Th57 Caution Lights

Front 1

ENG OUT

Back 1

Engine power failure Ng at 55 ± 3%

Hint 1

Engine power failure accompanied by an aural signal.
Monitor Nr and engine instruments and enter
autorotation if power failure is confirmed. If actuation of
the warning system is the result of Ng tachometer
generator or speed sensor switch failure, land as soon
as practical

Front 2

ENG FIRE

Back 2

Excessive heat in engine compartment

Hint 2

Refer to Engine Fire procedures.

Front 3

BATTERY HOT

Back 3

Battery case temperature is 60° ±3 °C or higher.

Hint 3

Bat Switch - OFF. Land as soon as possible
Note
Switching the main battery OFF opens the main battery relay, which causes the "STBY BATT ON" light to illuminate. As long as the ESS No. 1 bus is being powered normally, the standby battery will not be depleted.

Front 4

BATTERY TEMP

Back 4

Battery case temperature is 54° ±3 °C or higher.

Hint 4

BAT — OFF. Flight may be continued.
Note
Switching the main battery OFF opens the main battery relay, which causes the "STBY BATT ON" light to illuminate. As long as the ESS No. 1 bus is being powered normally, the standby battery will not be depleted.

Front 5

ROTOR LOW RPM

Back 5

Nr less than 90 ±3 percent.

Hint 5

Collective — Lower to preserve Nr. Check twist grip full
open. If power is not regained, follow Engine Failure
procedures. If activation of the warning system is the
result of an Nr tachometer generator failure, monitor
engine instruments and land as soon as practical.

Front 6

ENG CHIP/
CLEAR CHIP

Back 6

Metal particles on engine chip
detector.

Hint 6

Engine instruments — Check engine instruments for
secondary indications of impending failure. If these
indications exist, land as soon as possible. If no
secondary indications exist, proceed as follows:
First chip light — Press CLEAR CHIP; if ENG CHIP
light goes out, note the time and continue flight. If ENG
chip remains illuminated, land as soon as possible.
Second chip light — If within 30 minutes of the first, land
as soon as possible. If more than 30 minutes have
elapsed since the first light, press CLEAR CHIP and
proceed as with the first light.
Any subsequent chip light — If within 50 flight hours of
the first, land as soon as possible and make no attempt
to clear chip.
All chip lights shall be documented on a VIDS/MAF.

Front 7

TRANS
CHIP/CLEAR
CHIP Condition

Back 7

Metal particles on transmission chip detector or free wheeling unit

Hint 7

Instruments — Check transmission instruments for
secondary indications of impending failure. If these
indications exist, execute Imminent Transmission
Failure procedures. If no secondary indications exist,
proceed as follows:
First chip light — Press CLEAR CHIP; If TRANS CHIP
light goes out, note the time and continue flight. If
TRANS CHIP remains illuminated, land as soon as
possible.
Second chip light — If within 30 minutes of the first, land
as soon as possible. If more than 30 minutes have
elapsed since the first light, press CLEAR CHIP and
proceed as with the first light.
Any subsequent chip light — If within 50 flight hours of
the first, land as soon as possible and make no attempt
to clear chip.
All chip lights shall be documented on a VIDS/MAF.

Front 8

TRANS OIL PRESS

Back 8

Transmission oil pressure at
or below 30±2 psi.

Hint 8

Land as soon as possible.
Note
Check the transmission oil pressure with the twist
grip full open. Illumination of the TRANS OIL
PRESS caution light is common, while the twist grip
is at flight idle, after power off maneuvers; However,
the gauge should indicate positive transmission oil
pressure.

Front 9

TRANS OIL TEMP

Back 9

Transmission oil temperature
above 110 °C.

Hint 9

Land as soon as possible

Front 10

T/R CHIP

Back 10

Metal particles on tail rotor gearbox chip detector.

Hint 10

Land as soon as possible

Front 11

TRQ

Back 11

TRQ light flashes once per
second within transient range.

TRQ light flashes twice per
second when limit is
exceeded.

Hint 11

Adjust collective as required to remain within limits.
Warning
Lowering the collective to avoid an overtorque may create or exacerbate an unsafe flight profile. An overtorque is preferable to further damage or
destruction of the aircraft.

If 110 percent has been exceeded, land as soon as
possible. If the five second transient has been
exceeded, land as soon as practical.

Note
TRQ light will extinguish once out of transient and exceedence ranges. Digital readout will continue to flash twice per second if limit is exceeded.

Front 12

TOT

Back 12

TOT light flashes once per
second within transient range.

TOT light flashes twice per
second when limit is
exceeded.

Hint 12

Adjust collective as required to remain within limits.

Land as soon as Possible

Note
TOT light will extinguish once out of transient and exceedence ranges. Digital readout will continue to flash twice per second if limit is exceeded.