Note

An excessive rise in TOT, TOT rapidly accelerating through 840 °C, and/or

the battery voltage stabilized below 17 volts on starter engagement

particularly when combined, indicates an increased potential for a hot start

and may necessitate aborting the start to preclude an overtemp.

In the event of a mechanical failure in the engine or control linkage, the twist grip may not secure fuel flow to the

engine. Turning the fuel valve off will provide the only means of securing fuel flow if the twist grip fails to control

TOT.

Note

If a subsequent start is attempted, utilize a GPU.

Procedures:

*1. Twist grip — Close.

*2. Starter — Secure after TOT stabilizes at 400 °C or below.

Procedures:

*1. ENG ANTI−ICING — ON.

*2. PITOT HEAT switches — HEAT.

(c)*3. Alternate static source knob — As required.

*4. Descend or climb to a warmer temperature or vacate clouds/moisture.

If unable to get clear of icing conditions:

*5. Land as soon as possible.

Warning:

Monitor engine instruments and be prepared for partial or complete power loss.

A post shutdown fire is an internal engine fire that occurs in an engine that is stopped or coasting down.

Indications:

1. TOT rises above 400 °C.

2. Flames or smoke coming from engine.

Procedures:

*1. Starter — Engage.

*2. Fuel valve — OFF.

*3. Igniter circuit breaker — Pull.

*4. Starter — Secure after fire is extinguished.

Indications:

1. Fire warning light illuminated.

2. Smoke. 3. Fuel fumes. 4. Fire.

5. Indication from ground personnel.

6. Grinding noises or apparent drive train damage.

Procedures:

*1. Twist grip — Close.

*2. Fuel valve — OFF.

*3. BAT switch — OFF.

*4. STBY ATT IND switch — OFF.

*5. Rotor brake — Engage immediately.

*6. Helicopter — Egress and use the fire bottle as required to extinguish the fire or get clear of the aircraft.

WARNING:

After exiting aircraft, beware of rotor blades.

*1. Land as soon as possible.

Warning: With suspected transmission malfunctions, the pilot should make an approach with minimum power change to minimize changes to transmission torque.

Note

- Check the transmission oil pressure with the twist grip full open.

Illumination of theTRANSOILPRESS caution light is common,while the

twist grip is at flight idle; however, the gauge should indicate positive

transmission oil pressure.

- There is no detrimental effect to the transmission system with oil pressure

between 50 to 70 psi with transmission temperaturewithin limits. Pressure

indications between 50 to 70 psi shall be documented on a MAF upon

completion of flight.

If either oil temperature gauge indicator exceeds red line limitations:

*1. Land as soon as possible.

If either oil temperature gauge fluctuates or falls to zero:

*2. Land as soon as practical.

If abnormal transmission temperature or pressure indications are accompanied by the illumination of the TRANS CHIP light or abnormal sound from the transmission area:

*1. Land immediately.

Warning: Do not autorotate; minimize power changes.

*2. Lock harness.

If Ng or TOT falls to zero or fails to rise and fall with corresponding power changes:

1. Monitor other engine instruments.

2. Avoid high power settings.

3. Land as soon as practical.

Note

Failure of the Ng tachometer generator is usually accompanied by actuation of the ENG OUT warning horn and caution light.

If the torquemeter needle is unusually low or falls to zero with a corresponding digital readout, it is probable that the torque line has ruptured. A restrictor fitting in the wet line will slow the rate of engine oil loss, but will not stem the flow.

Procedures:

*1. Monitor engine instruments.

*2. Land as soon as possible.

The torquemeter incorporates a transducer between thewet line and the gauge. If the needle falls to zero and the digital readout is extinguished, the cause is a loss of electrical power to the indicator.

Procedures:

1. Monitor engine instruments.

2. Check TRQ circuit breaker — In.

If circuit breaker resets:

3. Flight may be continued.

If circuit breaker was not popped or does not reset:

4. Land as soon as practical.

Note

Some minor torque fluctuation is normal and should not be cause for

concern.

Indications:

Fumes in cockpit.

Smoke in cockpit.

Equipment failure.

Procedures:

*1. ECS and DEFOG blower — OFF.

*2. Vents/windows — Open.

*3. Slip or skid aircraft to eliminate smoke and fumes.

*4. Land as soon as possible.

Indications:

Unusual fuel usage.

Fuel fumes in cockpit.

Procedures:

*1. Land as soon as possible.

