Approach with Loss of Primary Flight Instrument Indicators

Objective

The student will demonstrate understanding of primary flight instrument failure modes and decision-making processes required during IMC operations, and will safely conduct a complete non-precision instrument approach to MDA using partial panel (standby instruments) while managing single-pilot IFR workload, maintaining aircraft control within ACS standards, and communicating effectively with ATC. Upon completion, the student will meet the knowledge, risk management, and skill requirements of ACS IH.VIII.C and demonstrate proficiency in completing a non-precision approach per ACS IH.VI.A standards using only standby instruments.

ACS Task: IH.VIII.C — Approach with Loss of Primary Flight Instrument Indicators

Measurable Outcomes:

• Recognize and correctly identify primary flight instrument failures within 10 seconds of occurrence
• Properly advise ATC of reduced capability using standard phraseology
• Maintain helicopter control within ACS tolerances (±100 feet altitude, ±10° heading, ±10 knots airspeed) using standby instruments
• Complete a full non-precision approach to MDA using partial panel configuration
• Demonstrate effective single-pilot resource management under increased workload conditions

Content

Introduction

Loss of primary flight instruments during IMC operations represents one of the most serious emergencies an instrument-rated helicopter pilot can face. Unlike fixed-wing aircraft where autopilot systems can provide backup control, most training helicopters (R22, R44, Schweizer 300C) lack autopilot capability, making the single pilot wholly responsible for maintaining aircraft control while navigating, communicating, and making critical decisions under significantly increased workload. This lesson addresses the knowledge, risk management, and skills required to recognize instrument failures, maintain control using standby instruments, and safely complete an approach to landing or missed approach.

Regulatory Foundation

14 CFR §91.205(d) — Instrument flight rules equipment requirements mandate specific instruments for IFR operations:

• Airspeed indicator
• Attitude indicator (must have source of power separate from pitot-static system)
• Altimeter (sensitive)
• Clock with hours, minutes, seconds
• Heading indicator (gyroscopic or magnetic)
• Rate of turn indicator (turn coordinator or turn-and-slip)
• Slip-skid indicator
• Outside air temperature gauge
• Manifold pressure gauge (each altitude engine)
• Generator/alternator adequate electrical source

14 CFR §91.187 — Requirement for second altimeter system for operations above FL240 (rarely applicable to helicopters but demonstrates redundancy principle).

14 CFR §91.213 — Inoperative instruments and equipment: If primary flight instruments become inoperative during flight, the pilot must determine if continued IFR flight is legal and safe. The aircraft may no longer meet equipment requirements for IFR, making it technically illegal to continue in IMC to destination unless under emergency authority (§91.3).

AIM 5-5-11 — Includes guidance on advising ATC when aircraft capabilities are reduced due to equipment failure.

Primary Flight Instrument Systems (IH.VIII.C.K1, IH.VIII.C.K2)

Glass Cockpit Configurations

Primary Flight Display (PFD) Systems: Modern glass cockpit helicopters (G500H, Aspen, Garmin G500H TXi) integrate attitude, heading, altitude, airspeed, and vertical speed on a single electronic display. Common failure modes include:

• Complete PFD failure — Total loss of screen due to power failure, internal electronics failure, or software fault
• Partial display degradation — Red “X” through individual instruments (attitude, heading, altitude, airspeed) indicating sensor failure or invalid data
• AHRS failure — Attitude and Heading Reference System malfunction causes attitude and heading displays to flag as unreliable; other instruments may remain valid
• Air Data Computer (ADC) failure — Loss of altitude, airspeed, vertical speed; attitude and heading may remain valid
• GPS loss — In systems dependent on GPS for navigation data, loss affects map displays and GPS-based approaches but not basic flight instruments

Recognition methods:

• Red “X” symbols overlaying failed instruments
• Flashing warning messages (“ATTITUDE FAIL,” “AHRS FAIL,” “ADC FAIL”)
• Conflicting indications between PFD and standby instruments
• Erratic or frozen displays
• Complete screen blank or dim

Standby instruments in glass cockpit helicopters typically include:

• Standby attitude indicator (usually electric or vacuum-powered)
• Standby altimeter (pitot-static)
• Standby airspeed indicator (pitot-static)
• Magnetic compass

Correction procedures for PFD failure:

1. Immediately transition scan to standby instruments
2. Verify standby instruments are functioning (cross-check multiple sources)
3. Reduce workload by simplifying flight profile if possible
4. Declare reduced capability to ATC
5. Consider requesting surveillance approach (ASR) if available
6. Plan approach that minimizes complexity (non-precision vs. precision, radar vectors vs. procedure turn)

Steam Gauge Configurations (Traditional Six-Pack)

Attitude Indicator Failure: Most common primary instrument failure in steam gauge panels. Typically vacuum-powered in training helicopters.

Possible failure modes:

• Gradual precession causing erroneous bank/pitch indications (insidious failure)
• Tumbling during unusual attitudes beyond instrument limits
• Vacuum pump failure affecting both attitude indicator and heading indicator simultaneously
• Complete stoppage showing fixed attitude regardless of aircraft movement
• Power failure in electrically-driven instruments

Recognition:

• Compare attitude indicator with turn coordinator movement (if banking right, turn coordinator should show right turn)
• Cross-check against altimeter, airspeed, and vertical speed trends
• During straight-and-level flight, if attitude indicator shows bank but turn coordinator shows wings level, attitude indicator is suspect
• If airspeed increasing but attitude indicator shows level pitch, suspect nose-low attitude not reflected on indicator

Compensation techniques: Use turn coordinator, altimeter, airspeed indicator, and VSI for control:

• Turn coordinator provides bank/turn rate (standard rate = 3° per second, 2 minutes for 360°)
• Altimeter confirms pitch attitude (rising = nose up, falling = nose down)
• Airspeed confirms pitch attitude (decreasing = nose up, increasing = nose down)
• VSI provides immediate pitch trend information
• Manifold pressure combined with airspeed/VSI confirms power setting effectiveness

Heading Indicator Failure: Often fails simultaneously with attitude indicator in vacuum system failures.

