CSP
−
902RFM207E
−
1
ROTORCRAFT FLIGHT MANUAL
MD900 (902 Configuration with PW 207E)
Systems Description
Original
7
−
30
Reissue 2
that are associated with the EEC's are protected in a similar manner. With this
protection in place, freedom from lightning damage is also assured.
Train Mode:
Placing an engine control switch in the TRAIN position will simulate a one engine
inoperative condition by resetting the selected engine's governed speed to 92
percent N
P
, thereby putting the engine on standby while allowing single engine
training on the opposite engine. In the event of an engine failure on the opposite
engine, the engine in TRAIN will automatically revert to 100% N
P
.
Additionally, the opposite engine will retain the 5 minute Take-off Power engine
parameter limiters. The result is more realistic pilot OEI training, providing
rotor droop in training if the power requested is above the limiters as would
happen in a real OEI condition.
Emergency Manual Control:
The controls for manual operation of the engine power consist of two twist grips
on the collective pitch stick and a push button located on the collective control module
at the end of the collective stick.
The EEC is designed to ``fail-fixed” (EEC's stepper motor is fixed at its last con
trolled power setting) so there is no sudden change in the level of power if an
EEC becomes inoperative. The only noticeable happening is illumination of the
yellow EEC/red FAIL
warning on the Integrated Instrument Display System
(IIDS). No matter at what power level the EEC becomes inoperative, there is
sufficient travel in the twist grip to control the engine manually from full power
to idle and engine shutdown.
After the EEC becomes inoperative, the pilot uses the appropriate twist grip
on the collective stick to modulate the power.
Summary of Contents for MD900 Explorer
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