MD Helicopters MD900 with PW206E, Flight Manual

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CSP–900RFM206E–1
ROTORCRAFT FLIGHT MANUAL
MD900 With PW 206E
Systems Description
Original
7–27
To minimize structurally−transmitted acoustic noise from the transmission into
the passenger spaces, the transmission is supported from the mast base by eight
bolts in elastomeric bushings, and is restrained against rotation by a toothed
coupling arrangement that has a contoured elastomeric ring between the bottom
of the mast base and the top of the gearbox.
EXHAUST DUCT
INTERCONNECT DUCT
OIL COOLER
INLET DUCT
AIRFRAME
DECK
VIEW ROTATED
NOTAR FAN
DRIVE SHAFT
PRESSURE SWITCH
(LOW)
MAGNETIC
CHIP DETECTOR
F92–069–2
Figure 7–15. Drive System (Sheet 2 of 2)
Engine and transmission lubricating oil is cooled by air/oil heat exchangers
mounted in the sides of the cowling alongside the transmission. Each cooler is split
so that it serves separately one engine’s requirements plus half of the transmission’s
requirements. A direct drive fan on each side of the transmission induces ambient
air to flow through the cooler cores. Each engine has its own lubrication pump;
the transmission’s pump is located low on the front centerline of the gearbox.
Magnetic chip detectors are provided for each engine and the transmission. The
detector in the transmission has ‘‘burn−off ’’ capability; the detectors in the engines
do not.