Failure modes:

• Precession causing gradual heading error accumulation
• Complete stoppage
• Vacuum system failure
• Erratic rotation

Recognition and compensation:

• Cross-check with magnetic compass during wings-level, constant-speed flight
• Use turn coordinator to maintain turns and calculate heading changes (standard rate turn: 3° per second)
• In straight flight, use magnetic compass for primary heading reference (account for acceleration/deceleration errors: ANDS — Accelerate North, Decelerate South; and turning errors: UNOS — Undershoot North, Overshoot South)

Altimeter Failure:

Failure modes:

• Pitot-static system blockage (ice, insects, cover left on)
• Internal mechanism failure
• Leak in static system

Recognition:

• Altimeter reading remains constant during known climbs/descents
• Conflicting reading between encoding altimeter and ATC-reported altitude
• VSI shows climb/descent but altimeter frozen

Compensation:

• Use airspeed and VSI trends to maintain altitude (in level flight, constant airspeed and zero VSI indicate altitude hold)
• Request altitude information from ATC radar
• Use GPS altitude as backup reference (note: GPS altitude is MSL based on ellipsoid, may differ 50-100 feet from barometric altitude; not approved for IFR)

Airspeed Indicator Failure:

Failure modes:

• Pitot tube blockage (most common)
• Static port blockage
• Line disconnection
• Internal mechanism failure

Recognition:

• Airspeed does not change with power or pitch changes
• Conflicting indication between power setting, pitch attitude, and indicated airspeed

Compensation:

• Use manifold pressure, attitude, and altitude performance for known configurations
• Memorize power settings for standard configurations: cruise, approach speed, climb
• Example (R44): 23” MP = approximately 90 KIAS cruise; 20” MP = approximately 60 KIAS approach speed
• VSI and altimeter trends confirm whether speed is appropriate for phase of flight

Turn Coordinator Failure:

Failure modes:

• Electric power failure
• Internal gyro failure
• Less common in training helicopters with electric turn coordinators

Recognition:

• Instrument shows wings level during known turns
• No precession or movement during maneuvering

Compensation:

• Use heading indicator changes (assuming heading indicator is functioning) to control turn rate
• Timed turns using clock: standard rate = 3° per second (20 seconds for 60° turn)
• Magnetic compass for heading reference in wings-level flight

Vertical Speed Indicator Failure:

Failure modes:

• Static system blockage
• Internal mechanism failure
• Line leak

Recognition:

• VSI shows zero or unchanging rate during known climbs/descents
• Lag is excessive (normal VSI has 6-9 second lag)

Compensation:

• Use altimeter trend for pitch control
• Use airspeed trend (in level flight, increasing airspeed = descending; decreasing airspeed = climbing)
• Use attitude indicator pitch indications more precisely

Vacuum System Failure (Steam Gauge Aircraft)

Most training helicopters with steam gauges use vacuum-driven attitude and heading indicators. Vacuum system failure causes simultaneous loss of both instruments, representing the most challenging partial panel scenario.

Indications of vacuum failure:

• Low vacuum reading on gauge (normal = 4.5 to 5.5 inches Hg)
• Attitude indicator begins erratic precession then winds down
• Heading indicator begins rapid precession
• May be accompanied by unusual smell if vacuum pump fails mechanically

Immediate actions:

1. Transition to turn coordinator, altimeter, airspeed, VSI, and compass
2. Establish straight-and-level using turn coordinator (wings level) and altimeter/airspeed (pitch)
3. Note last reliable heading before heading indicator becomes useless
4. Reduce workload immediately
5. Advise ATC of partial panel operations

Risk Management Considerations

IH.VIII.C.R1: Use of Secondary Flight Displays When Primary Displays Have Failed

Glass cockpit scenarios: When PFD fails, transition immediately to standby instruments. Critical considerations:

• Scan transition delay — Pilots accustomed to glass displays often experience 5-10 second transition period to standby instrument scan; this delay can cause altitude/heading deviations in IMC
• Standby instrument locations — Usually positioned to right side of PFD or lower panel; practice locating and scanning before failure occurs
• Verify standby instrument accuracy — Before complete PFD failure trust, cross-check standby instruments against PFD in VMC; some standby systems have separate pitot-static sources
• Workload increase — Standby instruments require more intensive scan than integrated PFD; anticipate 30-40% workload increase
• MFD backup — Some installations allow basic attitude information on MFD (multifunction display); know your system’s reversionary mode procedures

Steam gauge scenarios: When primary instruments fail, remaining instruments become “secondary displays”:

• Turn coordinator limitations — Shows rate of turn and slip/skid only; does not provide pitch information; requires mental computation to estimate bank angles
• Magnetic compass limitations — Accurate only in wings-level, constant-speed flight; turning errors (UNOS) and acceleration errors (ANDS) require compensation
• Increased scan intensity — Partial panel requires more rapid, disciplined scan across 5-6 instruments instead of centralized attitude indicator reference
• Higher workload — Studies show partial panel operations increase pilot workload 40-60%; compounded in single-pilot helicopters

Risk mitigation strategies:

• Immediately reduce speed if practicable (approach speed provides better control margins, more time to scan)
• Request radar vectors to simplify navigation workload
• Brief standby instrument locations and emergency scan pattern before every IFR flight
• Consider requesting ASR (airport surveillance radar) approach if available — controller provides all heading and altitude guidance
• If two pilots are aboard, clearly divide duties: flying pilot focuses exclusively on aircraft control; non-flying pilot handles all radio work and navigation

IH.VIII.C.R2: Maintaining Helicopter Control

Loss of primary instruments significantly increases risk of spatial disorientation and loss of control. Helicopters are inherently less stable than airplanes and require constant control inputs.

Control priorities (Aviate, Navigate, Communicate):

1. Aviate first — Aircraft control is paramount; let altitude/heading deviate slightly rather than overcontrol and induce unusual attitude
2. Trim workload — In helicopters with force trim systems (e.g., R44 IFR), use force trim to reduce cyclic pressures; allows smoother partial panel control
3. Limit maneuvering — Avoid steep turns, high descent rates, and abrupt control inputs; standard-rate turns maximum; 500 FPM descents preferred
4. Airspeed discipline — Maintain approach speed or higher; slower speeds reduce control damping and increase workload
5. Configuration management — Avoid changing helicopter configuration (power settings, airspeed) unless necessary; each change requires new control scan validation

Helicopter-specific control considerations:

• Collective-throttle correlation — In non-governor-equipped helicopters (most Schweizer 300C trainers), coordination of collective and throttle becomes more difficult when attitude reference is degraded; maintain strict RPM discipline
• Tail rotor control — Loss of heading reference makes directional control more challenging; pedal inputs must be deliberate and cross-checked against turn coordinator and compass
• Power settling with power (vortex ring state) risk — If disoriented and inadvertently descending, increasing collective without forward airspeed can induce settling with power; if uncertain of attitude, shallow approach descent rates (300-500 FPM) with forward airspeed minimize this risk
• Single-pilot workload — No autopilot; pilot must hand-fly entire approach while managing radios, navigation, and emergency decision-making

Control deviation recognition:

• Set and verify known pitch attitude (e.g., approach descent: specific power setting should yield specific airspeed and descent rate)
• If any parameter begins drifting (altitude increasing, airspeed decreasing), make immediate small corrections
• Use verbal callouts if alone (“Altitude deviation, pitch forward,” “Right turn developing, level wings”)
• Expect larger tolerances: ±100 feet altitude, ±10° heading, ±10 knots airspeed are ACS standards but under partial panel conditions, staying within ±150 feet and ±15° initially is acceptable; refine as scan stabilizes

IH.VIII.C.R3: Distractions, Task Prioritization, Loss of Situational Awareness, or Disorientation

Primary instrument failure is a critical distraction that can rapidly lead to disorientation, especially in single-pilot IMC operations.

