Operation of Systems

Objective

Upon completion of this lesson, the student will demonstrate knowledge and operation of helicopter systems in accordance with FAA-S-ACS-15 PH.I.G. The student will:

1. Explain the operation and function of all helicopter systems listed in PH.I.G.K1a through K1k
2. Identify indications of system abnormalities or failures and describe appropriate management procedures (PH.I.G.K2)
3. Demonstrate proper operation of at least three helicopter systems using appropriate checklists (PH.I.G.S1, PH.I.G.S2)
4. Apply risk management principles for system malfunction detection, failure management, and automated system monitoring (PH.I.G.R1, R2, R3)

Content

Flight Controls, Trim, and Stability Control (PH.I.G.K1a)

Flight control systems in helicopters are fundamentally different from fixed-wing aircraft. The cyclic controls pitch and roll through the swashplate mechanism, changing the angle of attack of individual rotor blades as they rotate. Think of it like tilting a dinner plate - the rotor disc tilts in the direction you move the cyclic.

The collective controls the pitch angle of all main rotor blades simultaneously, directly affecting lift. Anti-torque pedals control the pitch of the tail rotor blades to counteract main rotor torque and provide directional control.

Many modern helicopters include hydraulic-boosted flight controls per 14 CFR 27.143 or 29.143. These systems reduce control forces and improve handling qualities. Force trim systems, when installed, maintain control position without continuous pilot input.

Stability augmentation systems (SAS) or autopilot systems provide artificial stability. These automated systems require continuous monitoring per PH.I.G.R3, as failure can result in unexpected control responses.

Powerplant Systems (PH.I.G.K1b)

Helicopter powerplants are typically turboshaft engines or reciprocating engines. Turbine engines operate on the Brayton cycle, compressing air, adding fuel, igniting the mixture, and extracting energy through turbine stages.

Engine systems include:

• Fuel control units (FCU) or FADEC systems
• Oil systems for lubrication and cooling
• Air intake and filtration systems
• Exhaust systems with infrared suppressors on some models
• Engine monitoring systems displaying critical parameters

Power available decreases with altitude and temperature. Understanding power curves and limitations prevents exceeding engine capabilities, especially during high/hot/heavy operations.

Main Rotor and Anti-torque Systems (PH.I.G.K1c)

The main rotor system generates lift and thrust. Articulated rotor systems use hinges allowing blade flapping, lead/lag, and feathering. Semi-rigid systems use a teetering hinge. Rigid rotor systems flex at the blade root.

The swashplate translates pilot inputs into rotor blade pitch changes. The stationary swashplate connects to flight controls, while the rotating swashplate connects to pitch links on each blade.

Anti-torque systems counteract main rotor torque. Conventional tail rotors use variable pitch blades. Fenestron systems use a shrouded multi-blade fan. NOTAR systems use air circulation and directional thrust.

Transmission and Drive Systems (PH.I.G.K1d)

The main transmission reduces engine RPM to optimal rotor RPM while providing power to accessories. Typical ratios range from 6:1 to 15:1 depending on the helicopter.

Drive shafts connect the engine to the main transmission and tail rotor. These systems include:

• Engine-to-transmission drive coupling
• Tail rotor drive shaft with intermediate gearboxes on longer helicopters
• Freewheeling units allowing autorotation if engine fails
• Chip detectors monitoring for metal contamination

Transmission oil temperature and pressure are critical parameters requiring constant monitoring per PH.I.G.R1.

Fuel, Oil, and Hydraulic Systems (PH.I.G.K1e)

Fuel systems must provide uninterrupted flow during all flight attitudes per 14 CFR 27.955. Components include:

• Fuel tanks with baffles and pumps
• Fuel filters and flow indicators
• Fuel quantity indicating systems
• Emergency fuel shutoff valves

Oil systems lubricate and cool engine and transmission components. Synthetic oils are common in turbine applications due to temperature requirements.

Hydraulic systems, when installed, boost flight controls and operate landing gear, brakes, or cargo hooks. Typical system pressure is 1,000-3,000 PSI. Hydraulic failure requires immediate recognition and appropriate emergency procedures.

