Malfunction Analysis/EPs Flashcards
Power Loss (Partial or Complete)
Indications
Analyze/Action
Indications:
- Left Yaw
- Drop in Engine RPM (Nf)
- Drop in Rotor RPM (Nr)
- Low RPM Audio Alarm 93 ±2%
- Illumination of RPM Warning Light 93 ±2%
- Change in engine noise
Analyze/Take Action:
- Confirm engine malfunction by one or more other indications
- Is erratic engine operation or power surging controllable by reduced power
- If flight is not possible, close the throttle completely and complete autorotation
Engine Compressor Stall
Indications
Indications:
- Sharp rumble or series of loud sharp reports, severe engine vibration and rapid rise in engine gas temperature (EGT)
Inlet Guide Vane Actuator Failure
Indications
Indications:
- CLOSED position: maximum torque = 35% to 40% [power applications above 35-40% torque will result in deterioration of Nf and Nr while increasing Ng]
- OPEN position: Probability of no indications. Acceleration times from lower Ng settings may be noticeable.
Droop Compensator Failure
Indications
Analyze/Action
Indications:
- Engine RPM (Nf) fluctuates excessively during application of collective pitch.
- Tend to overspeed when collective is decreased.
- Tend to under-speed when collective is increased.
Analyze/Take Action:
- If unable to maintain operating RPM within limits – GOV SWITCH - EMER
Engine Overspeed (Nf governor or fuel control)
Indications
Analyze/Action
Indications:
- Right Yaw
- Rapid increase in both Nr and Nf
- Illumination of RPM Warning Light 103 ±1%
- Increase in engine noise
Analyze/Take Action:
- Nf governor malfunction or fuel control malfunction [same initial indications]
- Nf governor malfunction: the Nf can be controlled by throttle reduction
- Fuel control malfunction: Throttle reduction will not affect Nf RPM. Requires GOV SWITCH EMER
- Nf accessory gearbox failure: Manifest itself as Nf governor failure. Nf tachometer and torque gauges will fail
Engine Underspeed (Nf governor)
Indications
Analyze/Action
Indications:
- Left Yaw
- Drop in Engine RPM (Nf)
- Drop in Rotor RPM (Nr)
Analyze/Take Action:
- At low altitude/low airspeed the malfunction must be treated as an engine failure
- Incr/decr switch to maximum and GOV SWITCH EMER if underspeed not corrected.
Engine Chip Detector
Indications
Analyze/Action
Indications:
- ENG CHIP DET warning light illuminates
Analyze/Take Action:
- LAND AS SOON AS POSSIBLE
Complete Loss of Tail Rotor Thrust (Pilot must discern if the aircraft is in controlled or uncontrolled flight)
Indications
Analyze
Indications:
- Right Yaw
- Left Nose Tuck
- Pedal input has no effect
Analyze/Take Action:
- Controllability will depend on airspeed [above 60 knots], loss of tail rotor components, and CG shift.
- Adjusting Nr to minimum [91%] may help control right yaw
- A right turn above 60 knots my help stabilize the aircraft
- Opening left cabin door and closing the right cabin door may allow drag to counter some of the right yaw
- Landing must be planned ahead to be either autorotative or power-on shallow approach and slide landing
- Judicious use of the throttle and collective will help maintain landing area alignment during a slide landing
Fixed Pitch Failures (Tail Rotor)
Indications
Analyze/Action
Indications:
- Lack of directional response when a pedal is pushed
- Pedals are in a locked position
- Aircraft goes out of trim
Analyze/Take Action:
- Locked Pedals: Determine which pedal is forward of neutral
- Perform controllability check to determine the best airspeed, torque, and Nf and Nr for straight/level flight
- Plan a power-on shallow approach and slide landing
- Coordinate the use of cyclic, collective, and throttle to maintain landing area alignment during a slide landing
Main Driveshaft Failure
Indications
Analyze/Action
Indications:
- Left Yaw
- Increase in Engine RPM (Nf)
- Decrease in Rotor RPM (Nr)
- Low RPM Audio Alarm 93 ±2%
- Illumination of RPM Warning Light 93 ±2%
Analyze/Take Action:
- Similar to engine failure except the engine will possibly overspeed resulting in split Nf and Nr needles
- Results in complete loss of power to the rotor (Nr)
Clutch Fails To Disengage (When throttle is reduced to the engine idle position when entering autorotational descent)
Indications
Analyze/Action
Indications:
- Rotor RPM (Nr) decaying with engine RPM (Nf)
Analyze/Take Action:
- Total loss of autorotational capability.
Clutch Fails To Re-engage (During recovery from autorotational descent)
Indications
Analyze/Action
Indications:
- Reverse needle split (engine RPM higher than rotor RPM)
Analyze/Take Action:
- Do not delay shutting down the engine to prevent the possibility of the clutch re-engaging in the autorotative flare causing the aircraft to yaw excessively and roll over at touchdown.
Transmission Oil – Hot or Low Pressure
Indications
Indications:
- XMSN OIL HOT and/or XMSN OIL PRESS caution lights or limits on gauges exceeded
- Temp limit = 110 degrees C; Pressure limit = 70 psi high; 30 ± 3 psi low
Transmission and Tail Rotor Chip Detectors
Indications
Analyze/Action
Indications:
- CHIP DET warning light illuminates
Analyze/Take Action:
- CHIP DET requires the use of BOTH/TAIL/XMSN switch on center pedestal to determine location of chip
- If XMSN is determined to be location, check the XMSN CHIP IND PANEL (Upper Mast, PLNTY, or Sump/Oil)
Engine Fire – Start
Indications
Analyze/Action
Indications:
- Abnormally rising EGT and/or EGT exceeding limits
- EGT limit prior to engine stabilization (NG<68%) = 950 Degrees C (max engine start limit)
- EGT limit after engine stabilization (NG>68% for 5 seconds) = Yellow: 820-880 (30 min); Red: 880
- May be accompanied by smoke or flames
Analyze/Take Action:
- Continue starting: starter ignition trigger switch held until EGT is in the normal range
- Remove fuel from engine: close the throttle; fuel switches off (main and start fuel)