Distraction management:

• Immediate recognition — Train to recognize failures within 10 seconds; prolonged use of failed instrument increases disorientation risk exponentially
• Verbalize failure — State aloud “Attitude indicator failed, transitioning to partial panel” to cement cognitive awareness
• Ignore failed instruments — Cover failed instrument with approach plate, sticky note, or mentally discipline yourself not to include it in scan; failed instruments provide compelling but false information
• Simplify flight plan — If IMC continuation is necessary, immediately request simplest routing: vectors to final, no procedure turn approach, extended final

Task prioritization: Use the 5 Ps of single-pilot resource management:

1. Plan — Immediate plan: maintain aircraft control, transition to partial panel scan
2. Plane — Assess aircraft: which instruments failed, which remain reliable, fuel status, aircraft control margins
3. Pilot — Assess self: workload manageable? Disorientation developing? Need to declare emergency?
4. Passengers — Brief passengers to remain silent unless emergency; reduce distractions
5. Programming — Delay all GPS/navigation reprogramming unless critical; aviate first

Task hierarchy during partial panel approach:

1. Aircraft control (continuous) — Maintain altitude ±100 feet, heading ±10°, airspeed ±10 knots
2. Navigation (periodic) — Verify on course; use NAV radio, GPS, and ATC for situational awareness
3. Communication (as needed) — Advise ATC of partial panel, request assistance, acknowledge clearances

Loss of situational awareness: Indicators you are losing situational awareness:

• Uncertain of aircraft position relative to approach course
• Uncertain of aircraft altitude trend (climbing, descending, level)
• Fixating on one instrument while others deviate
• Behind the helicopter (reacting to deviations rather than maintaining parameters)

Mitigation:

• Use all available resources: ask ATC for position, altitude confirmation
• Cross-check: “I’m showing 3,000 feet, does that match your radar?”
• Verbalize situational updates: “5 miles from JAMID, descending to 2,400”
• If situational awareness is completely lost and aircraft control is becoming marginal, declare emergency and request ASR approach or vectors to VMC

Spatial disorientation recognition:

• Leans: vestibular system conflicts with instrument indications
• Graveyard spiral: feel of coordinated turn interpreted as wings level; pilot pulls back increasing bank
• Somatogravic illusion: acceleration feels like pitch up; pilot pitches down
• In helicopters: translating tendency and tail rotor thrust can cause unusual proprioceptive feedback

Response to disorientation:

• Trust instruments completely — This is foundational instrument flying but critical during partial panel
• Verbalize: “I feel like I’m turning left but turn coordinator shows wings level; I trust the instruments”
• Small control inputs; avoid overcontrolling based on vestibular feedback
• If disorientation is severe and controllability is in question: declare emergency, request ASR approach or no-gyro vectors

ATC Communications and Pilot Decision-Making (IH.VIII.C.K1, IH.VIII.C.S1)

Recognizing and advising ATC of reduced capability:

When primary flight instruments fail in IMC:

1. Maintain control first — Stabilize helicopter in straight-and-level or established descent before making radio calls
2. Notify ATC immediately after control is established — ATC can provide assistance (vectors, altitude confirmations, surveillance approaches)
3. Use standard phraseology — “Approach, Helicopter 12345, we’ve lost our primary attitude indicator, request vectors for the approach and priority handling”
4. Declare emergency if necessary — 14 CFR §91.3(b) authorizes deviation from any regulation to meet an emergency; partial panel in IMC may justify emergency authority even if aircraft control is maintained

Phraseology examples:

• “New York Approach, Helicopter 4582X, we have a failed attitude indicator, partial panel, request vectors to final approach course and extended final for the ILS Runway 4.”
• “Center, Helicopter 739DH, we’ve lost our primary flight display, operating partial panel on standby instruments, request priority handling and ASR approach if available.”
• “Tower, Helicopter 123AB, primary vacuum system failure, we are partial panel, need to keep the approach tight, is the field VFR?” (Requesting weather update to determine if VMC descent is option)

Unable to comply with clearances: ATC may issue clearances that are unsafe or impractical under partial panel operations:

• Holding patterns — High workload; if unable to safely comply: “Unable to accept holding, partial panel operations, request vectors or expect delay time”
• Procedure turns — High maneuvering workload; request: “Request vectors to final in lieu of procedure turn, partial panel”
• Complex arrivals/departures — Request simpler routing: “Unable RNAV STAR, partial panel, request vectors”
• Altitude/heading changes — If task saturation is high and additional changes would compromise control: “Unable immediate, need 2 minutes to stabilize partial panel”

Decision-making: Continue or divert?

Critical decision: Continue IFR to destination or divert to VMC?

Factors favoring continuation:

• Standby instruments are verified functional
• Pilot is proficient in partial panel operations
• Destination weather is at or above approach minimums with good trends
• Approach is non-precision, relatively simple (RNAV, VOR)
• ATC can provide radar vectors and surveillance assistance
• Fuel is adequate for approach and missed approach with reserve

Factors favoring diversion to VMC:

• Pilot is uncomfortable with partial panel proficiency
• Destination weather is marginal (at minimums) or deteriorating
• Multiple approaches may be required
• Nearest VMC is within range with adequate fuel
• Approach is complex (procedure turn, multiple step-downs)
• Additional systems are suspect (e.g., vacuum failure may indicate alternator problems developing)

Legal considerations:

• With primary flight instruments inoperative, the aircraft may not meet 14 CFR §91.205(d) equipment requirements for IFR flight
• Pilot may continue under emergency authority (§91.3) but should advise ATC
• After landing, §91.3(c) requires written report to FAA if emergency authority was invoked and FAA requests it

Partial Panel Approach Procedures (IH.VIII.C.S2)

The skill element requires completing a non-precision approach using partial panel configuration to the same standards as ACS Area of Operation VI, Task A (Non-Precision Approach).

Standard non-precision approach completion standards (from ACS IH.VI.A):

• Accomplish the appropriate checklist items
• Establish two-way communications with ATC, comply with clearances and instructions
• Select, identify, and confirm the operational status of navigation equipment
• Comply with the minimum safe/sector altitudes
• Establish the appropriate helicopter configuration and airspeed
• Maintain heading ±10°, altitude ±100 feet, and airspeed ±10 knots
• Apply adjustments to the published MDA and visibility as required
• Complete the final approach segment within ±10° heading
• Descend to the MDA and maintain within +100/-0 feet
• Execute the missed approach at the MAP if required visual references not acquired
• Use single-pilot resource management or crew resource management as appropriate

Partial panel approach technique:

Pre-approach preparation:

1. Brief approach thoroughly while in VMC or stable cruise: identify FAF, stepdowns, MAP timing/fixes, missed approach procedure
2. Write key altitudes, headings, times on kneeboard or approach plate
3. Set up navigation equipment: frequencies, courses, GPS waypoints
4. Verify standby instruments are functioning
5. Reduce airspeed to approach speed (typically 60-70 KIAS for most trainers) before IAF
6. Advise ATC of partial panel status

