Controls
TACHOMETER FAILURE (POH 3-7)
If rotor or engine tach malfunctions in flight, use remaining
tach to monitor RPM. If it is not clear which tach is
malfunctioning or if both tachs malfunction, allow governor
to control RPM and land as soon as practical.
NOTE
Each tach, the governor, and the low RPM
horn are on separate power circuits. A special
circuit allows the battery to supply power
to the tachs with the battery and alternator
switches both off.
DUAL TACHOMETER (POH 7-22)
An electronic engine and rotor dual tachometer is standard. Engine tachometer signal is provided by magneto breaker points. Rotor tachometer signal is provided by two magnetic senders at the main gearbox drive yoke. Each tachometer is on a separate circuit with its own circuit breaker. With battery and alternator switches off, the tachometers continue to receive power from the battery through a bypass circuit as long as the clutch actuator switch is in the engage position.
NOTE
Do not stow helicopter with clutch switch engaged. The tachometers are powered with the clutch engaged and will discharge the battery.
WARNING: ALWAYS CHECK POH FOR THE MOST UP TO DATE INFORMATION!
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