As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
RIGHT MAIN FUEL TANK LOST 400LBS OF INDICATED FUEL IN APPROXIMATELY 15-20 SECONDS. ONLY APU WAS IN OPERATION AT THE TIME. ACFT GROUNDED. IAW FIM 28-41-00-810-814. COMPLIED WITH INITIAL EVALUATION. CURRENT STATUS NO FAULTS. GROUND TEST PASS. SUMPED APPROXIMATELY 10 GALLONS OF FUEL FROM RT TANK. NO CONTAMINATION NOTED.