FUEL METERS Temperature-compensated meters should be in- stalled at point of custody transfer. Meters used for services such as fueling of aircraft, motor vehicles, and boats or loading of tank trucks or tank cars are positive displacement meters. Turbine meters may be used for larger volume steady transfers such as load- ing of ships, barges, or pipeline transfers. FUEL PRESSURE GAGES Pressure gages must be easy to read and accurate within 1 psi, with graduations in 1-psi units. SAMPLING CONNECTIONS All sampling connections are the flush-type, dry- break, quick-disconnect (Gammon fittings) with dust caps. Fuel-sampling and pressure-testing connections are installed at the following locations: Receiving points Tank outlets Inlet and outlet sides of filter/separators and fuel monitors Refueling nozzles Each side of a block valve, so that the fuel remaining in each portion of a fuel transfer pipeline can be sampled. HOSES All hoses used for aviation fuel service at shore activities should be semihard-wall, noncollapsible hose. The diameter of the hose must be compatible with the desired delivery rate to the aircraft. Unless otherwise specified, aircraft delivery hose on refueler trucks must be a minimum of 50 feet long. Shore-base hoses contain no electrical bond or bonding wire through the center of the hose. Where two hose assemblies are attached to the same outlet or source of fuel, each hose assembly must have its own shutoff valve in the piping upstream of the hose. EMERGENCY DRY-BREAKAWAY COUPLING An emergency dry-breakaway coupling should be installed on the refueling hose at or near the place where the hose attaches to refueling equipment piping or the hose reel. This device is required for each direct refueling system pantograph and is recommended for all other installations. DRY-BREAK QUICK- DISCONNECT COUPLING A dry-break quick-disconnect coupling is in- stalled at the nozzle end of the hose and has a 60- or 100-mesh screen that is readily accessible without the use of tools. HOSE END PRESSURE REGULATOR The single point pressure refueling nozzle assem- bly includes a hose end pressure regulator set for a maximum of 55 psi. AIRCRAFT REFUELING NOZZLES The pressure refueling nozzles used for shore re- fueling are the same as for afloat refueling. The typi- cal nozzle is the Carter D-1 or MD-1. The overwing (gravity) nozzles used for shore refueling are also the same as used for afloat refuel- ing. See chapter 5 for details on both types of nozzles. AIRCRAFT REFUELER TRUCK FILL STANDS The loading rack has a separate loading system for each grade of product to be handled. The equip- ment required at a truck fill stand for aviation fuel is as follows: SPR (pressure) nozzle with dry-break quick-dis- connect and strainer. Loading hose approximately 10 feet long or me- chanical loading arm with nonlubricated swivels. Loading-hose fuel-thermal-pressure relief valve. Diaphragm-operated two-stage control valve (low flow/high flow) with adjustable time delay to pre- vent the high-flow pilot from opening until 1 min- ute after start of fuel flow. Meter with rated capacity equal to the maxium flow rate of the loading station. Temperature-compen- sating positive displacement meters are recom- mended. 7-4