Avionics Systems (PH.I.G.K1f)

Modern helicopters utilize glass cockpit displays, GPS navigation, and digital flight management systems. These automated systems require active monitoring per PH.I.G.R3.

Communication radios operate in VHF bands (118.000-136.975 MHz) per 14 CFR 87. Navigation equipment includes GPS, VOR, and ADF systems where installed.

Transponder systems operating per 14 CFR 91.215 provide aircraft identification and altitude information to ATC radar systems.

Landing Gear, Brakes, and Steering Systems (PH.I.G.K1g)

Skid-equipped helicopters land on tubular skids with cross-tubes. Ground handling wheels may be installed for hangar movement.

Wheeled helicopters include:

• Fixed or retractable landing gear
• Anti-skid brake systems
• Wheel brakes operated by toe brakes or hand brake
• Steering systems for ground operations

Float-equipped helicopters for water operations include emergency flotation systems and water rudders for surface maneuvering.

Electrical Systems (PH.I.G.K1h)

Helicopter electrical systems typically operate at 14 or 28 volts DC. Components include:

• Engine-driven alternator or generator
• Battery for emergency power and engine starting
• Essential and non-essential bus systems
• Circuit breakers and protection devices
• External power receptacles for ground operations

Electrical system failures require load shedding and emergency procedures per the applicable checklist.

Pitot-Static and Flight Instruments (PH.I.G.K1i)

The pitot-static system provides pressure references for airspeed and altimeter indications per 14 CFR 27.1323. Helicopter pitot-static systems account for rotor downwash effects on accuracy.

Flight instruments include:

• Airspeed indicator with limitations marked
• Altimeter with barometric correction
• Vertical speed indicator
• Attitude and heading reference systems (AHRS)
• Engine instruments monitoring critical parameters

Vacuum or pressure systems, when installed, operate gyroscopic instruments. Many modern helicopters use electronic flight displays eliminating vacuum requirements.

Environmental Systems (PH.I.G.K1j)

Environmental systems maintain cabin comfort and window clarity:

• Heating systems using engine bleed air or exhaust heat exchangers
• Air conditioning systems in larger helicopters
• Ventilation systems providing fresh air circulation
• Anti-fog and defrost systems for windows

Cabin altitude and pressurization systems are rare in helicopters due to typical operating altitudes below 10,000 feet.

Anti-icing and Deicing Systems (PH.I.G.K1k)

Helicopters operating in known icing conditions require certified anti-ice or deice systems per 14 CFR 27.1419. Systems include:

• Engine inlet anti-ice using hot air
• Main rotor blade deice using electrothermal elements
• Pitot heat for static system protection
• Windshield anti-ice systems

Carburetor heat, when applicable on reciprocating engines, prevents ice formation in the induction system. Application reduces power and enriches the mixture.

System Abnormalities and Failures (PH.I.G.K2)

System malfunctions present through various indications:

• Caution and warning lights
• Abnormal gauge readings
• Unusual sounds, vibrations, or smells
• Changes in flight characteristics

Emergency procedures follow a standard format: recognize, analyze, take appropriate action, and land as soon as practical or immediately if required. Always consult the appropriate emergency checklist for specific procedures.

Risk Management (PH.I.G.R1, R2, R3)

Detection of system malfunctions (PH.I.G.R1) requires continuous monitoring of all systems during flight. Scan instruments regularly and be alert for any unusual indications or changes in helicopter performance.

Management of system failures (PH.I.G.R2) follows established priorities: maintain aircraft control, analyze the malfunction, take corrective action per checklist, and plan for appropriate landing. Never ignore warning indications or attempt flight with known system failures unless specifically authorized by emergency procedures.

Monitoring automated systems (PH.I.G.R3) requires understanding what the system is doing and being prepared to take manual control if necessary. Automation can fail, and pilots must maintain proficiency in manual operation of all systems.

