shown in figure 7-12. The Fuels Maintenance Officer of each activity maintains a list of these officially des- ignated personnel. This list is updated at least quarterly. 2. During defueling operations, maintenance not directly required to facilitate the defueling operation is NOT to be performed. 3. Aircraft will be spotted 100 feet from all struc- tures and other aircraft. Grounding and tiedown pad- eyes must be available. In addition, at least one fire extinguisher must be available in the immediate vicinity of the operation. 4. Only defueled aviation turbine fuel can be re- issued to aircraft. All defueled AVGAS is downgraded and not used as aviation fuel. 5. Suspect aviation turbine fuel must be removed from the aircraft using a defueler only (not a refueler/de- fueler) and deposited in a designated holding tank. Ultimate disposition will depend on the results of later laboratory tests. Every effort should be made to reclaim off-specification fuel as JP-5, F-76 or fuel oil reclaimed (FOR). 6. All fuel removed from turbine engine aircraft is assumed to be a mixture of JP-4 and JP-5. Defueled turbine fuel must not be returned to JP-5 storage tanks without first confining the flash point of the fuel to be 140°F or higher. 7. Fuel containing leak-detection dye can be reis- sued to aircraft of the same squadron as long as the squadron’s requesting official signs a statement that the fuel is nonsuspect and is safe for use. NOTE Refuelers/defuelers may be used to defuel dyed fuel. However, this may present logistics problems since it may take several loads of fuel to flush the dye out of the refueler/defueler. The fuel may appear off-color when sampled prior to issue to another squadron’s aircraft. 8. The Fuels Maintenance Officer will personally decide the disposition of all defueled products. 9. The defueling unit is required to maintain a flooded suction above the anti-vortex splash plate in its tank to minimize turbulence and possible ingestion of air. Historically, a minimum of 1,000 gallons has been required in the defueling unit to resolve turbulence and air ingestion problems. Because of the wide variety of configurations of pump piping systems and tank sizes, 1,000 gallons of product mayor may not be enough. It is up to the local commands to determine the minimum amount by using manufacturers’ technical manuals and historical data. 10. The valve(s) that control the flow of fuel from the tank to the upstream side of the pump remain closed during defueling operations. This is to prevent the re- circulation of product in the tank. The valve(s) may be opened to prime the pump only when the pump is not operating. 11. If, during the defuel operation, the pump starts to lose prime or cavitates, the operation must be discon- tinued until the problem is resolved and the fuel super- visor authorizes a restart. At no time will a restart be authorized without waiting a minimum of 1 MINUTE to allow relaxation of any static charges. 12. At no time will defueler tank tops be opened during defueling operations. 13. Every aircraft defueling operation requires a minimum of three personnel: the defuel truck operator (supplied by the fuel division), a nozzle operator (sup- plied by the squadron), and a fire watch (supplied by the squadron). 14. A special log of each defueling operation is maintained. The following minimum information is contained in the log: a. Complete list of all squadron personnel authorized to sign defuel request forms. This list must be updated b. c. d. e. f. g. h. i. at least quarterly. All abnormal happenings. Aircraft buno number. Defueler number. Grade of product. Amount of product actually defueled. Scheduled amount to have been defueled. Disposition of product. Times when the defuel operation was started and completed. j. Names of the defueler operator and squad- ron personnel present during the defuel operation. 7-24