UH-60_EPS.txt

This section describes the helicopter systems emergencies that may reasonably be expected to occur and presents the procedures to be followed. Emergency operation of mission equipment is contained in this chapter, insofar as its use affects safety of flight. Emergency procedures are given in checklist form when applicable. A condensed version of these procedures is contained in the condensed checklist TM 1-1520-237-CL.

• The urgency of certain emergencies requires immediate and instinctive action by the
• p i l o t . The most i m p o r t a n t s i n g l e
• consideration is helicopter control. All
• procedures are subordinate to this requirement.
• The MASTER CAUTION should be
• reset after each malfunction to allow
• systems to respond to subsequent malfunctions.
• If time permits during a critical
• emergency, transmit MAYDAY call, set
• transponder to emergency, jettison external
• stores if required, turn off boost pumps, and
• lock shoulder harnesses.
• Those steps that shall be performed immediately in an
• emergency situation are underlined. These steps must be
• performed without reference to the checklist. Nonunderlined
• steps should be accomplished with use of the checklist.

• The term LAND AS SOON AS POSSIBLE is defined as landing at the nearest suitable landing area (e.g.,
• open field)without delay. (The primary consideration is to ensure the survival of occupants.)

• The term LAND AS SOON AS PRACTICABLE is defined as landing at a suitable landing area. (The primary
• consideration is the urgency of the emergency.)

The term AUTOROTATE is defined as adjusting the flight controls as necessary to establish an autorotational descent and landing.

The term EMER ENG SHUTDOWN is defined as engine shutdown without delay. Engine shutdown in flight is usually not an immediate-action item unless a fire exists. Before attempting an engine shutdown, identify the affected engine by checking ENG OUT warnings, % RPM, % TRQ, ENG OIL PRESS, TGT TEMP, and Ng SPEED.

• 1. ENG POWER CONT lever(s) - OFF.
• 2. ENG FUEL SYS selector(s) - OFF.
• 3. FUEL BOOST PUMP CONTROL
• switch(es) - OFF.

• If TGT is above 538‹C after shutdown:
• 4. AIR SOURCE HEAT/START switch(es) - As required.
• 5. ENGINE IGNITION switch - OFF.
• 6. Starter button - Press to motor engine for 30 seconds or until TGT TEMP decreases below 538‹C.

• The term LOCKOUT is defined as manual control of engine RPM while bypassing 700 ECU, or 701C
• 701D/CC DEC functions. Bypass of the engine control will be required when % RPM 1 or 2 decreases below normal demand speed.

• CAUTION
• When engine is controlled with ENG POWER CONT lever in LOCKOUT, engine response is much faster and TGT limiting system is inoperative. Care must be taken not to exceed TGT limits and keeping % RPM R and % RPM 1 and 2 in operating range.

ENG POWER CONT lever - Pull down and advance full forward while maintaining downward pressure, then adjust to set % RPM R as required. Engine control malfunctions can result in % RPM R increasing or decreasing from normal demand speed. Under certain failure conditions, % TRQ, % RPM, and Ng SPEED may not be indicating and the possibility of the ENG OUT warning and audio activating exists. The most reliable indication of engine power will be TGT TEMP.

The term EMER APU START is defined as APU start to accomplish an emergency procedure.

1. FUEL PUMP switch - APU BOOST.

• CAUTION
• Ensure that the mask blowers are
• disconnected and position the BCA MCU control knobs to OFF prior to switching from main power to APU power.

2. APU CONTR switch - ON.

• After a malfunction of equipment has occurred, appropriate emergency actions have been taken and the
• helicopter is on the ground, an entry shall be made in the Remarks Section of DA Form 2408-13-1 describing the malfunction. Ground and flight operations shall be discontinued until corrective action has been taken.

Emergency exits are shown in Figure 9-1. Emergency exit release handles are yellow and black striped.

• WARNING
• For helicopters with a non-operational roll-trim actuator, the cyclic shall be continuously held while on the ground with rotor turning. In cases where emergency exit is required prior to rotor coasting to a stop, make sure that the cyclic stick is centered until the last crewmember can depart the cockpit.
• Since the main rotor shaft has a 3° forward tilt, an exit to the right rear or left rear will provide the greatest rotor clearance safety.

