environmental laws. You must also ensure that during and after PMCS are done and that DA Form 2404 or
DA Form 5988-E (Equipment Inspection Maintenance Worksheet) is annotated with any faults or deficiencies
found. The completed DA Form 2404 or DA Form 5988-E is returned to the motor pool with the equipment.
PART F - SAFETY
Switch Fueling. Switch fueling means supplying an aircraft with fuel that has flammability characteristics
different from that which is already in the tank. The flammability characteristics of the mixed fuel will be
different from the two fuels involved. The danger is that if a spark should occur in the tank, the vapor-air
mixture above the fuel may be in the flammable range and an explosion could result. If an aircraft is to be
switch fueled, the rate of flow at the nozzle should not exceed 50 percent of the rated flow. Changing to JP-4
after using a kerosene-grade fuel also constitutes switch fueling.
Heat. Aircraft, vehicles, and engine-powered equipment generate heat by burning fuel. They also generate
static electricity because of friction between moving parts. The engine heat of an idling aircraft turbine
engine is in the auto-ignition range of JP-4. Poorly maintained vehicle engines may backfire or discharge
sparks. Do not allow any work to be done on an aircraft's batteries while the aircraft is being refueled.
Aircraft radios may operate to receive messages during refueling, but radio transmissions from the aircraft
are not allowed because of the danger from arcing. Do not use flashlights within 50 feet of the refueling
operation unless they are approved explosion-proof type. Do not allow electric handtools to be used in the
refueling area. The electric circuits of tools used in refueling operations must be maintained in top condition
to prevent short circuits around defects. And in addition, the beam of high-frequency radar equipment can
ignite a flammable vapor-air mixture.
Open Flame. The danger of an open flame is that it will ignite fuel or a flammable vapor-air mixture. Do
not allow any type of open flame, or any flame-producing device within 50 feet of an aircraft refueling
operation.
Static Electricity. There are two ways to prevent static electricity from sparking. The charges on
different materials can be equalized by connecting them with a conductor (bonding). Also, a way can be
provided for the charges to dissipate harmlessly (grounding). The Army uses both of these methods to
control static electricity.
Bonding is the process through which two conductive objects are connected to lessen their potential
differences. Bonding does not dissipate the static electricity. It equalizes the charges on two unlike objects
(an aircraft and a refueling nozzle) in order to preclude arcing as the two objects are joined. A nozzle-to-
aircraft bond is required. This bond is made before the nozzle dust cap or fuel tank cap is removed.
Likewise, do not disconnect the bond until refueling is complete and the fuel tank cap and nozzle dust cap
are replaced.
Grounding is the process that provides a conductive path into the ground so that a static charge is not
trapped on the surface of the equipment where it can discharge as a spark. This conductive path is made by
connecting a conductive cable from the piece of equipment to a conductive metal rod that is driven into the
earth to reach the level of permanent moisture. Common sources of static electricity are identified as
follows:
Vehicles.
Human body.
Lightning.
Air Traffic Control. Air traffic control (ATC) is required for safe refueling operations. An air traffic
controller or some other adequately trained person is required at each refueling point that serves more than
one aircraft. This person controls and directs refueling traffic and resupply aircraft. He provides flight
personnel with information such as wind direction and velocity, remaining fuel supply, enemy activity in the
immediate area, hazards or obstructions to landing, and emergency situations. At a fixed airfield, full radio
communication equipment is provided for controlling air traffic. At a large semipermanent or temporary
refueling point a radio control tower should be used whenever aircraft are being refueled. In forward areas,
personnel controlling air traffic should have an FM radio suitable for ground-to-air or ground-to-ground
communication. Aircraft marshaling signals and landing aids are necessary at semipermanent and forward
5-5
QM 5095
Previous Page
