Operational Requirements – XI. Emergency Operations, Task C: 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 per ACS task HI.18.I. The candidate will explain operational requirements, risk management considerations, and demonstrate proper instructional techniques for this critical emergency procedure while maintaining appropriate safety margins and altitude requirements.

Content

Fundamentals of Instructing Application

This lesson applies the learning theory principle of building complex skills from foundational knowledge. Emergency procedures require both cognitive understanding and psychomotor skill development. Use the demonstration-performance method with clear explanation of each step, allowing the student to progress from observation to guided practice to independent performance.

OEI Approach and Landing Overview

One Engine Inoperative (OEI) approaches are critical emergency procedures that every multiengine helicopter pilot must master. Unlike single-engine helicopters where engine failure typically results in autorotation, multiengine helicopters offer continued powered flight capability with reduced performance.

Key Operational Requirements:

• Minimum altitude to initiate: 1,000 feet AGL (ACS requirement)
• Mandatory preflight briefing regarding simulated failure expectations
• Only conducted in actual multiengine helicopters during practical tests
• Requires thorough understanding of aircraft limitations and performance

Performance Considerations

When one engine fails in a multiengine helicopter, several critical factors immediately change:

• Available power reduced by approximately 50%
• Increased power demand on operating engine
• Asymmetric thrust conditions requiring compensation
• Reduced climb performance or inability to climb
• Increased fuel consumption on operating engine
• Potential for exceeding operating engine limitations

Power Available vs. Power Required: Think of it like driving a car up a hill with half your engine cylinders missing - you might maintain speed on level ground, but that hill becomes much more challenging. Similarly, a helicopter on one engine may hover at light weights but struggle with any additional power demands.

Altitude and Energy Management

The 1,000-foot AGL minimum exists for critical safety reasons:

• Provides adequate altitude for power/performance assessment
• Allows time for proper emergency procedures completion
• Ensures sufficient height for transition to autorotation if second engine fails
• Permits safe abort of approach if conditions become unsafe

Energy management becomes paramount - altitude is your insurance policy. Convert altitude to controlled descent rather than attempting to maintain level flight if power is insufficient.

Risk Management Considerations

Pre-flight Briefing Requirements: The evaluator must conduct a comprehensive briefing covering:

• Altitude and location where failure will be simulated
• Method of simulating engine failure (throttle reduction, etc.)
• Student’s expected immediate responses
• Abort criteria and procedures
• Communication protocols during the exercise

Safety Considerations:

• Weather conditions must support safe OEI operations
• Landing area must be suitable for potentially steeper approaches
• Fuel quantity adequate for extended single-engine operations
• Aircraft weight and center of gravity within OEI limits
• Escape routes planned in case of actual second engine failure

OEI Approach Technique

Initial Response to Engine Failure:

1. Maintain rotor RPM within limits
2. Adjust collective to maintain airspeed and rate of descent
3. Apply anti-torque pedal to maintain heading
4. Complete engine failure checklist items
5. Assess power available vs. power required

Approach Profile:

• Steeper than normal approach angle typically required
• Airspeed management critical - too fast wastes energy, too slow risks retreating blade stall
• Constant evaluation of power margins throughout approach
• Be prepared to enter autorotation if power becomes insufficient

Landing Technique:

• Plan for running landing if power insufficient for hover
• Use ground effect to advantage in final stages
• Minimize power demands through proper energy management
• Be prepared for immediate autorotation if remaining engine fails

Common Student Errors and Instructional Techniques

Error: Attempting to maintain normal approach profile Correction: Emphasize that OEI approaches are inherently different. Use the analogy of a glider - you must use the energy you have efficiently rather than fighting physics.

Error: Inadequate power management Correction: Teach continuous power margin assessment. Like checking your bank account before making a purchase - always know what power you have available.

Error: Poor decision making regarding continuation Correction: Establish clear “go/no-go” criteria before beginning the approach. If power margins become insufficient, autorotation is the safest option.

Schedule

Equipment

• FAA-S-ACS-29 (CFI Helicopter Airman Certification Standards)
• FAA-H-8083-4 (Helicopter Instructor’s Handbook)
• FAA-H-8083-21A (Helicopter Flying Handbook)
• Aircraft Flight Manual/Pilot’s Operating Handbook for multiengine helicopter
• Performance charts and limitations placards
• Sectional chart for area familiarization
• Whiteboard/presentation materials for performance concepts
• Timer for approach timing practice

Instructor Actions

The CFI candidate will:

• Explain the 1,000-foot AGL minimum altitude requirement and its safety basis, referencing ACS task HI.18.I
• Demonstrate proper pre-flight briefing techniques as required by ACS standards
• Use performance charts to illustrate power available vs. power required concepts
• Show proper risk assessment for OEI approach conditions
• Demonstrate the complete OEI approach sequence through chair flying while providing clear, step-by-step explanations
• Explain energy management principles using appropriate analogies
• Identify common student errors and demonstrate effective correction techniques
• Emphasize decision-making criteria for approach continuation vs. autorotation
• Show how to assess power margins throughout the approach
• Demonstrate proper landing technique variations based on available power

Student Actions

The evaluator (acting as student) will:

• Ask questions about altitude requirements and safety considerations
• Request clarification on power management techniques
• Simulate common student misconceptions about OEI performance
• Practice chair flying portions of the OEI approach sequence
• Demonstrate understanding of risk management factors
• Show comprehension of the pre-flight briefing requirements
• Practice explaining the relationship between power available and power required
• Demonstrate knowledge of when to abort the approach for autorotation

Completion Standards

The CFI candidate successfully completes this lesson when they demonstrate the ability to teach OEI approach and landing techniques per ACS task HI.18.I by:

• Accurately explaining the mandatory 1,000-foot AGL minimum altitude requirement for initiating OEI approaches
• Demonstrating comprehensive pre-flight briefing techniques that address simulated powerplant failure expectations
• Clearly explaining the performance limitations and capabilities of multiengine helicopters operating on one engine
• Effectively teaching energy management and approach profile modifications required for OEI operations
• Identifying and correcting common student errors in OEI approach technique
• Demonstrating proper risk assessment and decision-making criteria for approach continuation
• Showing competency in explaining when and how to transition from OEI approach to autorotation if necessary
• Using appropriate instructional techniques that build student understanding progressively from theory to application
• Maintaining instructional standards that ensure student competency in this critical emergency procedure