the hose is grounded, so is the car/motorcycle. But what about the air gap between the falling fuel and the metal tank? *Even if* the tank is grounded.
I bring this up as some of you know I'm building a plane. A fiberglass plane, with fiberglass fuel tanks in fiberglass wings. Fiberglass is an insulator, so is fuel. Pumping fuel into the tanks generates a static charge. How do I ground my air frame?
Rick (Easy boys)
If your plane is a kit, there should be instructions regarding that placement of grounding/bonding straps where needed. If not, suggest contacting the EAA is some fashion, there are a lot of people in that organization with knowledge that far exceeds what you'll find here. The FAA may have some guidelines, but I think even they lag behind what you might find at the EAA. Most of what I worked on in general aviation was aluminum structure, typical factory-built stuff (except for the wood/fabric dinosaurs). The last company I worked for was just starting to get some fiberglass/carbon fiber aircraft for their flight school when I left the game, so I never really worked on them much. Fiberglass/composite cowlings, fairings, wingtips, etc., normally have some sort of bonding strap that will conduct away lightning so as to prevent the otherwise high resistance from stating a fire, and to help conduct away also the static charges that occur just by moving rapidly through the air. Many airplanes, even down to small Cessnas and Pipers, etc,. have static wicks mounted on the wings, stabilizers, and control surfaces to help discharge it in flight. Bigger ones have bigger and more numerous wicks. A big aircraft like commercial airliners can build up humongous static charges that could literally blow a hole in the structure and fry a lot of electronics if allowed to build up until it sparked off. It needs to bleed away slowly, which is what the static wicks do. Metal fuel lines are normally bonded/grounded to the metal structure with small ground wires, even in metal airplanes, again, for lightning protection.