Emergency equipment consists of two hand held fire extinguishers, one crash ax, and three first aid kits

• Single engine capability must be considered prior to movement of the engine power control lever. Prior to movement of either power-control lever, it is imperative that the malfunctioning engine and the corresponding powercontrol lever be identified. If the decision is made to shut down an engine, take at
• least five full seconds while retarding the ENG POWER CONT lever from FLY to IDLE, monitoring % TRQ, Ng SPEED, TGT TEMP, % RPM, and ENG OUT warning appearance. The various conditions under which engine failure may occur, prevent a standard procedure. A thorough knowledge of emergency procedures and flight characteristics will enable the pilot to respond correctly and automatically in an emergency. The engine instruments often provide ample warning of a malfunction before actual engine failure. The indications of engine malfunction, either partial or complete power loss, may be as follows: Changes in affected engine % RPM, TGT TEMP, Ng SPEED, % TRQ, ENG OIL PRESS, % RPM R, LOW ROTOR RPM and/or ENG OUT warnings and audio, and change in engine noise. The amount of change in each depends upon the type of failure, e.g., compressor stall, as opposed to complete power loss on one or both engines.

When the power available during single engine operation is marginal or less, consideration should be given to jettisoning the external stores. The engine antiice and cockpit heater switches should be turned off as necessary to ensure maximum power is available on the remaining engine.

• WARNING:
• Do not respond to ENG OUT warning
• and audio until checking TGT TEMP, Ng
• SPEED, and % RPM 1 and 2.

• 1. Collective - Adjust to maintain % RPM R.
• 2. External cargo/stores - Jettison (if required).

• If continued flight is not possible:
• 3. LAND AS SOON AS POSSIBLE.

• If continued flight is possible:
• 4. Establish single-engine airspeed.
• 5. LAND AS SOON AS PRACTICABLE.

After an engine failure in flight, an engine restart may be attempted. If it can be determined that it is reasonably safe to attempt a start, the APU should be used. Use of a crossbleed start could result in a power loss of up to 18% TRQ on the operational engine.

• Do not respond to ENG OUT warnings
• and audio until checking TGT TEMP
• and % RPM R.

AUTOROTATE.

If an engine control unit fails to the low side and the other engine is unable to provide sufficient torque, % RPM R will decrease.

• Caution:
• When engine is controlled with ENG
• POWER CONT lever in LOCKOUT,
• engine response is much faster and the TGT limiting system is inoperative. Care must be taken not to exceed TGT limits and keeping % RPM R and % RPM 1 and 2 in operating range.

• NOTE
• If %RPM R reduces from 100% to 95-96% during steady flight, check %TRQ 1 and 2. If %TRQ 1 and 2 are equal, attempt to increase %RPM R with ENG RPM trim switch.

• 1. Collective - Adjust to control % RPM R.
• 2. ENG POWER CONT lever (low % TRQ/ TGT TEMP engine) - LOCKOUT. Maintain %TRQ approximately 10% below other engine.
• 3. LAND AS SOON AS PRACTICABLE.

• control system failing to the high side. % RPM 1 and 2
• (Np) will increase with the rotor % RPM R. Increasing
• the collective will probably increase the malfunctioning
• engine’s TGT TEMP above 900‹C. If an engine control
• unit fails to the high side:
• 1. ENG POWER CONT lever (high % TRQ/ TGT TEMP engine) - Retard. Maintain % TRQ approximately 10% below other engine.
• 2. LAND AS SOON AS PRACTICABLE.

• If the affected engine does not respond to ENG POWER CONT lever movement in the range between
• FLY and IDLE, the HMU may be malfunctioning internally.

• If this occurs:
• 3. Establish single engine airspeed.
• 4. Perform EMER ENG SHUTDOWN (affected engine).
• 5. Refer to single-engine failure emergency procedure.

• It is possible for a malfunction to occur that can cause the affected engine to oscillate. The other engine will respond to the change in power by also oscillating, usually with smaller amplitudes. The engine oscillations will cause torque oscillations. The suggested pilot corrective action is
• to pull back the ENG POWER CONT lever of the suspected engine until oscillation stops. If the oscillation continues, the ENG POWER CONT lever should be returned to FLY position and the other ENG POWER CONT lever pulled back until the oscillation ceases. Once the malfunctioning engine has been identified, it should be placed in LOCKOUT and controlled manually.

