58 CH 9

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 the survival of the 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."

NOTE: under any partial power condition, the throttle should be checked to ensure it is fully open and, time and altitude permitting, the GOV RPM switch may be increased to ensure maximum RPM is applied

a. the indications of an engine malfunction, either partial or a complete power loss are: left yaw, drop in engine RPM, drop in rotor RPM, low RPM audio alarm, illumination of ROTOR RPM warning light, ENGINE OUT warning light, and change in engine noise.

the term EMER SHUTDOWN is defined as "engine shudown without delay."

• 1. Throttle - Close
• 2. Fuel Shutoff Valve Handle - OFF
• 3. BAT switch - OFF. Before turning the battery switch off during in-flight emergencies requiring EMER SHUTDOWN, the pilot shold consider a "MAYDAY" call, setting the transponder to EMER, and the possible adverse effects of total electrical failure.

NOTE: total electrical failure in the OH-58C will result in loss of rotor RPM indications.

The Power-off minimum rate of decent is attained at an indicated airspeed of 43 knots and 100% Rotor RPM. Refer to figure 9-2 autorotational glide characteristics chart

The maximum glide distance is attained at an indicated airspeed of 71 knots to 74 knots and 100% rotor RPM. Refer to figure 9-2 for maximum glide distance.

AUTOROTATE

• 1. AUTOROTATE
• 2. EMER SHUTDOWN. Accomplish during descent if time permits

After an engine failure in flight, an engine start may be attempted. Because the exact cause of engine failure cannot be determined in flight, the decision to attempt the start will depend on the altitude and time available, rate of descent, potential landing areas and crew assistance available. Under ideal conditions, approximately one minute is required to regain powered flight from the time the attempted start is begun. If the decision is made to attempt an in-flight start:

• 1. Throttle - Close
• 2. Attempt Start
• 3. LAND AS SOON AS POSSIBLE

Engine compressor stall may be characterized by a sharp rumble or a series of loud sharp reports, severe engine vibration and a rapid rise in TOT depending on the severity of the surge. After engine compressor stall, maneuvers requiring rapid or maximum power applications should be avoided. Should engine compressor stall occur:

• 1. Collective - Reduce
• 2. ENG DEICE and HTR switches - OFF
• 3. LAND AS SOON AS POSSIBLE

Engine overspped will be indicated by a RIGHT YAW, RAPID INCREASE in both ROTOR and ENGINE RPM, and an increase in ROTOR and ENGINE Noise. If an engine overspeed is experienced:

• 1. Collective - Increase to load the rotor and sustain engine/rotor RPM below the maximum operating limit
• 2. Throttle - Adjust until normal N2 operating RPM is attained
• 3. LAND AS SOON AS POSSIBLE Perform a power-on approach and landing by controlling the RPM manually with throttle

• a. If RPM cannot be controlled manually:
• 1. AUTOROTATE when over a safe landing area while simultaneously closing the throttle
• 2. EMER SHUTDOWN Accomplish during descent if time permits

a. If an engine underspeed occurs, the collective must be adjusted downward to maintain rotor RPM within limits. If powered flight with rotor in the green can be accomplished, LAND AS SOON AS POSSIBLE in an area that will permit a run-on landing

• b. If Engine underspeed below 94% N2 results in rotor RPM decay below minimum safe limits, should this occur:
• 1. AUTOROTATE
• 2. EMER SHUTDOWN Accomplish during descent, if time permits

• If surges in engine RPM are experienced:
• 1. GOV RPM switch - INCR for maximum RPM
• 2. Throttle - Adjust to 98% N2
• 3. LAND AS SOON AS POSSIBLE

• If engine surges are not controlled in steps 1 and 2 above, proceed as follows:
• 4. AUTOROTATE - when over a safe landing area
• 5. EMER SHUTDOWN Accomplish during decent if time permits

If the engine oil pressure is decreasing or indicates zero with accompanying loss of torque a complete loss of engine power is possible.

1. LAND AS SOON AS POSSIBLE

Should engine oil pressure drop to zero psi the oil temperature indications might not be valid.

This is a situation involving a loss of effective tail rotor thrust without a break in the drive system which cannot be stopped with full left pedal application. If LTE is experienced, simultaneously:

• 1. Pedal - Full Left
• 2. Cyclic - Forward
• 3. As recovery is effect, adjust controls for normal flight

WARNING: collective reduction will aid in arresting the yaw rate; however, if a rate of descent has been established, collective reduction may increase the rate of descent to an excessive value. The resultant large and rapid increase in collective to prevent ground or obstacle cantact may further increase the yaw rate, decrease the rotor RPM and cause an overtorque and/or over-temperature condition. Therfore, the decision to reduce collective must be based on the pilot's assessment of the altitude available for recovery. If spin cannot be stopped and crash is imminent, an autorotation may be the best course of action. Maintain full left pedal until the spin stops, then adjust to maintain heading.

A failure of the main driveshaft will be indicated by a sudden increase in engine RPM, decrease in rotor RPM, left yaw and activation of the low RPM audio, and illumination of the ROTOR RPM warning light. A transitient overspeed of N1 and N2 may occur but will stabilize. In the event of main driveshaft failure:

• 1. AUTOROTATE - Establish a power on autorotational glide. The engine must continue to operate at normal operating RPM in order to porvide tail rotor control.
• 2. EMER SHUTDOWN after landing

A clutch failing to disengage in flight will be indicated by the rotor RPM decaying with engine RPM as the throttle is reduced to the engine idle position when entering autorotational descent. This condition results in total loss of autorotational capability. If a failure occurs:

• 1. Throttle - Open
• 2. LAND AS SOON AS POSSIBLE

LAND AS SOON AS POSSIBLE

CAUTION: during engine starts using a GPU failure of the GPU could possibly result in an engine hot start. After GPU failure during start, the pilot must turn the battery switch on before accomplishing the porcedure described below.

