Commercial ACS Standards — Helicopter

11. Warning and Caution Lights

WARNING/CAUTION LIGHTS
NOTE
If a light causes excessive glare at night,
bulb may be unscrewed or circuit breaker
pulled to eliminate glare during landing.
OIL
MR TEMP
MR CHIP
TR CHIP
Indicates loss of engine power or oil pressure.
Check engine tach for power loss. Check oil
pressure gage and, if pressure loss is
confirmed, land immediately. Continued
operation without oil pressure will cause
serious engine damage and engine failure may
occur.
Indicates excessive temperature of main rotor
gearbox. See note below.
Indicates metallic particles in main rotor
gearbox. See note below.
Indicates metallic particles in tail rotor gearbox.
See note below.
NOTE
If light is accompanied by any indication
of a problem such as noise, vibration, or
temperature rise, land immediately. If
there is no other indication of a problem,
land as soon as practical.
Break-in fuzz will occasionally activate
chip lights. If no metal chips or slivers
are found on detector plug, clean and
reinstall (tail rotor gearbox must be
refilled with new oil). Hover for at least
30 minutes. !f chip light comes on again,
replace gearbox before further flight.
WARNING/CAUTION LIGHTS (cont’d)
LOW Indicates approximately one gallon of usable
FUEL fuel remaining for all-aluminum fuel tanks or 1.5
gallons for bladder-style tanks. The engine will
run out of fuel after approximately five minutes
at cruise power for aircraft with all-aluminum
tanks or ten minutes with bladder-style tanks.
CAUTION
Do not use low fuel caution light as
a working indication of fuel quantity.
CLUTCH Indicates clutch actuator circuit is on, either
engaging or disengaging clutch. When switch
is in the ENGAGE position, light stays on until
belts are properly tensioned. Never take off
before light goes out.
NOTE
Clutch light may come on momentarily
during run-up or during flight to
retension belts as they warm-up and
stretch slightly. This is normal. If,
however, the light flickers or comes
on in flight and does not go out within
10 seconds, pull CLUTCH circuit
breaker and land as soon as practical.
Reduce power and land immediately
if there are other indications of drive
system failure (be prepared to enter
autorotation). Inspect drive system
for a possible malfunction.
ALT Indicates low voltage and possible alternator
failure. Turn off nonessential electrical equipment
and switch ALT off and back on after one
second to reset overvoltage relay. If light stays
on, land as soon as practical. Continued flight
without functioning alternator can result in loss of
electronic tachometer, producing a hazardous flight
condition.
WARNING/CAUTION LIGHTS (cont’d)
BRAKE Indicates rotor brake is engaged. Release
immediately in flight or before starting
engine.
STARTER-ON Indicates starter motor is engaged. If light
does not go out when ignition switch is
released from start position, immediately
pull mixture off and turn battery switch
off. Have starter motor serviced.
GOV-OFF Indicates engine RPM throttle governor is
off.
CARBON Indicates elevated levels of carbon
MONOXIDE monoxide (CO) in cabin. Shut off heater
(if installed) and open nose and door vents. If hovering,
land or transition to forward flight. If
symptoms of CO poisoning (headache,
drowsiness, dizziness) accompany light,
land immediately.
FULL Indicates engine near full throttle. The
THROTTLE governor will be ineffective because it
(if installed) cannot increase throttle to maintain RPM.
Lower collective as required to extinguish
light.