Avtrician,
The RAF refuellers had one bonding reel to attach to the a/c, a bonding plug and a crocodile clip at the hose end (pressure or open line) to plug in/clip on at the fuelling point. We stopped attaching the spiral wound wire within the hose to the hose end filler some years ago, it was said that the fuel within the hose made a bond. The vehicle also had an earth strip, usually at the rear connected to the chassis and trailing on the ground, conductive tyres were also fitted. An electrician was to check all these connections with a safety ohmmeter weekly and sign the vehicle docs as to their integrity.
PM