air-moisture contaminant remover. When the
missile cooling loop is not required, the fairing
is removed from the aircraft. The ultimate heat
sink is ram air and/or refrigeration system air for
cooling; hot air from the bleed manifold 400°F
temperature control system provides heating. The
WCS/missile temperature control system also uses
cooling air from the ground cooling system when
ground operation is required.
Setting the liquid cooling switch to the
AWG-9/AIM-54 position starts the missile
coolant pump motor. The pump circulates 18
gallons of coolant per minute through the
missile air-moisture-contaminant remover, heat
exchanger, weapon rails, left and right pylons,
launchers, and as many as six Phoenix missiles.
The heat absorbed by the coolant from the
missiles is removed in the air-to-coolant heat
exchanger. When the loop is operating in the
cooling mode, the missile inlet coolant
temperature sensor controls the fluid temperature
at 70°± 3°F by opening or closing the cold air
modulating valve. The valve varies the amount
of cold air flowing from the refrigeration system
through the missile heat exchanger.
When the temperature of the coolant fluid
returning from the missile is below 40°±3°F, as
sensed by the missile outlet coolant temperature
sensor, the cooling system automatically switches
to the warm-up mode. In this mode, the cold air
modulating valve closes and the hot air
Figure 1-18.Missile cooling system.