Approach and Landing with One Engine Inoperative (OEI) (Simulated) (Multiengine Helicopter Only)

Objective

Upon completion of this lesson, the CFI candidate will demonstrate the ability to teach approach and landing with one engine inoperative (OEI) in a multiengine helicopter by explaining all elements of the procedure, conducting risk assessment, and demonstrating proper instructional techniques. The candidate will meet all requirements of ACS task HI.XIII.C and effectively communicate emergency approach concepts to student pilots.

Content

Elements of Approach and Landing with One Engine Inoperative (HI.XIII.C.K1)

Power Available vs. Power Required in OEI Operations Think of OEI operations like driving a car with half the cylinders dead—you can still move, but everything changes. In a twin-engine helicopter, losing one engine creates an immediate power deficit that affects every aspect of flight performance.

Key elements include:

• Height-Velocity (H-V) diagram considerations: The dead man’s curve becomes your enemy. We must stay within the crosshatched area or accept the risks of the avoid area
• Critical decision point: The moment when continuing forward becomes safer than attempting to land straight ahead
• Autorotational energy management: Unlike single-engine helicopters, you have some power available to cushion the approach
• Configuration management: Gear, flaps, and other systems affect drag and performance
• Power margin awareness: Operating at or near maximum continuous power limits

Teaching Point: Use the analogy of a wounded bird—it can still fly, but it must choose its landing spot carefully and approach more gradually.

Effects of Atmospheric Conditions on Emergency Approach and Landing (HI.XIII.C.K2)

Density Altitude Impact High density altitude compounds OEI challenges exponentially. Hot, high, humid, and heavy conditions reduce the already-limited power available from the operating engine.

Critical factors:

• Temperature effects: For every 10°C above standard, expect 3-4% power loss
• Pressure altitude: Higher elevation reduces power available
• Humidity: Reduces air density, decreasing rotor efficiency
• Weight considerations: Must be managed aggressively in OEI conditions

Wind Effects

• Headwind: Extends glide distance, allows steeper approach angles
• Tailwind: Reduces glide distance, requires shallower approaches
• Crosswind: Complicates directional control with reduced anti-torque authority
• Turbulence: Increases workload when precision is most critical

Stabilized Approach Concepts (HI.XIII.C.K3)

The Four-Point Check A stabilized approach in OEI conditions requires constant monitoring:

1. Airspeed: Maintain best glide or manufacturer-recommended approach speed
2. Descent rate: Steady, controlled rate appropriate for conditions
3. Flight path: Clear of obstacles with adequate safety margins
4. Configuration: Proper gear/flap settings for landing

Energy Management Philosophy “Altitude is money in the bank, airspeed is cash in your pocket.” In OEI approaches, we’re managing a limited energy budget. Height gives us options; airspeed gives us control authority.

Approach and Landing Profiles and Aircraft Configuration (HI.XIII.C.K4)

Profile Selection Based on Conditions Three primary profiles:

1. Shallow approach: When landing area permits, reduces sink rate
2. Normal approach: Balanced profile for most conditions
3. Steep approach: When obstacles dictate, requires careful power management

Configuration Management

• Landing gear: Deploy early to reduce last-minute workload
• Flaps/spoilers: Use manufacturer recommendations for drag configuration
• Collective: Smooth inputs to avoid over-torquing remaining engine
• Trim: Essential for reducing control forces during critical phases

Common Errors Related to This Task (HI.XIII.C.K5)

Critical Teaching Points for Error Recognition:

1. Fixation on failed engine: Students often become absorbed with restart procedures instead of flying the helicopter
2. Power mismanagement: Over-torquing the operating engine or failing to use available power effectively
3. Approach angle errors: Too steep (insufficient power to arrest descent) or too shallow (landing long)
4. Airspeed deviations: Flying too fast (reducing glide distance) or too slow (risking loss of control)
5. Directional control issues: Inadequate pedal inputs or overcorrection

Risk Management Considerations

Altitude, Wind, Terrain, Obstructions, and Available Landing Area Assessment (HI.XIII.C.R1) The AWTOLA acronym helps systematic evaluation:

• Altitude: Sufficient height for approach profile selected
• Wind: Direction and velocity effects on approach path
• Terrain: Slope, surface conditions, and escape routes
• Obstructions: Power lines, trees, buildings in approach path
• Landing Area: Size, surface, and approach/departure options

Flight Path Planning and Following (HI.XIII.C.R2) “Plan the flight, fly the plan, but be ready to adapt.” Establish clear visual references and backup plans. The approach path should provide multiple decision points for go-around or landing site changes.