Approach segment breakdown:

Initial and intermediate segments:

• Maintain assigned altitudes ±100 feet using altimeter and VSI; cross-check with airspeed
• Intercept and track courses using CDI and heading (compass if heading indicator failed)
• Turn coordinator for all turns: standard rate (3° per second); calculate time for heading changes (60° turn = 20 seconds standard rate)
• Call out altitudes approaching stepdowns: “500 feet to 3,000, beginning descent”

Final approach segment (FAF to MAP):

• Configure helicopter: approach speed, heading, descent rate (typically 400-500 FPM for 3° glidepath approximation)
• On steam gauges: establish pitch using power setting and verify with altimeter, airspeed, VSI trends
• Use formula: Groundspeed ÷ 2 × 10 = descent rate for 3° path (Example: 60 knots GS = 300 FPM descent; this provides stable approach profile similar to ILS)
• Maintain descent rate without chasing; if altitude is 50 feet high at midpoint, adjust descent rate by 100 FPM rather than diving to correct
• Track final approach course within ±10° using CDI and heading source
• Level off at MDA smoothly — Lead level-off by 10% of descent rate (if descending 500 FPM, start leveling 50 feet prior to MDA)

MDA to MAP:

• Maintain MDA +100/-0 feet
• Continue to MAP using timing or GPS/DME distance
• Look for visual references (approach lights, runway environment)
• If visual references not acquired by MAP, execute immediate missed approach

Missed approach:

• Simultaneously: add power, establish climb attitude (use power setting, airspeed, altimeter, VSI)
• Track missed approach course using navigation equipment
• If vacuum failure (no attitude indicator or heading indicator): use turn coordinator for turns, compass for heading verification, altimeter and airspeed for pitch
• Comply with published altitudes and clearance limit
• Advise ATC: “Helicopter 123, missed approach, partial panel, request vectors”

Workload management during approach:

• Minimize radio work: Use brief transmissions (“123, roger” instead of full readbacks unless required)
• Delay non-essential tasks: Do not attempt to reprogram GPS, copy ATIS, or calculate fuel during final approach segment
• Verbalize key actions: “Approaching FAF, configure for descent,” “MDA, level off, start timing”
• Cross-check continuously: “Altitude good, heading left 2 degrees, correcting”

Single-Pilot Resource Management (IH.VIII.C.S3)

SRM definition: The art and science of managing all resources (both onboard and outside the aircraft) available to a single pilot to ensure the successful outcome of the flight.

Application during partial panel approach:

Automation management:

• If GPS is functioning, use for navigation situational awareness and distance to MAP/fixes
• Do not over-rely on automation; GPS can fail or lose signal; maintain scan on primary navigation source (VOR/LOC/CDI)
• Program GPS in advance; do not attempt reprogramming during high-workload phases

Risk assessment:

• PAVE checklist: Pilot (proficiency?), Aircraft (what failed and what works?), enVironment (weather at minimums?), External pressures (must land here or can divert?)
• CARE checklist: Consequences (what happens if I miss approach?), Alternatives (VMC nearby? Other airports?), Reality (am I capable of this approach partial panel?), External pressures (self-induced pressure to complete?)

Aeronautical decision-making: Use DECIDE model:

1. Detect — Recognize that primary instrument has failed
2. Estimate — What is the significance? Can I safely continue IFR?
3. Choose — Select course of action: continue to destination, divert to VMC, request surveillance approach
4. Identify — What actions are needed? Notify ATC, reduce workload, simplify approach
5. Do — Execute decision
6. Evaluate — Is the plan working? Am I maintaining control margins?

Controlled flight into terrain (CFIT) awareness:

• Partial panel approaches have higher CFIT risk due to workload and potential disorientation
• Verify altimeter setting is current
• Cross-check GPS altitude against barometric altitude
• Use all available terrain awareness: TAWs if installed, sectional chart terrain elevation review, ATC altitude confirmations
• Never descend below MDA without required visual references

Passenger management:

• Brief passengers before approach: “We have an instrument problem; I need complete silence during the next 10 minutes; I’ll let you know when we’re safely on the ground”
• If passenger becomes alarmed, short reassurance: “Everything is under control, I just need to concentrate” — then return full attention to flying

ATC as resource:

• Request altitude/heading confirmations: “Confirm you show me at 2,500 feet?”
• Request radar vectors to simplify navigation
• Request surveillance approaches (ASR) if available: controller provides all headings and altitude calls; pilot only maintains control
• If workload is unmanageable, inform ATC: “Need to reduce radio calls, will advise when stabilized”

Summary

Approach with loss of primary flight instruments is an emergency that tests every aspect of instrument flying skill, especially in helicopters where single-pilot workload is already high and no autopilot backup is available. Success depends on immediate recognition of the failure, disciplined transition to standby instruments, workload management, effective use of ATC resources, and adherence to stabilized approach principles. Pilots must practice partial panel proficiency regularly—the time to discover skill deficiencies is not in actual IMC with a failed instrument.

Schedule

Notes:

• Flight time may extend to 120 minutes if student requires additional approaches to achieve proficiency
• If weather permits, conduct actual IMC approach for realism, but ensure student has demonstrated partial panel proficiency under the hood first
• Consider splitting lesson into two flights if student shows significant difficulty with partial panel scan establishment

Equipment

Required References

• FAA-S-ACS-14 — Instrument Rating – Helicopter Airman Certification Standards (current edition)
• FAA-H-8083-15B — Instrument Flying Handbook (Chapters 5: Flight Instruments, 7: Helicopter Attitude Instrument Flying, 10: IFR Emergencies)
• FAA-H-8083-21B — Helicopter Flying Handbook (Chapter 11: Helicopter Emergencies)
• 14 CFR Parts 91 — General Operating and Flight Rules (§91.3, §91.185, §91.205, §91.213)
• Aeronautical Information Manual (AIM) — Chapter 5, Section 5-5-11 (Emergencies)
• Instrument Approach Procedures — Current approach plates for practice approaches (2 different non-precision approaches)
• ASA Instrument Pilot Oral Exam Guide — Emergency operations section

Training Aids and Materials

• View-limiting device (hood) — IFR training hood or Foggles
• Instrument covers or cards — To simulate failed instruments in steam gauge panel (post-it notes or purpose-made covers)
• Approach plate kneeboard — For student to use during flight
• Whiteboard or tablet — To diagram instrument scan patterns and failure recognition techniques
• Pilot’s Operating Handbook (POH) — For the training helicopter being used (R22, R44, Schweizer 300C, etc.)
• IFR navigation chart — Current low-altitude en route chart for area of operation
• Checklist — Aircraft-specific emergency checklist including partial panel procedures (if available)