• 1. Slowly retard the ENG POWER CONT lever
• on the suspected engine.
• If the oscillation stops:
• 2. Place that engine in LOCKOUT and manually
• control the power.
• 3. LAND AS SOON AS PRACTICABLE.
• If the oscillation continues:
• 4. Place the ENG POWER CONT lever back to
• FLY and retard the ENG POWER CONT
• lever of the other engine.
• When the oscillation stops:
• 5. Place the engine in LOCKOUT, manually
• control the power.
• 6. LAND AS SOON AS PRACTICABLE.

It is possible for a malfunction to occur that can cause a % TRQ split between engines without a significant change in % RPM R. The % TRQ split can be corrected by manual control of the ENG POWER CONT lever on the affected engine.

• 1. If TGT TEMP of one engine exceeds the limiter ( 700 852‹C, 701C 701D/CC 875‹C with low power engine above 50% TRQ or 901‹C with low power engine below 50%TRQ), retard ENG POWER CONT
• lever on that engine to reduce TGT TEMP. Retard the ENG POWER CONT lever to maintain torque of the manually controlled engine at approximately 10% below the other engine.
• 2. If TGT TEMP limit on either engine is not exceeded, slowly retard ENG POWER CONT lever on high % TRQ engine and observe % TRQ of low power engine.
• 3. If % TRQ of low power engine increases, ENG POWER CONT lever on high power engine - Retard to maintain % TRQ approximately 10% below other engine (the high power engine has been identified as a high side failure).
• 4. If % TRQ of low power engine does not increase, or % RPM R decreases, ENG POWER CONT lever - Return high power engine to FLY (the low power engine has been identified as a low side failure).
• 5. If additional power is required, low power ENG POWER CONT lever, momentarily move to LOCKOUT and adjust to set % TRQ approximately 10% below the other engine.
• 6. LAND AS SOON AS PRACTICABLE.

An engine compressor stall is normally recognized by anoticeable bang or popping noise and possible aircraft yaw. These responses are normally accompanied by the rapid increase in TGT TEMP and fluctuations in Ng SPEED, % TRQ, and % RPM reading for the affected engine. In the event of a compressor stall:

• 1. Collective - Reduce.
• If condition persists:
• 2. ENG POWER CONT lever (affected engine) - Retard (TGT TEMP should decrease).
• 3. ENG POWER CONT lever (affected engine) - FLY.
• If stall condition recurs:
• 4. Establish single engine airspeed.
• 5. EMER ENG SHUTDOWN (affected engine).
• 6. Refer to single-engine failure emergency
• procedure.

• 1. ENG POWER CONT lever (affected engine)- Retard (to reduce torque).
• If oil pressure is below minimum limits or if oil temperature remains above maximum limits:
• 2. Establish single engine airspeed.
• 3. EMER ENG SHUTDOWN (affected engine).
• 4. Refer to single-engine failure emergency procedure.

• Failure of the shaft may be complete or partial. Apartial failure may be characterized at first by nothing
• more than a loud high-speed rattle and vibration coming from the engine area. A complete failure will be accompanied by a loud bang that will result in a sudden % TRQ decrease to zero on the affected engine. % RPM of affected engine will increase until overspeed system is activated.

• 1. Collective - Adjust.
• 2. Establish single engine airspeed.
• 3. EMER ENG SHUTDOWN (affected engine).
• Do not attempt to restart.
• 4. Refer to single-engine failure emergency procedure.

• WARNING:
• Lightning strikes may result in loss of automatic flight control functions, engine controls, and/or electric power. Lightning strike may cause one or both engines to immediately produce maximum power with no TGT limiting or overspeed protection. Systems instruments may also be inoperative. If this occurs, the flight crew would have to adjust to the malfunctioning engine(s) ENG POWER CONT lever(s) as required to control % RPM by sound and feel. If practical, the pilot should reduce speed to 80 KIAS. This will reduce the criticality of having exactly correct rotor speed 100%.

• 1. ENG POWER CONT levers - Adjust as required to control % RPM.
• 2. LAND AS SOON AS POSSIBLE.