If time and altitude permit:

*2. Transmit position and intentions.

*3. Unnecessary electrical equipment — Secure.

WARNING
If an air leak exists in the fuel lines between the boost pumps and engine, turning off all electrical power could cause an engine flameout due to a total loss of boost pump pressure.

When on deck:

4. Shutdown — Completed.

5. Helicopter — Exit.

Indications:

Loadmeter to zero.

MAIN GEN or GEN FAIL caution light — On.

Dc voltmeter indicates battery voltage.

c-Voltmeter indicates 0.

Procedures:

1. MAIN GEN FIELD and MAIN GEN RESET circuit breakers — Check in.

2. MAIN GEN switch — Reset, then ON.

If generator power is not restored:

3. MAIN GEN switch — OFF.

Note

Prior to shutting off all electrical power, the pilot must determine the

equipment that is essential to the particular flight environment that will be

encountered (e.g., flight instruments and fuel boost pumps).

4. Unnecessary electrical equipment — OFF.

c-5. NORMAL/RECOVER switch — RECOVER as desired.

c-6. Voltmeter Select Switch — MAIN BAT.

7. Descend below 6,000 feet PA.

8. Land as soon as practical.

If power is restored:

9. Continue flight.

Warning

-With the battery switch OFF or battery exhaustion, both fuel boost pumps

are inoperative.

-With one or both boost pumps inoperative, minimum fuel is 20 gallons;

10 gallons is unusable.

-Be prepared for a possible electrical and/or engine compartment fire

because of excessive wiring load or generator meltdown.

Indications:

HYDRAULIC PRESSURE light.

Increased force required for control movement.

Feedback in control.

Procedures:

1. Airspeed — Adjust (to obtain most comfortable control movement level).

2. HYDRAULIC BOOST switch — Check ON.

3. HYD BOOST circuit breaker — Pull.

If system is restored:

4. Land as soon as practical.

If system is not restored:

5. HYD BOOST circuit breaker — In.

6. HYDRAULIC BOOST switch — OFF.

7. FORCE TRIM (FT) — ON.

c-8. AFCS STAB — ON.

c-9. AFCS ALT — OFF.

10. Land as soon as practical.

Indications:

Cyclic/collective control displaces to abnormal position.

Pilot control of cyclic/collective is difficult or impossible.

Procedures:

*1. HYDRAULIC BOOST switch — OFF.

WARNING:Hydraulic system will not secure if HYD BOOST circuit breaker is out.

*2. Helicopter — Regain control.

*3. Airspeed — Adjust (to obtain most comfortable control movement level).

*4. Land as soon as possible.

WARNING: In the event of a complete loss of electrical power in the TH−57B or a failure of the ESS No. 2 bus in the TH−57C, the hydraulic system will reenergize in the malfunction mode. The pilot will be unable to override the hydraulic boost solenoid.

ENG CHIP/

CLEAR CHIP

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:

1.First chip light — Press CLEAR CHIP; if ENG CHIP light goes out, note the time and continue flight.

If ENG chip remains illuminated

2.land as soon as possible.

Second chip light—If within 30minutes of the first,

3.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.

Indications:

FUEL PUMP caution light.

Indicated fuel pressure of zero (dual−pump failure).

Procedures:

*1. Descent — Initiate if above 6,000 feet PA and flight permits.

*2. Fuel pressure and quantity — Note.

Warning: With one or both boost pumps inoperative, minimum fuel is 20 gallons; 10 gallons is unusable.

Indications:

Fire light.

Smoke.

Flames.

Procedures:

Warning: Be prepared for complete power loss.

*1. Confirm existence of fire.

If fire exists:

*2. Land immediately.

*3. Emergency shutdown — Complete after landing.

If fire not confirmed:

*4. Land as soon as possible.

Battery case temperature is:  60° ±3 °C/54° ±3 °C or higher

BAT switch — OFF. Land as soon as possible./Flt may be cont

Note Switching the Main Battery Off opens the main battery relay, which causes the “STBY BATT ON” light to illuminate. As long as theESS No. 1 bus is being powered normally, the standby battery will not be depleted. 

Indications:

Nr increase. Nf increase. Ng increase. TOT increase.

Right yaw.

Engine noise increase.

Procedures:

*1. Twist grip — Reduce (to maintain Nf/Nr in operating range).

*2. Collective/twist grip — Coordinate.

Note

The Nf overspeed must be controlled by coordinating collective and twist grip.