Visual Aids

• Instrument panel diagrams — Glass cockpit PFD layout showing failure indications (red X symbols, warning messages)
• Steam gauge panel diagram — Showing six-pack layout and standby/backup instruments
• Partial panel scan pattern chart — Recommended instrument scan for attitude indicator failure and vacuum system failure
• Comparison chart — Primary instruments vs. standby instruments in various failure scenarios
• Turn coordinator diagram — Showing standard rate turn indication (one-bar-width deflection) and calculation methods (3° per second, 2 minutes for 360°)
• Magnetic compass error diagram — Illustrating ANDS (acceleration/deceleration errors) and UNOS (turning errors)

Aircraft and Equipment

• IFR-certified helicopter — Must meet 14 CFR §91.205(d) equipment requirements; suitable examples: Robinson R44 Raven II IFR, Schweizer 300CBi, Enstrom 280FX
• Functioning standby instruments — Verified operational before flight
• Operational navigation equipment — VOR/ILS receiver, GPS (if installed), operable CDI
• Functioning communication radios — VHF comm for ATC contact
• Current database — GPS databases must be current if using GPS for approaches
• Adequate fuel — Sufficient for lesson flight time plus 30-minute reserve (account for approaches requiring holds or missed approaches)

Airport and Airspace Requirements

• Class D or controlled airport with published instrument approaches — Preferably with tower and approach control
• Two different non-precision approaches available — VOR, RNAV (GPS), LOC approaches; avoid precision approaches for this lesson
• ATC coordination — Notify ATC in advance of training flight with multiple approaches and partial panel practice requests

Instructor Materials

• CFI lesson plan notebook — This lesson plan
• Grading sheet — ACS IH.VIII.C standards checklist for evaluating student performance
• Training record forms — For endorsement and record of training
• Scenario cards — Pre-written failure scenarios to introduce at various points during flight

Instructor Actions

1. Conduct preflight briefing covering lesson objectives, ACS standards IH.VIII.C, and scenario overview. Explain to student: “Today we’re training for one of the most serious IFR emergencies—losing your primary flight instruments in the clouds. In a helicopter without an autopilot, you’re the only thing keeping the aircraft under control. We’ll learn to recognize failures, transition to standby instruments, manage the workload, and complete a safe approach. Your completion standard is to fly a full non-precision approach partial panel while meeting the same tolerances as a normal approach: ±100 feet altitude, ±10° heading, ±10 knots airspeed.”

2. Review the regulatory requirements for IFR equipment per 14 CFR §91.205(d). Use the aircraft’s instrument panel to identify each required instrument. Explain: “If any of these instruments fail in flight, the aircraft may no longer be legal for IFR operations under Part 91, but as pilot-in-command under §91.3, you have emergency authority to deviate from regulations to safely handle the situation. Your job is to recognize the failure, maintain control, advise ATC, and get the helicopter on the ground safely—either continuing to destination if capable or diverting to VMC.”

3. Demonstrate recognition of instrument failures using the aircraft panel or training aids. For glass cockpit: Show examples of PFD failures (red X displays, AHRS failure warnings). For steam gauge: Explain how to cross-check instruments to detect failures. “If you’re in a turn and the attitude indicator shows wings level, it’s failed. If you’re in straight-and-level flight and the heading indicator is rapidly precessing, it’s suspect. Cross-checking is the only way to detect insidious failures before they cause disorientation.”

4. Explain failure modes and compensation techniques for each primary instrument. Walk through the aircraft panel: “Attitude indicator failure: transition immediately to turn coordinator for bank control, altimeter and airspeed for pitch. Heading indicator failure: use magnetic compass in straight flight, turn coordinator for turns. Vacuum failure: you lose both attitude and heading simultaneously—this is the toughest scenario.” Use diagrams to show partial panel scan patterns. “Your scan must be more deliberate and rapid because information is distributed across multiple instruments instead of the centralized attitude indicator.”

5. Discuss risk management factors per ACS IH.VIII.C.R1-R3. Emphasize helicopter-specific risks: “Helicopters are dynamically unstable. You can’t take your hands off the controls even for a second. There’s no autopilot in most trainers. Single-pilot IFR workload is already high, and losing instruments pushes you toward task saturation quickly. You must ruthlessly prioritize: fly the helicopter first, navigate second, communicate third. If you’re behind and getting disoriented, tell ATC ‘standby’ and focus on control.”

6. Teach ATC communication phraseology for advising reduced capability per ACS IH.VIII.C.S1. Provide examples and have student practice: “Approach, Helicopter 739 Delta Hotel, we’ve lost our primary attitude indicator, partial panel operations, request vectors for the approach and priority handling.” Emphasize: “Don’t be embarrassed or delay. ATC can help you—they can provide altitude/heading confirmations, vectors to minimize navigation workload, or surveillance approaches if available. The sooner you tell them, the sooner they can assist.”

7. Brief the partial panel approach technique thoroughly before flight. Use approach plates for the planned approaches. “We’ll fly a VOR approach partial panel. Before the IAF, you’ll be established in approach configuration—60 knots or your aircraft’s recommended approach speed. I’ll simulate the failure by covering the attitude indicator. Your scan immediately transitions to turn coordinator, altimeter, airspeed, VSI. You’ll intercept the final approach course, descend at 400-500 FPM to the MDA, level off, track to the MAP, and execute the missed approach. Verbalize your actions: ‘Approaching FAF, beginning descent, power to 20 inches, descent rate 500 FPM.’”

8. Conduct preflight inspection with emphasis on standby instrument verification. Check that standby attitude indicator (if electric) is powered, standby altimeter and airspeed are reading correctly, turn coordinator is functioning, magnetic compass is full and free. “Before every IFR flight, verify your backups work. In actual IMC, if your PFD fails and your standby instruments are also inoperative, you’re in an immediate emergency with very limited options.”

9. Demonstrate proper partial panel scan pattern during initial climb under the hood. After departure, establish student under the hood. Instructor covers attitude indicator or simulates PFD failure. Demonstrate: “Wings level: turn coordinator centered. Pitch for climb: airspeed decreasing to climb speed, altimeter and VSI showing positive rate, manifold pressure set for climb power. Heading: use heading indicator if functioning, or compass. Scan: turn coordinator, airspeed, altimeter, VSI, heading, back to turn coordinator. Smooth scan, no fixation.” Then: “Your controls, establish a 500 FPM climb to 3,000 feet, heading 360.”

10. Coach student through establishing straight-and-level flight partial panel. “Level off at 3,000. Lead by 50 feet. Power to cruise setting—22 inches. Airspeed should stabilize at 90 knots. Altimeter holding—good. Heading drifting right—turn coordinator shows right wing low—apply left cyclic to level wings. VSI showing 100 FPM climb—reduce collective slightly. Cross-check: altitude, airspeed, heading. If airspeed is decreasing and altitude is constant, you’re too slow—nose down or add power. If airspeed is increasing and altitude is constant, you’re too fast—nose up or reduce power.”