If autorotation entry is delayed, large sideslip angles can develop causing low indicated airspeed with the stabilator programming down. This will make it more difficult to establish or maintain adequate autorotative airspeed.

• 1. Airspeed - Adjust to 80 KIAS or above.
• 2. AUTOROTATE - Maintain airspeed at or above 80 KIAS.
• 3. ENG POWER CONT levers - OFF (during deceleration when intended point of landing is assured).

Loss of tail rotor thrust at low airspeed may result in extreme yaw angles and uncontrolled rotation to the right. Immediate collective pitch reduction must be initiated to reduce the yaw and begin a controlled rate of descent. If the helicopter is high enough above the ground, initiate a power-on descent. Collective should be adjusted so that an acceptable compromise between rate of turn and rate of descent is maintained. At approximately 5 to 10 feet above touchdown, initiate a hovering autorotation by moving the ENG POWER CONT levers - OFF.

• 1. Collective - Reduce.
• 2. ENG POWER CONT levers - OFF (5 to 10 feet above touchdown).

• WARNING:
• If the helicopter is shut down and/or hydraulic power is removed with one tail rotor cable failure, disconnection of the other tail rotor cable will occur when force from the boost servo cannot react
• against control cable quadrant spring tension. The quadrant spring will displace the cable and boost servo piston enough to unlatch the quadrant cable. a. Loss of one tail rotor cable will be indicated by appearance of the TAIL ROTOR QUADRANT caution. No change in handling characteristics should occur if only one cable fails.

• b. If both tail rotor control cables fail, a centering spring will position the tail rotor servo linkage to provide 101⁄2 degrees of pitch. This will allow trimmed flight at about 25 KIAS up to 145 KIAS (these speeds will vary with gross weight). At airspeed below 25 and above 145 KIAS, right yaw can be controlled by reducing collective. Between 25 and 145 KIAS, left yaw can be controlled by
• increasing collective.

• 1. Collective - Adjust to determine controllability (Fixed Right or Left).
• 2. LAND AS SOON AS PRACTICABLE.

• WARNING:
• Reducing collective in a left rotation will increase rate of turn with the ENG POWER CONT lever(s) at fly depending on the rate at which the ENG POWER CONT lever(s) are retarded. It is critical that the pilot on the controls maintain a level attitude, preserve RPM R, and apply cushion for the landing.

• 1. ENG POWER CONT lever(s) - Retard to begin a partial power descent.
• 2. Collective - Adjust to preserve RPM R.
• 3. ENG POWER CONT levers - OFF (5 to 10 feet above touchdown).
• 4. Collective - Adjust for landing.

• A malfunction within the yaw boost servo or tail rotor servo can produce much higher force at the pedals and the affected servo must be turned off. A hardover failure of the yaw boost servo will
• increase control forces as much as 250 pounds on the pedals.

• 1. Apply pedal force to oppose the drive.
• 2. Check other pedals for proper operation.
• 3. TAIL SERVO switch - BACKUP.

• If normal control authority is not restored:
• 4. TAIL SERVO switch - NORMAL.
• 5. BOOST switch - OFF.

• If normal control forces are not restored:
• 6. BOOST switch - ON.
• 7. Collective - Adjust to determine controllability
• for landing.
• 8. LAND AS SOON AS PRACTICABLE.

• 1. TAIL SERVO switch - BACKUP.
• 2. BACKUP HYD PUMP switch - ON.
• 3. LAND AS SOON AS PRACTICABLE.

Loss of cooling oil supply will lead to electrical and/or mechanical failure of main generators. If the malfunction is such that oil pressure decays slowly, the generators may fail before MAIN XMSN OIL PRESS caution appears.

1. LAND AS SOON AS POSSIBLE.

• If time permits:
• 2. Slow to 80 KIAS.
• 3. EMER APU START.
• 4. GENERATORS NO. 1 and NO. 2 switches -
• OFF.

• 1. ENG POWER CONT lever (affected engine) - IDLE.
• 2. LAND AS SOON AS POSSIBLE.

LAND AS SOON AS POSSIBLE.

