Systems and Equipment Malfunctions

Objective

Upon completion of this lesson, the CFI candidate will demonstrate the ability to teach systems and equipment malfunctions in helicopters by explaining the causes, recognition, and appropriate responses to various emergency scenarios. The candidate will effectively instruct students on proper emergency procedures while emphasizing risk management and crew resource management principles, meeting the standards of ACS task HI.XIII.H.

Content

Introduction to Systems and Equipment Malfunctions

Systems and equipment malfunctions in helicopters require immediate recognition, proper analysis, and appropriate response. As flight instructors, we must prepare students to handle these emergencies with confidence and precision. The key to successful emergency management lies in three fundamental principles: maintain aircraft control, analyze the situation, and take appropriate action.

Powerplant Malfunctions (HI.XIII.H.K1)

Turbine Engine Failures:

• Compressor stall: Caused by disrupted airflow, contamination, or rapid throttle movements. Symptoms include loud banging, vibration, and possible flames from exhaust
• Hot start: Excessive exhaust gas temperature during start, often from too much fuel or insufficient airflow
• Turbine overspeed: Governor failure or sudden load changes can cause dangerous overspeed conditions
• Fuel control unit failure: Results in inability to control power, requiring immediate autorotation
• Oil system failure: Loss of oil pressure leads to rapid engine failure due to bearing seizure

Piston Engine Failures:

• Carburetor ice: Venturi effect and fuel vaporization create ice formation, restricting airflow
• Fuel system problems: Contaminated fuel, fuel pump failure, or blocked fuel lines
• Ignition system failure: Magneto problems, fouled spark plugs, or broken ignition wires
• Mechanical failure: Broken connecting rods, seized pistons, or valve failures

Electrical System Malfunctions (HI.XIII.H.K2a)

Electrical failures can range from minor inconveniences to major emergencies depending on aircraft systems affected. Modern helicopters rely heavily on electrical power for flight controls, navigation, and communication.

Common electrical malfunctions:

• Generator/alternator failure: Loss of charging capability, battery depletion
• Battery failure: Complete electrical system loss in single-battery aircraft
• Bus bar failures: Partial system loss affecting specific circuits
• Circuit breaker trips: Individual system protection activation

Teaching technique: Use the analogy of home electrical systems - when a circuit breaker trips at home, you don’t just reset it blindly; you investigate why it tripped.

Flight Instrument Malfunctions (HI.XIII.H.K2b)

Attitude Indicator Failure:

• Vacuum pump failure in vacuum-driven systems
• Electrical failure in electrically-driven systems
• Precession or tumbling during unusual attitudes
• Recognition: Instrument shows impossible attitudes during straight and level flight

Airspeed Indicator Problems:

• Pitot tube blockage from ice, insects, or debris
• Static port blockage affecting pressure differential
• Instrument internal mechanism failure

Heading Indicator Issues:

• Precession requiring periodic adjustment
• Vacuum system failure in vacuum-driven instruments
• Magnetic compass deviation during turns

Pitot-Static System Malfunctions (HI.XIII.H.K2c)

The pitot-static system provides critical flight data through differential and static pressure measurements.

Pitot tube blockage:

• Airspeed reads zero or shows decreasing values during climb
• Vertical speed and altitude indicators function normally
• Caused by ice, insects, or protective covers left on

Static port blockage:

• Airspeed indicator still functions but reads incorrectly
• Altimeter shows altitude at time of blockage
• Vertical speed indicator shows zero
• Emergency: Break static system instrument glass as last resort

Electronic Flight Instrument Display Malfunctions (HI.XIII.H.K2d)

Modern helicopters increasingly use glass cockpit displays that can fail completely or partially.