11. Demonstrate and coach standard rate turns partial panel. “We’ll turn right to heading 090. Standard rate turn: turn coordinator one bar width deflection. That’s 3 degrees per second. From 360 to 090 is a 90-degree turn, which takes 30 seconds at standard rate. Start the turn: smoothly apply right cyclic until turn coordinator shows standard rate deflection. Hold it there. Ball centered with pedals. Heading indicator turning—or count time and magnetic compass. 30 seconds: begin roll out. Lead by 5-10 degrees. As you roll out, verify wings level on turn coordinator, check heading.” Have student practice 90-degree and 180-degree turns to both left and right.

12. Demonstrate and coach partial panel climbs and descents. “Establish a 500 FPM climb. Add power to climb setting—24 inches. Airspeed will decrease slightly—that’s normal. Altimeter and VSI show climb—good. Turn coordinator: keep wings level. Now descend 500 FPM. Reduce power to 18 inches. Nose will lower—you’ll feel it, but verify with airspeed increasing slightly and VSI showing descent. Level off at 2,500 feet. Lead by 50 feet. Power back to level flight setting. Verify altitude holding with altimeter and zero on VSI.”

13. Set up for first partial panel approach. Coordinate with ATC: “Approach, Helicopter 739DH is a training flight, requesting the VOR Runway 18 approach, we’ll be simulating partial panel operations.” Vectors to IAF. Before IAF: “Configure for approach: slow to 60 knots, power approximately 20 inches, trim. Verify standby instruments. I’m simulating attitude indicator failure—now.” Cover attitude indicator with approach plate. “Your scan is now turn coordinator, airspeed, altimeter, VSI, heading. Maintain altitude and heading to the IAF.”

14. Coach student through approach segments providing progressive assistance as needed. Initial segment: “Intercept the 180 radial inbound. Turn to 180—that’s a 90-degree right turn from present heading. Use standard rate. Good. CDI is centering—you’re on course. Altitude 3,000—maintain until FAF.” Final segment: “Approaching FAF. Configure for descent: maintain 180 heading, power to 18 inches, establish 500 FPM descent. Altimeter descending—good. Airspeed 60 knots—good. Track the radial—slight right drift, correct 5 degrees right. Approaching MDA—2,000 feet. Lead your level-off by 50 feet. Power to level—20 inches. Altitude holding at 2,000—good.”

15. Monitor for deviations exceeding ACS standards and provide corrective guidance. If student altitude deviates beyond ±100 feet: “Altitude—you’re 150 feet high. Reduce power slightly, establish 200 FPM descent back to MDA.” If heading deviates beyond ±10°: “Heading—you’ve drifted 15 degrees left. Turn coordinator shows left wing low. Level the wings, then turn right 15 degrees to re-intercept course.”

16. Call the MAP and instruct student to execute missed approach partial panel. “MAP—now. Execute the missed approach. Simultaneously: power to climb—24 inches. Pitch for climb—airspeed should hold or decrease slightly to climb speed. Altimeter and VSI show positive rate—good. Turn to missed approach heading—270 degrees. That’s a right turn—calculate turn time or use turn coordinator. Climb to 3,000 feet. Advise ATC: ‘Approach, 739 Delta Hotel, missed approach.’”

17. Debrief first approach and set up for second approach. “Good work. Your scan was solid. I noticed you chased altitude slightly on final—remember, if you’re 50 feet high halfway down, adjust descent rate by 100 FPM rather than diving to correct immediately. Let’s try another approach—this time an RNAV approach. We’ll shoot the RNAV 36 approach. Same procedures: I’ll simulate the failure, you’ll fly the approach partial panel.” Coordinate with ATC for the second approach.

18. Conduct second partial panel approach with reduced coaching to assess independent proficiency. Allow student to manage approach more independently. Provide coaching only if deviations approach unsafe limits or exceed ACS standards significantly. Observe decision-making, SRM application, workload management, communication effectiveness.

19. If time and fuel permit, introduce additional failure scenario such as heading indicator failure during approach. “On this approach, I’m simulating vacuum system failure—you’re losing both attitude indicator and heading indicator. Use turn coordinator for all bank control, magnetic compass for heading in straight flight, calculated turns using time and turn coordinator for heading changes.” This increases realism and difficulty. Monitor student closely for signs of task saturation or disorientation.

20. Terminate approaches when completion standards are met or at instructor discretion if student requires additional training. If student consistently meets ACS standards IH.VIII.C by second approach: “Excellent. You’ve demonstrated the ability to recognize the failure, maintain control, and complete a safe approach. Remove the hood, we’ll return and land.” If student requires more practice: “We’ll schedule another flight to continue practicing partial panel approaches. Today you’ve made solid progress on scan and control, but we need to refine altitude control on final. Review the partial panel scan pattern before next flight.”

21. Conduct post-flight debrief covering performance against ACS standards IH.VIII.C. Use grading sheet. Review each approach: “First approach: you maintained altitude within standards until final segment where you went 120 feet high—just outside tolerance. Heading control was good, within 10 degrees throughout. Second approach: altitude within 50 feet, heading within 5 degrees, airspeed within 5 knots—well within standards. Your communication was clear and you appropriately requested vectors. You demonstrated good SRM by verbalizing your actions and staying ahead of the aircraft.”

22. Discuss risk management and decision-making. Ask: “If this had been actual IMC and the failure was real, what would you have considered in deciding whether to continue the approach or divert?” Expected student response should include weather at minimums, personal proficiency, fuel, availability of simpler approach, ATC assistance availability. Reinforce correct risk assessment.

23. Address areas for improvement and assign self-study. “For next flight, review the magnetic compass errors—ANDS and UNOS—because if you lose your heading indicator, you’ll rely on the compass. Also review the VOR and RNAV approach procedures to reduce navigation workload. The better you know the approach before you shoot it, the more brain capacity you have for aircraft control. Practice partial panel chair flying at home: visualize the scan pattern, verbalize control inputs.”

24. Complete training records and provide endorsement if student meets standards. If proficiency is demonstrated: Make logbook entry: “Dual instruction given: Instrument helicopter emergency operations—approach with loss of primary flight instrument indicators per ACS IH.VIII.C. Student demonstrated ability to recognize instrument failures, transition to partial panel, communicate with ATC, and complete non-precision approaches within ACS standards.” If additional training is needed: “Dual instruction given: Instrument helicopter emergency operations—partial panel approach introduction. Student requires additional practice to meet ACS completion standards. Proficiency to be demonstrated on follow-up flight.”

25. Brief student on continued practice and proficiency maintenance. “Partial panel proficiency degrades quickly. The FAA requires instrument currency but doesn’t specifically require partial panel practice. As a professional pilot, you should practice partial panel approaches periodically—at least every 6 months. During your instrument proficiency check, ask the examiner or instructor to include a partial panel approach. This isn’t just about passing a checkride—this is a survival skill. If your instruments fail in actual IMC and you can’t control the helicopter, the outcome is likely fatal. Take this training seriously.”

Student Actions

1. Participate actively in preflight briefing, taking notes on ACS standards IH.VIII.C and completion criteria. Ask clarifying questions about objectives and expectations for the lesson.