*3. Land as soon as possible.

Note

Bleed valve flutter is a mild pop or series of pops and may occur while opening the twist grip. This bleed valve flutter is considered normal as the bleed valve is operating as designed. The bleed valve flutter may cause slight momentary TOT and torque changes. Any additional indications should be reason to classify this as a compressor stall.

Indications:

Popping, rumbling or loud banging.

Abnormal vibrations.

Rapid rise or fluctuations in TOT.

Torque fluctuations with yaw kicks.

Ng fluctuation.

Loss of power.

WARNING Be prepared for complete power loss.

Procedures:

*1. Collective — Reduce.

Note

Power (collective) reduction will often eliminate compressor stalls.

*2. ENG Anti--ice switch — ON.

*3. Cabin Heat Valve — ON.

If compressor stall persists and the aircraft is uncontrollable:

*4. Autorotate.

*5. Twist grip — Flight Idle.

Note

Depending on time, altitude, and suitability of the landing site the pilotmay

attempt to increase the twist grip after the compressor stall has cleared to affect a power on landing. Increasing the twist grip may re--aggravate the compressor stall.

If compressor stall clears or the aircraft is controllable:

*6. Land as soon as possible.

CAUTION

When accelerating the rotor system during the initial rotor engagement or after power offmaneuvers, exceeding 40 percent torquemay induce engine chugging which may induce a compressor stall.

Note

Mild compressor stalls may occur that will allow powered flight if TOT is within operating limits.

Indications:

Nr decrease.

Rapid settling.

Left yaw.

ROTOR LOW RPM caution light and audio.

ENGINE OUT caution light and audio.

Procedures:

*1. Autorotate.

*2. Shoulder harness — Lock.

If time and altitude permit:

*3. Mayday — Transmit.

*4. Transponder — Emergency.

Procedures:

*1. Autorotate.

*2. Starter — Engage.

*3. Twist grip — Check, Full open.

Note

The twist grip can be left in the full open position since fuel flow during the start will be on the normal acceleration schedule.

If light−off does not occur:

*4. Twist grip — Close.

Note

If time and altitude permit multiple attempts can be made to perform a normal start.

If light−off occurs:

*5. Twist grip — Full open.

*6. Land as soon as possible.

Note

Main generator and BUS/TIE RELAY (TH−57C) may need to be reset.

Indications:

Nr decrease.

Nf indication higher than Nr.

Left yaw.

Loud bang/sound of overspeeding engine.

Low torque.

Procedures:

*1. Autorotate.

*2. Twist grip — Adjust, if necessary, to maintain Nf in operating range.

Warning The engine must continue to operate to provide tail rotor drive. Tail rotor effectiveness may be lost if Nf is allowed to go below 80 percent.

Note The Nf governor should bring the Nf back to 100% with the twist grip full open.

When on deck:

*3. Emergency shutdown — Complete.

Indications:

Loadmeter shows excessive load.

Dc voltmeter shows excessive load.

Smoke.

Fumes.

Sparks.

Procedures:

*1. BAT switch — OFF.

c-*2. STANDBY GEN switch — OFF.

c-*3. If in VMC, STBY ATT IND switch — OFF.

*4. MAIN GEN switch — OFF.

If fire persists:

*5. Land immediately.

If fire extinguishes:

*6. Land as soon as possible.

If electrical power is required to restore minimum equipment for continued flight, proceed as follows:

7. All circuit breakers — Pull.

c-8. Check BAT RELAY circuit breaker — In.

9. BAT switch — ON.

10. MAIN GEN FIELD and MAIN GEN RESET circuit breakers — In.

11. MAIN GEN switch — Reset, then ON.

c-12. STBY GEN RELAY circuit breaker — In.

c-13. STBY GEN switch — ON.

c-14. STBY ATT IND switch — ON.

15. Circuit breakers for essential equipment — In one at a time in order of importance.

Note

 -Ensure corresponding bus supply circuit breakers are in to provide power

to desired electrical equipment.

 -Voltmeter will not indicate battery voltage until battery bus supply and

voltmeter circuit breakers are in.

 -Flight operation can be maintained without battery and generator.

Instruments powered by the 28 Vdc power, however, will be inoperable.

Procedures:

*1. Affected equipment — Secure.

*2. Affected circuit breakers — Pull.

If fire persists:

*3. Electrical Fire — Unknown Origin procedure — Execute.

If fire extinguishes:

4. Land as soon as practical.