During engine starting or shutdown, if TOT limits are exceeded, or it becomes apparent that TOT limits may be exceeded.

• 1. STARTER switch - Continue to press and hold until TOT is less than 200 C
• 2. Throttle - Close

EMER SHUTDOWN

If a fire is observed during flight, prevailing circumstances such as VMC, IMC, night, altitude, and landing areas available must be considered in order to dertermine whether to execute a power-on, or power-off landing.

• If Power-On landing:
• 1. LAND AS SOON AS POSSIBLE
• 2. EMER SHUTDOWN after landing

• If Power-Off landing:
• 1. AUTOROTATE
• 2. EMER SHUTDOWN Accomplish during descent if time permits

Prior to shutting off all electrical power, the pilot must consider the equipment that is essential to a particular flight environment that will be encountered. In the event of electrical fire, or suspected electrical fire in flight:

• 1. BAT and GEN switches - OFF
• 2. LAND AS SOON AS POSSIBLE
• 3. EMER SHUTDOWN after landing

Smoke and/or toxic fumes entering the cockpit and cabin can be exhausted as follows:

CAUTION: Do not jettison doors in flight above effective translational lift.

• 1. Vents - Open
• 2. DEFOG & VENT Switch - ON

A no-output malfunction of the generator will be indicated by a zero indication on the DC AMMETER and a DC GENERATOR caution light illumination. An attmpt may be made to put the generator back on line by accomplishing the following:

• 1. GEN FIELD, GEN and BUS RESET circuit breakers - Check in
• 2. GEN switch - RESET then GEN - Do not hold the switch in the RESET position

• If the generator is not restored, or if it goes off line again:
• 3. GEN switch - OFF
• 4. Turn OFF all unnecessary electrical equipment
• 5. LAND AS SOON AS PRACTICABLE

An abnormally high DC AMMETER indication is evidence of a high battery charging rate or a battery thermal runaway. High battery charging amperage is normal immediately after engine start and should dissipate within minutes. DC AMMETER indications of 30 AMPS or below is normal after 15 minutes of aircraft operation with all systems operating.

WARNING: Do not open battery compartment or attempt to disconnect or remove overheated battery. Battery fluid will cause burns and overheated battery will cause thermal burns and may explode.

• If high DC Amperage does not dissipate:
• 1. BAT switch - OFF
• If high DC amperage indication disappears with BAT switch off, a high battery charging rate and possible battery thermal runaway is confirmed, in this event:
• 2. LAND AS SOON AS POSSIBLE
• 3. EMER SHUTDOWN after landing

If high DC amperage indication does not dissipate, pilot should anticipate electrical fire in flight.

Hydraulic power failure will be evident when the force required for control movement increases; a moderate feedback in the cyclic and collective controls is felt and the HYD PRESS caution light illuminates. Control movements will result in normal aircraft response in every respect. In the event of hydraulic power failure:

• 1. Airspeed - Adjust as necessary to attain the most comfortable level of control movements
• 2. HYD BOOST SOL circuit breaker - Out; check for restoration of hydraulic power.

• If hydraulic power is not restored:
• 3. HYD BOOST SOL circuit breaker - In
• 4. HYD BOOST switch - OFF

WARNING: Do not return the HYD BOOSST swtitch to the ON position for the remainder of the flight. This prevents any possibility of a surge in teh hydraulic pressure adn the resulting loss of control.

5. LAND AS SOON AS PRACTICABLE at an area that will permit a run-on landing.

A landing in trees should be made when no other landing area is available. In addition to accomplishing engine malfunction emergency procedures, select a landing area containing the least number of trees of minimum height. Decelerate to minimum forward speed at treetop level and descend into the trees vertically. Appply all the remaining collective, prior to the main rotor blades entering the trees.

If ditching becomes necessary, with power available accomplish an approach to a hover above the water and:

• 1. Doors - Jettison at a hover
• 2. Crew (except pilot) and passengers - Exit
• 3. Hover a safe distance away from personnel
• 4. AUTOROTATE. Apply all remaining collective as the helicopter enters the water. Maintain a level attitude as the helicopter sinks and until it begins to roll, then apply cyclic in direction of the roll.
• 5. Pilot - Exit when the main rotor stops

If an engine failure occurs over water and ditching is imminent, accomplish engine failure emergency procedures and preoceed as follows:

• 1. AUTOROTATE Decelerate to minimum foward speed as the hilicopter nears the water. Apply all remaining collective as the helicopter enters the water. Maintain a level attitude as the helicopter sinks and until it begins to roll, then apply cyclic in direction of the roll.
• 2. Doors - Jettison
• 3. Crew and Passengers - Exit when the main rotor stops

Failure of components within the flight control system may be indicated through varying degress of feedback, binding, resistance, or sloppiness. The conditions should not be mistaken for hydraulic power failure. In the event of a flight control malfunction:

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

LAND AS SOON AS POSSIBLE

LAND AS SOON AS POSSIBLE