2. Review aircraft instrument panel during ground instruction, identifying each required IFR instrument per 14 CFR §91.205(d). Point out primary flight instruments (attitude indicator, heading indicator, altimeter, airspeed indicator, VSI, turn coordinator) and standby instruments in the specific training aircraft being used.

3. Study failure recognition techniques for both glass cockpit and steam gauge configurations. Practice identifying instrument failures using panel diagrams or training aids: “If I see a red X on the PFD attitude display, that indicates AHRS failure. If the attitude indicator shows wings level but the turn coordinator shows a turn, the attitude indicator has failed.”

4. Demonstrate understanding of compensation techniques by explaining partial panel scan pattern. Student should be able to describe: “If I lose the attitude indicator, my scan becomes turn coordinator for bank control, altimeter and airspeed for pitch control. For heading, I use the heading indicator if it’s working, or magnetic compass if vacuum system failed. My scan is: turn coordinator, airspeed, altimeter, VSI, heading source, back to turn coordinator—continuous, deliberate scan with no fixation.”

5. Practice ATC communication phraseology for advising partial panel operations. Student rehearses example calls: “Approach, Helicopter 123 Alpha Bravo, partial panel due to attitude indicator failure, request vectors for the approach and priority handling.” Instructor critiques and corrects phraseology until student demonstrates clear, concise communication.

6. Complete preflight inspection with emphasis on verifying standby instrument operation. Student checks: standby attitude indicator power and operation, standby altimeter reading correctly, standby airspeed indicator reading correctly, turn coordinator functioning, magnetic compass full and free. Report findings to instructor.

7. Establish aircraft control under the hood using full panel, then transition to partial panel when instructor simulates failure. After takeoff and initial climb, student flies under the hood. When instructor covers attitude indicator or announces “PFD failure,” student immediately transitions scan to partial panel instruments and maintains heading, altitude, and airspeed within tolerances.

8. Practice straight-and-level flight partial panel, maintaining altitude ±100 feet, heading ±10°, airspeed ±10 knots. Student demonstrates disciplined scan pattern. Verbalizes cross-checks: “Altitude 3,000 holding, airspeed 90 knots, turn coordinator level, heading 360 steady.” Makes small corrections when deviations are detected: “Altitude trending down 50 feet, slight collective increase.”

9. Perform standard-rate turns partial panel to assigned headings. Student demonstrates proper technique: “Turning left to 270. Standard rate—turn coordinator one bar width. Holding standard rate. 90-degree turn takes 30 seconds. Beginning roll-out at 275. Wings level, heading 270.” Maintains altitude within ±100 feet throughout turns.

10. Execute climbs and descents partial panel to assigned altitudes at 500 FPM rate. Student demonstrates: “Climbing to 4,000 feet, 500 FPM. Power to 24 inches. Airspeed 70 knots. VSI shows 500 FPM—good. Altimeter passing 3,500. Turn coordinator level—on heading. Approaching 4,000—lead by 50 feet. Power reduction to level flight. Altitude 4,000, holding.”

11. Receive vectors to IAF and configure aircraft for approach before simulated instrument failure. Student slows helicopter to approach speed (typically 60 KIAS for trainers), sets appropriate power setting, uses force trim if available, completes approach checklist. Reports: “Configured for approach: 60 knots, 20 inches manifold pressure, trimmed.”

12. Transition to partial panel scan when instructor simulates attitude indicator or PFD failure. Student acknowledges: “Attitude indicator failed, transitioning to partial panel, turn coordinator for bank, altimeter and airspeed for pitch.” Maintains altitude and heading while transitioning scan. Does not fixate on failed instrument.

13. Navigate to and identify the IAF using available navigation equipment. Student uses VOR or GPS navigation, identifies IAF passage, reports to ATC: “Approach, 123 Alpha Bravo, at JAMID inbound.” Maintains altitude assigned until cleared for approach.

14. Intercept final approach course and track within ±10° heading tolerance. Student uses CDI for course guidance, heading source (heading indicator or compass) for heading control, turn coordinator for bank control. “Intercepting final approach course, turning inbound to 180. CDI centering. On course, 180 heading.”

15. Descend from FAF at stabilized descent rate (400-500 FPM) while maintaining airspeed ±10 knots and tracking course. Student configures for descent: reduces power, verifies descent rate on VSI, monitors airspeed, maintains heading. Verbalizes: “FAF passage, beginning descent. Power to 18 inches. Descent rate 500 FPM. Airspeed 60 knots. On course heading 180.”

16. Level off at MDA +100/-0 feet and maintain while proceeding to MAP. Student leads level-off by 50 feet, smoothly increases power to level flight setting, verifies altitude holding with altimeter and VSI. “Approaching MDA 2,000 feet. Leveling. Altitude 2,000 holding. VSI zero. Proceeding to MAP.”

17. Monitor for required visual references and call out MAP timing or distance. Student monitors clock or GPS distance to MAP. Looks outside for visual references if simulating VMC break-out. Calls: “One mile to MAP. 30 seconds to MAP. No visual references—will execute missed approach.”

18. Execute missed approach at MAP per published procedure. Student simultaneously adds power to climb setting, establishes climb attitude using partial panel scan (altimeter and airspeed for pitch, turn coordinator for bank), turns to missed approach heading, climbs to assigned altitude. Advises ATC: “Approach, 123 Alpha Bravo, missed approach, climbing runway heading.”

19. Maintain aircraft control throughout missed approach while complying with published procedure and ATC clearance. Student navigates missed approach route, maintains heading and altitude assignments, communicates with ATC for further clearance or vectors to second approach.

20. Request ATC assistance as needed using proper phraseology per IH.VIII.C.S1. If workload becomes high or clarification is needed: “Approach, 123 Alpha Bravo, request you confirm my altitude, partial panel.” Or: “Request extended final for configuration and workload management.”

21. Conduct second partial panel approach with increased independence. Student demonstrates improved proficiency, smoother scan, better altitude and heading control, anticipating approach segments. Requires less coaching from instructor. Demonstrates SRM by verbalizing actions: “Approaching FAF, configuring for descent, briefing missed approach procedure.”

22. Demonstrate single-pilot resource management (SRM) throughout approaches per IH.VIII.C.S3. Student prioritizes tasks appropriately: aircraft control first, then navigation, then communication. Uses all available resources: GPS for distance information, ATC for altitude/heading confirmation. Verbalizes situational awareness: “Five miles from FAF, altitude 3,000 feet, on course, configured for approach.”

23. Recognize and advise instructor of task saturation or disorientation if it occurs. Student should state: “I’m getting behind, need to focus on control” or “I’m uncertain of aircraft position, requesting vectors.” Demonstrates self-awareness and good decision-making rather than attempting to continue when unsafe.