• WARNING:
• If %RPM R decreases from 100% to below 96% with an increase in torque during steady flight with no engine malfunction, the main transmission planetary carrier may have failed. During a main transmission planetary carrier failure, it may be impossible to maintain % RPM R at 100%

• NOTE
• Decreasing % RPM R may be accompanied by a drop in transmission oil pressure of 10 psi or more, and possible unusual helicopter vibrations.

• 1. Collective - Adjust only enough to begin a descent with power remaining applied to the main transmission throughout the descent and
• landing.
• 2. LAND AS SOON AS POSSIBLE.

• WARNING
• If AC electrical power is not available, only the reserve fire bottle can be discharged and fire extinguishing capability for the #2 engine will be lost. The safety of helicopter occupants is the primary
• consideration when a fire occurs; therefore, it is imperative that every effort be made to extinguish the fire. On the ground, it is essential that the engine be shut down, crew and passengers evacuated, and fire fighting begun immediately. If time permits, a 9Mayday9 radio call should be made before the electrical power is OFF to expedite assistance from firefighting equipment and personnel. If the
• helicopter is airborne when a fire occurs, the most important single action that can be taken by the pilot is to land. Consideration must be given to jettisoning external stores and turning FUEL BOOST PUMPS and XFER PUMPS off prior to landing.

• 1. ENG POWER CONT levers - OFF.
• 2. ENG EMER OFF handle - Pull if applicable.
• 3. FIRE EXTGH switch - MAIN/RESERVE as required.

• 1. APU fire T-handle - Pull.
• 2. FIRE EXTGH switch - MAIN/RESERVE as required.

APU CONTR switch - OFF. Do not attempt restart until oil level has been checked.

• Attempt to visually confirm fire before engine shutdown or discharging extinguishing agent.
• 1. Establish single engine airspeed.
• 2. ENG POWER CONT lever (affected engine) - OFF.
• 3. ENG EMER OFF handle - Pull.
• 4. FIRE EXTGH switch - MAIN/RESERVE as required.
• 5. LAND AS SOON AS POSSIBLE.

• Prior to shutting off all electrical power, the pilot must consider the equipment that is essential to a particular flight environment which will be affected, e.g., flight instruments, flight controls, etc. If a landing cannot be made as soon as possible, the affected circuit may be isolated by selectively turning off electrical equipment and/or pulling circuit breakers.
• 1. BATT and GENERATORS switches - OFF.
• 2. LAND AS SOON AS POSSIBLE.

• WARNING
• If battery overheats, do not remove battery cover or attempt to disconnect or remove battery. Battery fluid will cause burns, and an overheated battery could cause thermal burns and may explode. Smoke or fumes in the cockpit/cabin can be eliminated as follows:

• 1. Airspeed - 80 KIAS or less.
• 2. Cabin doors and gunner’s windows - Open.
• 3. Place helicopter out of trim.
• 4. LAND AS SOON AS PRACTICABLE.

1. ENG FUEL SYS selector on affected engine - XFD.

2. LAND AS SOON AS PRACTICABLE.

LAND AS SOON AS POSSIBLE.

LAND AS SOON AS PRACTICABLE

FUEL PRESS Caution Appears.

• WARNING
• Consideration must be given to any suspected fuel system compromise. If a compromise is suspected, the pilot must make every attempt to avoid or reduce the possibility of an ignition source. A fuel leak occurring in the oil cooler access area may result in fuel and/or fumes accumulating in or around the APU/engine compartments. In such cases, APU/engine operation may result in fire. a. If the caution appears, flameout is possible. Do not make rapid collective movements. Critical situations are those where single engine flight is not possible, and the potential for fire resulting from a fuel leak is secondary to engine flameout.

If the caution appears and the situation is critical:

• 1. ENG FUEL SYS selector on affected engine -XFD.
• 2. FUEL BOOST PUMP CONTROL switches - NO. 1 PUMP or NO. 2 PUMP - ON (As applicable).
• 3. LAND AS SOON AS POSSIBLE.
• 4. EMER ENG SHUTDOWN after landing.

b. Non-critical situations are those where single engine flight is possible.

• If the caution appears, and the situation is not critical:
• 1. ENG FUEL SYS selector on affected engine - XFD.
• 2. FUEL BOOST PUMP CONTROL switches - NO. 1 PUMP or NO. 2 PUMP - OFF (As applicable).
• 3. LAND AS SOON AS PRACTICABLE.

