MD Helicopters 369-500, Maintenance Instructions Manual

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CSP-HMI-3
MD Helicopters, Inc
.
MAINTENANCE MANUAL
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Revision 7
95-30-00
The information disclosed herein is proprietary to MD Helicopters, Inc.
Neither this document nor any part hereof may be reproduced or transferred to
other documents or used or disclosed to others for manufacturing or any other
purpose except as specifically authorized in writing by MD Helicopters, Inc.
Copyright
©
1999 − 2016 by MD Helicopters, Inc.
increased or decreased, it produces an imbal­
ance of the strain gauge bridge. The bridge
imbalance creates an output signal proportion­
al to diaphragm pressure to drive the indica­
tor. The system receives 28 Vdc power from
the INSTR circuit breaker on the circuit
breaker panel. The indicator is an internal
lighted instrument. The four digital LEDs
provide the exact current shaft horse power
reading. Corrections occur two times per
second.
8. Analog Indicator − Torque, TOT (600N)
The dual analog module is a precision micro
processor based instrument for displaying
engine parameters. This module consists of
two completely independent analog indicators.
The front of the analog module contains two
parallax free pointers, two front-accessible
buttons and four LEDs and is backlit for both
day and night operation. Each indicator
displays its respective engine parameter
reading on the analog dial as well as
transmitting digital data on the data bus to
the Torque/TOT quad digital indicator. The
quad digital indicator displays the analog's
output digitally on the upper half of both
LCDs. The LEDs are used for indicator status,
while the buttons provide a user interface.
9. Quad Digital Indicator − Torque, TOT, OAT,
N
1
(600N)
The quad digital indicator contains two LCDs,
one in each window, with two lines for
numerical display, with legends adjacent to
each display. The quad digital indicator is
capable of posting four parameters at one
time. Torque and TOT are posted on the upper
half of the LCD with the lower half of the
display dedicated to the OAT and N
1
indicators. There is a red warning LED for the
N
1
indicator located to the right of the N
1
display. The LCDs are backlit for both day and
night operation. Two front buttons are
provided to select and/or control exceedance
review functions.
10. Oil Pressure Indicating System
(369D/E/FF − 500N)
(Ref. Figure 404) The direct-reading (wet)
engine oil pressure indicating system is
equipped with a 0 - 150 psi gauge. A 1/8 inch
diameter corrosion resistant steel tube
connected to a snubber assembly on the front
of the engine gear case transmits engine oil
pressure impulses forward to a firewall
mounted bulkhead union. Tubing between the
firewall and gauge is 1/8 inch diameter nylon.
Engine oil pressure tubing is routed next to
the torque gauge tubing from the firewall to
the instrument panel.
11. Engine Oil Temperature − Oil Pressure
Indicator (600N)
The engine oil temperature - oil pressure
indicators are two instruments in one indica­
tor. The oil temperature is displayed in degrees
Celsius and the pressure in pounds per square
inch. The temperature pointer is driven by
electrical signals produced by a resistance
bulb-type temperature sensor. The oil
pressure pointer is driven by a pressure
diaphragm and a stain gauge bridge-type
pressure transducer. The indicator receives 28
Vdc electrical power input from the INSTR
circuit breaker located on the circuit breaker
panel. The indicator is an internally lighted
instrument.
12. Quad Digital Indicator − Oil Temp, Oil
Press, VDC, AMP (600N)
The quad digital indicator contains two LCDs,
one in each window, with two lines for
numerical display, with legends adjacent to
each. The display is capable of posting four
parameters at one time. The LCDs are backlit
for both day and night operation.
13. Engine Torque Indicating System
(369D/E/FF − 500N)
(Ref. Figure 404) The engine torque gauge
indicates engine torque supplied to the engine
output shaft. The torque gauge is a direct-
reading instrument with a pounds-per-squa­
re-inch indication equivalent to the amount of
torque exerted on the accessory gear train by
the turbine output shaft. Oil pressure is routed