Complete display failure:

• Reversion to backup instruments
• Battery backup systems engagement
• Possible loss of engine parameters, navigation, and flight data

Partial display failure:

• Individual screen failures in multi-screen systems
• Specific parameter loss while maintaining other functions
• Symbology errors or frozen displays

Landing Gear Malfunctions (HI.XIII.H.K2e)

Retractable Gear Systems:

• Hydraulic pressure loss preventing normal extension/retraction
• Mechanical linkage failure
• Position indicator failures
• Emergency extension procedures using backup systems

Fixed Gear Considerations:

• Skid tube damage from hard landings
• Cross-tube structural damage
• Ground handling wheel failures

Inoperative Flight Controls (HI.XIII.H.K2f)

Flight control failures in helicopters are particularly critical due to the inherent instability of rotorcraft.

Hydraulic Power Control Failures:

• Sudden increase in control forces
• Reduced control authority
• Possible control binding or restriction
• Emergency procedures for manual reversion

Mechanical Control Failures:

• Broken control linkages
• Seized control surfaces
• Damaged swashplate mechanisms
• Tail rotor control failures

Hydraulic System Failures (HI.XIII.H.K2g)

In helicopters equipped with hydraulic systems, failure requires immediate recognition and response.

Symptoms of hydraulic failure:

• Sudden increase in cyclic and collective forces
• Control feel changes
• Reduced control response
• Possible control binding

Emergency procedures:

• Reduce airspeed to minimize control forces
• Prepare for increased physical demands
• Execute precautionary landing

Vibration Analysis (HI.XIII.H.K3)

Understanding helicopter vibrations requires knowledge of rotor system dynamics and mechanical components.

Low Frequency Vibrations (1/rev):

• Main rotor system out-of-track and balance
• Main rotor blade damage or ice accumulation
• Hub assembly problems
• Engine mount issues

Medium Frequency Vibrations (Engine RPM related):

• Engine internal problems
• Cooling fan imbalance
• Accessory drive issues
• Transmission input problems

High Frequency Vibrations (Tail rotor related):

• Tail rotor out-of-track and balance
• Tail rotor blade damage
• Tail rotor gearbox problems
• Drive shaft issues

Fire and Smoke Procedures (HI.XIII.H.K4)

Fire represents one of the most serious emergencies in aviation.

Engine Fire:

• Immediate autorotation entry
• Fuel shutoff and mixture to idle cutoff
• Electrical master switch off
• Fire extinguisher if available
• Emergency landing

Electrical Fire:

• Master switch off to isolate electrical system
• Ventilation to clear smoke
• Fire extinguisher if source identified
• Emergency landing

Cockpit/Cabin Fire:

• Land immediately
• Evacuate aircraft quickly
• Use fire extinguisher on external fires only

Aircraft-Specific Malfunctions (HI.XIII.H.K5)

Each helicopter type has unique systems and potential failure modes that instructors must understand thoroughly. Examples include:

• Robinson helicopters: Low rotor RPM warnings and recovery
• Bell helicopters: Hydraulic boost system peculiarities
• Eurocopter: FADEC system failures and reversionary modes

Risk Management Considerations

Startle Response (HI.XIII.H.R1): The initial reaction to unexpected emergencies can cause pilots to freeze or make inappropriate control inputs. Training must include startle effect recognition and mitigation through:

• Practiced emergency procedures
• Mental rehearsal techniques
• Progressive emergency training
• Stress inoculation through realistic scenarios

Checklist Usage (HI.XIII.H.R2): Emergency checklists provide structured responses but must be used appropriately:

• Immediate action items from memory first
• Checklist confirmation after aircraft control established
• Time-critical versus time-available emergencies
• Single-pilot versus crew coordination considerations

Task Prioritization and Situational Awareness (HI.XIII.H.R3): Emergency situations create high workload environments requiring priority management:

• Aviate, navigate, communicate priority structure
• Workload distribution techniques
• Maintaining awareness of aircraft energy state
• Avoiding fixation on single problems

Undesired Aircraft State (HI.XIII.H.R4): Emergency procedures must prevent creating additional hazards:

• Avoiding low rotor RPM during autorotation entry
• Maintaining positive aircraft control during system failures
• Energy management during emergency approaches
• Crew coordination to prevent conflicting control inputs

Common Errors (HI.XIII.H.K6)

Recognition Errors:

• Misidentifying emergency type leading to inappropriate response
• Delayed recognition due to subtle initial symptoms
• Fixation on single instruments rather than overall aircraft state

Procedural Errors:

• Failure to follow memory items in correct sequence
• Inappropriate use of checklists during time-critical phases
• Inadequate crew coordination and communication

Flight Management Errors:

• Excessive altitude loss during autorotation entry
• Poor energy management during emergency approaches
• Failure to maintain aircraft control while managing emergency

Schedule

Equipment

• FAA-H-8083-21A Helicopter Flying Handbook, Chapters 11-12
• Aircraft-specific Pilot’s Operating Handbook/Flight Manual
• Emergency checklist cards for aircraft type
• Cockpit poster or diagram showing instrument locations
• Vibration frequency chart for helicopter systems
• Whiteboard or flip chart for emergency flow diagrams
• Video examples of helicopter emergency procedures (if available)
• Emergency equipment demonstration items (fire extinguisher, flashlight)

Instructor Actions

The CFI candidate will demonstrate teaching proficiency by:

1. Explaining powerplant failures using clear analogies (comparing turbine compressor stall to a car engine backfire, explaining oil system importance like human circulatory system)

2. Demonstrating systematic emergency analysis using the “maintain control, analyze, act” framework while walking through at least four different emergency scenarios specified by the evaluator

3. Teaching vibration recognition by correlating frequency ranges with specific helicopter components and explaining the physical causes using rotor dynamics principles

4. Instructing fire and smoke procedures with emphasis on immediate action items and decision-making priorities

5. Facilitating risk management discussions by presenting realistic scenarios and guiding student analysis of startle response, checklist usage, and task prioritization

6. Demonstrating proper checklist usage by showing the difference between immediate action items (from memory) and follow-up checklist confirmation

7. Correcting common errors through positive reinforcement techniques, explaining why errors occur and providing specific techniques for improvement

8. Using effective questioning techniques to assess student understanding and guide them to discover relationships between system failures and appropriate responses

Student Actions

The student (or evaluator acting as student) will:

1. Participate in emergency scenario analysis by identifying symptoms, determining appropriate responses, and explaining reasoning

2. Practice emergency checklist procedures demonstrating proper prioritization between immediate actions and checklist items

3. Demonstrate understanding of vibration analysis by correlating different frequency vibrations with potential component problems

4. Ask relevant questions about aircraft-specific systems and emergency procedures

5. Participate in risk management discussions by identifying potential hazards and proposing mitigation strategies

6. Practice error recognition and correction through scenario-based exercises

Completion Standards

The CFI candidate successfully completes this lesson when they demonstrate the ability to:

1. Teach emergency recognition and response procedures for at least four different systems or equipment malfunctions as specified in HI.XIII.H.S1, including powerplant, electrical, flight instruments, pitot-static, electronic displays, landing gear, flight controls, or hydraulic systems

2. Demonstrate proper checklist usage during emergency procedures, showing appropriate prioritization of immediate action items versus time-available checklist items per HI.XIII.H.S2

3. Effectively analyze and correct common errors related to emergency procedures through clear explanation and positive instructional techniques per HI.XIII.H.S3

4. Incorporate risk management principles throughout instruction, specifically addressing startle response, checklist usage, task prioritization, and undesired aircraft states

5. Use effective instructional techniques including appropriate analogies, systematic presentation, and student engagement methods

6. Demonstrate comprehensive knowledge of helicopter-specific emergency procedures, vibration analysis, and fire/smoke response protocols

The instruction must meet the practical test standards for task HI.XIII.H, with the CFI candidate showing competency in both subject matter knowledge and instructional ability throughout the lesson presentation.