Witbank,South Africa,c2001: During a normal day’s flying our C205A,someone assisted me with a refuel. I ,stupidly,neglected to check the fuel caps. All was normal on the climb to 9000ft,dispached the load and started the descent where upon fuel started to flow into the cabin through my door and window and through the airvent,soaking the dash and me. I was supposed to call FAJS approach by now,decided not to touch anything at all! After a flap-less landing,I pulled the big red knob and walked away. Left everything switched on until,maybe an hour later,I returned in fresh attire to kill all the electrics! Had to make a call to FAJS to explain my silence!
Many operations do use “fuelers”. But they MUST be fully checked out on how to safely do it. From the sounds of the description here it may not have been a regular occurrence having someone else fuel the aircraft.
I once had something similar happen after a fueling in a Twin Otter. Jet-A was streaming out of the aft tank fueler port. Fortunately at a safe altitude a jumper was actually able to reach the cap and stow it. A long debrief and refueling followed.