Schedule

Equipment

Required References:

• FAA-S-ACS-15 Private Pilot Helicopter Airman Certification Standards
• FAA-H-8083-21B Rotorcraft Flying Handbook
• Aircraft-specific Pilot’s Operating Handbook (POH)
• Aircraft-specific maintenance manual excerpts
• 14 CFR Parts 27, 29, 61, 91

Materials:

• Training helicopter with operable systems
• Aircraft checklists (normal and emergency)
• System diagrams and cutaway models
• Whiteboard or flip chart
• Flashlight for instrument illumination

Visual Aids:

• Helicopter system component charts
• Engine and transmission cutaway models
• Rotor system demonstration models
• Electrical system schematic diagrams

Instructor Actions

1. Brief the lesson objectives and explain how system knowledge relates to safe helicopter operation and ACS requirements
2. Position student at helicopter controls and demonstrate location and operation of all flight control systems
3. Start helicopter engine following checklist procedures while explaining each step and monitoring requirements
4. Demonstrate engine parameter monitoring, explaining normal ranges and abnormal indications per POH limitations
5. Show main rotor and tail rotor system operation during different flight control inputs
6. Point out transmission and drive system monitoring equipment, explaining chip detector indications and oil pressure/temperature parameters
7. Demonstrate fuel system operation including fuel pumps, quantity indications, and fuel management procedures
8. Show hydraulic system operation (if equipped) including system pressure indications and backup procedures
9. Operate avionics systems including radios, navigation equipment, and transponder per checklist procedures
10. Demonstrate electrical system management including alternator monitoring and load management
11. Show landing gear operation (if retractable) or explain skid/float systems as applicable
12. Operate environmental systems including heating, ventilation, and anti-ice systems where installed
13. Present examples of system abnormal indications using POH emergency procedures
14. Guide student through operation of at least three different systems using appropriate checklists
15. Quiz student on system operation and emergency procedures to verify understanding
16. Debrief lesson performance and provide specific feedback on areas for improvement

Student Actions

1. Listen to instructor briefing and ask questions about lesson objectives and ACS requirements
2. Identify location and function of all flight control components when prompted by instructor
3. Follow along with engine start checklist and identify key monitoring parameters
4. Point out normal engine parameter ranges on instruments when requested
5. Observe rotor system operation and explain the relationship between control inputs and rotor response
6. Locate transmission monitoring equipment and state normal operating parameters
7. Demonstrate fuel system operation including pump switches and quantity checks
8. Operate hydraulic system controls (if applicable) and identify backup procedures
9. Use avionics equipment to tune radios, navigate, and set transponder codes per instructor guidance
10. Demonstrate electrical system monitoring and explain load management principles
11. Operate applicable landing gear or explain ground handling procedures for skids/floats
12. Use environmental system controls and explain their operation
13. Identify abnormal system indications when presented by instructor and state appropriate corrective actions
14. Independently operate three different helicopter systems using appropriate checklists
15. Answer instructor questions about system operation and emergency procedures
16. Participate in lesson debrief and ask questions about areas of confusion

Completion Standards

The student demonstrates satisfactory knowledge and skill when they can:

Knowledge Standards (FAA-S-ACS-15 PH.I.G.K1-K2):

• Correctly explain the operation and function of all helicopter systems listed in PH.I.G.K1a through K1k with 90% accuracy
• Identify at least five different system abnormal indications and state the appropriate corrective action for each
• Describe proper procedures for managing system failures including priority of actions and checklist usage

Risk Management Standards (FAA-S-ACS-15 PH.I.G.R1-R3):

• Demonstrate systematic instrument scanning techniques for early malfunction detection
• Explain decision-making process for managing system failures including when to land immediately versus continuing flight
• Describe proper monitoring techniques for automated systems and backup procedures for system failures

Skill Standards (FAA-S-ACS-15 PH.I.G.S1-S2):

• Successfully operate at least three different helicopter systems from the K1a through K1k list using proper procedures
• Complete all system operations using appropriate checklists without omitting required steps
• Demonstrate smooth, deliberate operation of all systems without creating unsafe conditions

Overall Performance:

• Maintain professional demeanor and safety awareness throughout all system operations
• Complete all required actions within normal time parameters for each system
• Show competence and confidence in system operation that meets Private Pilot Helicopter certification standards per FAA-S-ACS-15 PH.I.G