Heat / Defog Control Cable; Heat / Defog Ejector; Plenum Heat / Defog Hoses; Defog Manifolds - MD Helicopters MD Explorer Servicing And Maintenance

CSP−900RMM−2
distribution to the defog manifold and foot
heater valves.
H. Heat / Defog Control Cable
The heat/defog control cable is a push pull
cable constructed of stainless steel. The cable
is located on the center console. The cable
adjusts the heat/defog valve that controls
bleed air flow entering into the heat/defog
ejector for distribution to the defog manifold
and foot heater valves.
I. Heat / Defog Ejector
The heat/defog ejector is located below the
crew compartment floor near the aircraft
centerline. The ejector acts like a flow divider
mixing inside ambient air with hot engine
bleed air to produce heated crew/defog air.
J. Plenum Heat / Defog Hoses
The plenum heat/defog hoses are flexible
silicon rubber coated woven fiberglass hose
with a nylon helical reinforcement. Located in
the lower left and right cockpit fuselage
section, the hoses route bleed air from the
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Revision 13
MD Helicopters, Inc.
Rotorcraft Maintenance Manual
21-40-00
heat/defog ejector to the heat/defog manifolds
and foot heaters.
K. Defog Manifolds
The defog manifolds are located below the
cockpit wind screens. The defog manifolds are
constructed of composite material. The defog
manifold allows heated air to blow against the
pilot and copilot wind screens for defog
purposes.
L. Foot Heater Control Cable
The foot heater control cables are push pull
stainless steel cables. The two control cables
are located under the instrument panel. Each
foot heater control cable operates a butterfly
valve, which allows the pilot/copilot to adjust
heated air outflow.
M. Foot Heater Valves
The foot heater valves are mounted on the side
of the forward battery compartment, directed
towards the pilots feet. The foot heater valves
are constructed of composite material with an
internal aluminum butterfly disc. The foot
heater valve allows for a varying amount of
heated air to blow onto the pilot/copilot feet.