• 1. LAND AS SOON AS POSSIBLE.
• 2. EMER ENG SHUTDOWN after landing.

• 1. SAS 1 switch - Press off.
• 2. Airspeed - Adjust (80 KIAS or less).
• 3. GENERATORS NO. 1 and NO. 2 switches -
• RESET; then ON.
• If cautions still appear:
• 4. GENERATORS NO. 1 and NO. 2 switches -
• OFF.
• 5. EMER APU START.
• 6. SAS 1 switch - ON.
• 7. If MCUs are in use: BCA MCU control knobs
• (pilot, copilot, and crewmembers) - OFF.
• 8. LAND AS SOON AS PRACTICABLE.

• CAUTION
• When the #1 ac generator is failed, and the backup pump circuit breaker is out, turn off ac electrical power before resetting the backup pump power circuit breaker, to avoid damaging the current limiters.

• 1. Affected GENERATORS switch - RESET;
• then ON.
• If caution still appears:

2. Affected GENERATORS switch - OFF.

1. Unnecessary dc electrical equipment - OFF.

• NOTE
• When only battery power is available,
• NICAD battery life is about 22 minutes day
• and 14 minutes night for a battery 80%
• charged.SLAB battery life is about 38
• minutes day and 24 minutes night for a battery
• 80% charged.

2. LAND AS SOON AS PRACTICABLE.

• 1. BATT switch - OFF; then ON. If BATTERY FAULT caution appears, cycle BATT switch
• no more than two times.
• If caution still appears:
• 2. BATT switch - OFF.

• If caution appears after ac power is applied:
• 1. BATT switch - OFF; then ON. About 30
• minutes may be required to recharge battery.
• If caution appears in flight:
• 2. BATT switch - OFF, to conserve remaining
• battery charge.

• 1. TAIL SERVO switch - BACKUP; then NORMAL.
• 2. LAND AS SOON AS PRACTICABLE.

• 1. POWER ON RESET s w i t c h e s -Simultaneously press, then release.
• 2. LAND AS SOON AS PRACTICABLE.

• LAND AS SOON AS POSSIBLE. Restrict
• control movement to moderate rates.

• Loss of both the No. 1 hydraulic pump and backup pump results in both stages of the tail-rotor servo being unpressurized.The yaw boost servo is still pressurized and the mechanical control system is still intact allowing limited tail-rotor control. Because of the limited yaw control range available, a roll-on landing 40 KIAS or above is required. Loss of both the No. 2 hydraulic pump and the backup
• pump results in the loss of pilot-assist servos.

• 1. Airspeed - Adjust to a comfortable airspeed.
• 2. BACKUP HYD PUMP switch - ON.
• If BACK-UP PUMP ON advisory still does not
• appear:
• 3. FPS and BOOST switches - Off (for #2 HYD PUMP caution).
• 4. LAND AS SOON AS POSSIBLE.

• Appearance of #1 or #2 PRI SERVO PRESS
• caution can be caused by inadvertently placing the SVO
• OFF switch on either collective control head in 1ST STG
• or 2ND STG position. Before initiating emergency
• procedure action, the pilots should check that both SVO
• OFF switches are centered.

• 1. SVO OFF switches - Check both are centered.
• 2. If the caution appears with the SVO OFF switch centered, move the SVO OFF switch to turn off the malfunctioning servo.
• 3. LAND AS SOON AS POSSIBLE.

1. LAND AS SOON AS PRACTICABLE

• If the BACK-UP RSVR LOW caution also appears:
• 2. SVO OFF switch - 1ST STG.

• WARNING
• If #2 PRI SERVO PRESS caution appears,
• establish landing attitude,
• minimize control inputs, and begin a
• descent.

3. LAND AS SOON AS POSSIBLE

• 1. POWER ON RESET s w i t c h e s - Simultaneously press then release.
• 2. LAND AS SOON AS PRACTICABLE.

• If BACK-UP RSVR LOW caution also appears:
• 3. SVO OFF switch - 2ND STG.

• WARNING
• If #1 PRI SERVO PRESS caution appears,
• establish landing attitude,
• minimize control inputs, and begin a
• descent.
• 4. LAND AS SOON AS POSSIBLE.