Collision Hazards (HI.XIII.C.R3) Declare emergency status immediately. Emergency aircraft have priority, but other traffic may not see or hear you. Maintain visual scanning while managing the emergency—delegate radio calls when possible.

Task Prioritization and Situational Awareness (HI.XIII.C.R4) Use the “AVIATE, NAVIGATE, COMMUNICATE” priority system. In OEI situations, flying the helicopter takes precedence over checklist completion or radio calls. Maintain awareness of energy state and options throughout the approach.

Schedule

Equipment

Required References:

• Helicopter Flying Handbook (FAA-H-8083-21B), Chapter 11
• Aviation Instructor’s Handbook (FAA-H-8083-9), Chapters 4-6
• Aircraft Flight Manual/Pilot’s Operating Handbook
• Commercial Pilot ACS (FAA-S-ACS-29)

Materials:

• Whiteboard/markers for flight path diagrams
• H-V diagram examples for specific aircraft
• Checklist examples (emergency and normal)
• Visual aids showing approach profiles

Visual Aids:

• OEI approach profile diagrams
• H-V diagram overlays
• Wind triangle calculations
• Landing site selection criteria chart

Instructor Actions

The CFI candidate will:

1. Explain OEI approach procedures using clear analogies and technical accuracy, demonstrating understanding of power limitations and performance degradation
2. Demonstrate approach planning by walking through altitude, wind, terrain, obstruction, and landing area assessment using realistic scenarios
3. Show stabilized approach techniques through chair flying exercises, emphasizing the four-point check and energy management principles
4. Identify and correct common errors by presenting typical student mistakes and explaining appropriate corrective actions
5. Conduct risk assessment procedures showing systematic evaluation of emergency approach factors
6. Simulate radio communications demonstrating appropriate emergency calls and coordination
7. Explain checklist usage showing when and how to complete emergency procedures without compromising flight safety
8. Demonstrate teaching techniques specific to emergency procedures, including stress management and priority setting

Student Actions

The student (DPE) will:

1. Ask questions about OEI performance limitations and approach planning considerations
2. Present scenarios requiring risk assessment and decision-making during simulated emergencies
3. Evaluate teaching effectiveness by observing clarity of explanations and demonstration techniques
4. Challenge understanding with “what if” questions about atmospheric conditions and configuration changes
5. Assess error recognition by presenting common student mistakes for correction
6. Observe instructional techniques for emergency procedure training and stress management
7. Verify completion standards against ACS requirements throughout the lesson

Completion Standards

The CFI candidate successfully completes HI.XIII.C when able to:

1. Explain all elements of OEI approach and landing procedures with technical accuracy and appropriate teaching techniques
2. Demonstrate systematic risk assessment covering altitude, wind, terrain, obstructions, and landing area considerations (HI.XIII.C.R1)
3. Show proper flight path planning and explain how to follow planned approaches to selected landing areas (HI.XIII.C.R2, HI.XIII.C.S4)
4. Teach power management techniques for maintaining operating engine within OEI limits (HI.XIII.C.S1)
5. Explain approach profile standards including altitude ±100 feet, airspeed ±10 knots, and heading ±5° tolerances (HI.XIII.C.S2)
6. Demonstrate radio communication procedures appropriate for emergency situations (HI.XIII.C.S3)
7. Show checklist management techniques that maintain flight safety priorities (HI.XIII.C.S5)
8. Explain directional control techniques including crosswind correction throughout approach and landing (HI.XIII.C.S6)
9. Demonstrate resource management using SRM/CRM principles as appropriate (HI.XIII.C.S7)
10. Identify and correct common errors related to OEI approach and landing operations (HI.XIII.C.S8)
11. Use effective teaching techniques appropriate for emergency procedure instruction, including stress management and clear communication under pressure

Performance meets ACS standards when the candidate demonstrates comprehensive understanding of OEI approach procedures and shows ability to effectively teach these critical emergency skills to student pilots.