Hi, yep I'm aware of that, just giving the worse scenario,long range e.g. 2 hrs from nearest airfield, pump running (will not shut off via OHP) in empty vapour filled tank... does anyone know if there is an overheat protection where the pump will close due heat expansion etc to prevent a possible explosion or in those extreme circumstances would engineering allow a dispensation for you to pull a CB to ensure pump cut off, thanks, pudd