Citation X (C750)
Flight Crew Air Transport Pilot (ATP)
Human-Machine Interface
Aircraft Equipment Problem Critical
Aircraft
While I was preflighting the cockpit; the fueler advised me we were losing fuel [overboard]. I had told him that we were going to top off and he had already completed the float check. Fueling had already been stopped and clean up began. We were pulled out of and positioned away from the spill; two pools of fuel both approximately six feet in diameter. The aircraft had already stopped the fueling process and the fueler was putting away his equipment when the aircraft started to eject fuel. On the next leg the float check was completed again with no anomalies.
A CE-750 suffered a fuel spill following a 'top off' fueling.