Pilot assist servos will be isolated; if they remain isolated, proceed as follows:

• 1. BOOST and FPS switches - Off.
• 2. LAND AS SOON AS PRACTICABLE.

• NOTE
• Because the logic module will close the
• valve supplying pressure to the pilot-assist
• servos, BOOST SERVO OFF, SAS OFF,
• and TRIM FAIL cautions will appear.

• Hardover failure of the collective boost servo will increase control forces (as much as 150 pounds)
• in the collective. The increased control forces can be immediately
• eliminated by shutting off the boost servo.
• Resulting control loads will be the same as for in-flight
• boost servo off.
• 1. BOOST switch - Off.
• 2. LAND AS SOON AS PRACTICABLE

Hardover failure of the pitch boost servo will increase the longitudinal cyclic control forces (approximately 20 pounds). The increased control forces can be immediately eliminated by shutting off SAS.

• 1. SAS (1 and 2) and FPS switches - Off.
• 2. LAND AS SOON AS PRACTICABLE.

Appearance of the BOOST SERVO OFF caution with no other cautions appearing indicates a pilot valve jam in either the collective or yaw boost servo. Control forces in the affected axis will be similar to flight with boost off.

• 1. BOOST switch - Off.
• 2. LAND AS SOON AS PRACTICABLE

• 1. AUTOROTATE. Decelerate helicopter to stop all forward speed at treetop level.
• 2. Collective adjust to maximum before main rotor
• contacts tree branches.

• The decision to ditch the helicopter shall be made by the pilot when an emergency
• makes further flight unsafe.

• 1. Approach to a hover.
• 2. Cockpit doors jettison and cabin doors open
• prior to entering water.
• 3. Pilot shoulder harness - Lock.
• 4. Survival gear - Deploy.
• 5. Personnel, except pilot, exit helicopter
• 6. Fly helicopter downwind a safe distance and
• hover.
• 7. ENG POWER CONT levers - OFF.
• 8. Perform hovering autorotation, apply full collective to decay rotor RPM as helicopter settles.
• 9. Position cyclic in direction of roll.
• 10. Exit when main rotor has stopped.

• If ditching is imminent, accomplish engine malfunction emergency procedures. During descent, open cockpit and cabin doors. Decelerate to zero forward speed as the helicopter nears the water. Apply full collective as the helicopter nears the water.
• Maintain a level attitude as the helicopter sinks and until it begins to roll; then apply cyclic in the direction of the roll.Exit when the main rotor is stopped.
• 1. AUTOROTATE.
• 2. Cockpit doors jettison and cabin doors open
• prior to entering water.
• 3. Cyclic - Position in direction of roll.
• 4. Exit when main rotor has stopped

Failure of components within the flight controlsystem may be indicated through varying degrees of feedback, binding, resistance, or sloppiness. These conditions should not be mistaken for malfunction of the AFCS.

• b. Failure of a main rotor component may be indicated by the sudden onset or steady increase in main rotor vibration or unusual noise. Severe changes in lift characteristics and/or balance condition can occur due to blade strikes, skin separation, shift or loss of balance weights, or other material. Malfunctions may result in severe main rotor flapping. The severity of vibrations may be minimized by reducing airspeed.
• If the main rotor system malfunctions:

• WARNING
• Danger exists that the main rotor system
• could collapse or separate from the
• aircraft after landing. Exit when main
• rotor has stopped.

• 1. LAND AS SOON AS POSSIBLE.
• 2. EMER ENG(S) SHUTDOWN after landing.

• Erratic electrical input to a SAS actuator can result in moderate rotor tip path oscillations that are often accompanied with pounding sounds or knocking which may be felt in the cyclic or pedal controls. No SAS malfunction, however, can physically drive the pilots’ flight controls. Failure of SAS 2 is usually, but not necessarily, followed by a failure/advisory indication. Failure of a SAS 1component will not be accompanied by a failure/ advisory indication as SAS 1 does not contain diagnostic apabilities.
• If the helicopter experiences erratic motion of the rotor tip path without failure/advisory indication:
• 1. SAS 1 switch - Off.
• If condition persists:
• 2. SAS 1 switch - ON.
• 3. SAS 2 switch - Off.
• If malfunction still persists:
• 4. SAS 1 and FPS switches - Off.

• POWER ON RESET s w i t c h e s -
• Simultaneously press and then release.

Simultaneously press and then release

FPS switch - Off.

• An FPS malfunction will be detected by the SAS/ FPS computer, which will disengage FPSfunction in theapplicable axis and activate the FLT PATH STAB caution and corresponding FAILURE ADVISORY light.
• POWER ON RESET s w i t c h e s -
• Simultaneously press and then release.
• If failure returns, control affected axis manually.

• WARNING
• If the airspeed fault advisory light is illuminated, continued flight above 70 KIAS with the stabilator in the AUTO
• MODE is unsafe since a loss of the airspeed signal from the remaining airspeed sensor would result in the stabilator slewing full-down. If the airspeed fault light remains illuminated on the AFCS panel:

• NOTE
• Use of the cyclic mountedstabilator slew-up switch should be announced to the crew to minimize cockpit confusion.
• 3. Manually slew stabilator - Adjust to 0° if above 40 KIAS. The preferred method of manually slewing the stabilator up is to use the cyclic mounted stabilator slew-up switch.

4. LAND AS SOON AS PRACTICABLE.

• If failure occurs:
• POWER ON RESET s w i t c h e s -
• Simultaneously press and then release.

If failure returns, control affected axis manually

Both yaw and roll trim actuators incorporate slip clutches to allow pilot and copilot inputs if either actuator should jam. The forces required to override the clutches are 80-pounds maximum in yaw and 13-pounds maximum in roll.

LAND AS SOON AS PRACTICABLE.

An Auto Mode Failure will normally result in the stabilator failing in place. The indications to the pilots of the failure are a beeping audio warning, and MASTER CAUTION and STABILATOR caution appearing when the automatic mode fails.The position of failure may vary from the ideal programmed position by 10‹ at 30 KIAS to 4‹ at 150 KIAS. If an approach is made with the stabilator fixed 0‹, the pitch attitude may be 4‹ to 5‹ higher than normal in the 20 to 40 KIAS range.

• An Auto Mode Failure will normally result in the stabilator failing in place. The indications to the pilots of the
• failure are a beeping audio warning, and MASTER CAUTION and STABILATOR caution appearing when the automatic mode fails.The position of failure may vary from the ideal programmed position by 10‹ at 30 KIAS to 4‹ at 150 KIAS. If an approach is made with the stabilator
• fixed 0‹, the pitch attitude may be 4‹ to 5‹ higher than normal in the 20 to 40 KIAS range.

• If an AUTO Mode Failure Occurs:
• NOTE
• Use of cyclic mounted stabilator slew-up
• switch should be announced to the crew to
• minimize cockpit confusion.
• 1. Cyclic mounted stabilator slew-up switch - Adjust if necessary to arrest or prevent nose down pitch rate.
• 2. AUTO CONTROL switch - Press ON once after establishing a comfortable airspeed.
• If automatic control is not regained:
• 3. Manually slew stabilator - Adjust to 0‹ for flight above 40 KIAS or full down when airspeed is below 40 KIAS. The preferred method of manually slewing the stabilator up is to use the cyclic mounted stabilator slew-up switch.
• 4. LAND AS SOON AS PRACTICABLE.
• If manual control is not possible:
• 5. STAB POS indicator - Check and fly at or below KIAS LIMITS shown on placard.
• 6. LAND AS SOON AS PRACTICABLE

• If an uncommanded nose down pitch attitude occurs:
• 1. Cyclic - Adjust as required.
• 2. Collective - Maintain or increase.
• 3. Cyclic mounted stabilator slew-up switch - Adjust as required to arrest nose down pitch rate.
• 4. MAN SLEW switch - Adjust to 0‹ at
• airspeeds above 40 KIAS and full down at airspeeds below 40 KIAS.
• 5. LAND AS SOON AS PRACTICABLE.
• If an uncommanded nose up pitch attitude occurs:
• 1. Cyclic - Adjust as required.
• 2. Collective - Reduce as required.
• 3. MAN SLEW switch - Adjust to 0‹ at airspeeds above 40 KIAS and full down at airspeeds below 40 KIAS.
• 4. LAND AS SOON AS PRACTICABLE.