24. Participate in post-flight debrief, self-assessing performance against ACS standards. Student reviews each approach: “On the first approach I went 120 feet high on final and had to make a large correction. I was chasing the altitude instead of setting a descent rate and letting it stabilize. On the second approach I did better—set 500 FPM, monitored it, made small corrections. I stayed within 50 feet the whole final segment.”

25. Discuss decision-making and risk assessment for partial panel operations. Student explains what factors would influence decision to continue or divert: “If the weather was at minimums and I wasn’t confident in my partial panel skills, I’d divert to VMC. If I had good weather, ATC support, and felt in control, I’d continue. Fuel and approach complexity also matter—if it’s a complicated approach with procedure turn, I’d request vectors or a simpler approach.”

26. Identify areas for personal improvement and commit to self-study assignments. Student acknowledges: “I need to practice magnetic compass use more—I wasn’t confident in the turning errors. I’ll review ANDS and UNOS and practice compass turns on the next flight. I also need to study the approach plates more thoroughly so I can reduce navigation workload during partial panel.”

27. Schedule follow-up training if needed or demonstrate readiness for IFR partial panel operations. If proficiency is not yet at standard: “I’d like to schedule another flight to practice partial panel approaches before my instrument checkride.” If proficiency is demonstrated: “I feel confident I could handle a real partial panel situation. I know to maintain control first, advise ATC, use all resources, and complete a safe approach or divert to VMC if necessary.”

Completion Standards

The lesson is complete when the student demonstrates competency in recognizing primary flight instrument failures, transitioning to partial panel operations, maintaining aircraft control under increased workload, and safely conducting instrument approaches using standby instruments, meeting all knowledge, risk management, and skill elements of ACS IH.VIII.C — Approach with Loss of Primary Flight Instrument Indicators.

Knowledge Requirements (IH.VIII.C.K1, IH.VIII.C.K2)

The student must demonstrate understanding of:

• IH.VIII.C.K1: Ability to recognize if primary flight instruments are inaccurate or inoperative within 10 seconds of occurrence through cross-checking techniques, and properly advise ATC or evaluator using standard phraseology (e.g., “Approach, Helicopter N123AB, partial panel operations due to attitude indicator failure, request vectors and priority handling”).

• IH.VIII.C.K2: Thorough knowledge of possible failure modes including:

  • Glass cockpit: PFD failure (complete loss, partial display loss with red X indications, AHRS failure affecting attitude/heading, ADC failure affecting altitude/airspeed/VSI)
  • Steam gauge: individual instrument failures (attitude indicator precession or tumbling, heading indicator precession, altimeter freezing, airspeed indicator blockage, VSI lag or freezing, turn coordinator failure) and system failures (vacuum system failure causing simultaneous loss of attitude and heading indicators)
  • Proper compensation techniques for each failure type using remaining functional instruments
  • Cross-checking methods to detect failures: comparing attitude indicator movement with turn coordinator, comparing heading indicator with magnetic compass, verifying altimeter against VSI and airspeed trends

Risk Management Requirements (IH.VIII.C.R1, IH.VIII.C.R2, IH.VIII.C.R3)

The student must demonstrate:

• IH.VIII.C.R1 — Use of secondary flight displays when primary displays have failed:

  • Immediate transition to standby instruments or remaining functional instruments without delay or confusion
  • Proper scan pattern for partial panel operations (turn coordinator, altimeter, airspeed, VSI, heading source in appropriate sequence)
  • Verification that standby/backup instruments are functioning accurately before relying on them
  • Awareness of standby instrument limitations (e.g., magnetic compass errors, turn coordinator providing only bank/turn information without pitch reference)

• IH.VIII.C.R2 — Maintaining helicopter control:

  • Prioritization of aircraft control above all other tasks (Aviate, Navigate, Communicate hierarchy)
  • Recognition that helicopters require continuous control inputs and lack autopilot backup in most training aircraft
  • Appropriate use of trim systems (force trim in R44 IFR) to reduce control pressures
  • Limiting maneuvering to standard-rate turns maximum and stabilized descent rates (400-500 FPM)
  • Maintaining approach speed or higher to preserve adequate control margins
  • Avoiding configuration changes unless necessary to reduce workload during control transition

• IH.VIII.C.R3 — Distractions, task prioritization, loss of situational awareness, or disorientation:

  • Immediate covering or ignoring of failed instrument(s) to prevent distraction by false information
  • Effective task prioritization using single-pilot resource management: control first, navigation second, communication third
  • Recognition of personal limitations and task saturation; willingness to request ATC assistance or declare emergency when workload exceeds capability
  • Recognition of spatial disorientation symptoms and discipline to trust instruments completely
  • Appropriate use of verbalization to maintain situational awareness (“Approaching FAF, configuring for descent”)
  • Simplification of flight plan when necessary (requesting vectors, extended final, simpler approach type)

Skill Requirements (IH.VIII.C.S1, IH.VIII.C.S2, IH.VIII.C.S3)

The student must demonstrate:

• IH.VIII.C.S1 — Advise ATC or evaluator if unable to comply with clearance:

  • Prompt communication to ATC when primary instrument failure occurs, using phraseology such as “partial panel operations,” “reduced capability,” or “priority handling requested”
  • Clear statement of inability to comply with complex clearances (holding patterns, procedure turns, complex arrivals) when workload exceeds safe limits
  • Appropriate requests for assistance (vectors to final, altitude confirmations, surveillance approach) without hesitation or embarrassment
  • Use of standard emergency or urgency phraseology if situation warrants

• IH.VIII.C.S2 — Complete a non-precision instrument approach without use of primary flight instruments using skill elements of non-precision approach task (ACS IH.VI.A):

  Pre-approach:

  • Properly configure aircraft for approach (approach airspeed, power setting, trim)
  • Complete appropriate checklists
  • Brief approach thoroughly including altitudes, courses, timing, missed approach procedure

  Navigation:

  • Comply with all published minimum safe/sector altitudes
  • Properly identify and confirm operational status of navigation equipment (VOR, GPS)
  • Track courses within ±10° during initial, intermediate, and final segments using partial panel
  • Accurately identify FAF, step-down fixes, and MAP

  Aircraft Control (Primary Completion Standards):

  • Maintain altitude within ±100 feet during level segments using partial panel scan
  • Maintain heading within ±10° using turn coordinator, heading source, and course guidance
  • Maintain airspeed within ±10 knots of target approach speed
  • Establish and maintain stabilized descent rate (400-500 FPM) on final approach segment
  • Descend to MDA and maintain +100/-0 feet until MAP
  • Track final approach course within ±10° using available navigation guidance

  Approach completion:

  • Level off at MDA smoothly without descending below
  • Proceed to MAP while maintaining MDA and tracking final approach course
  • Execute timely missed approach at MAP if required visual references not acquired
  • During missed approach: simultaneously add power, establish climb, turn to missed approach heading, climb to assigned altitude—all using partial panel

  Communication:

  • Establish and maintain two-way communication with ATC
  • Comply with all ATC clearances and instructions unless unable (then advise ATC)
  • Provide position reports as required
  • Advise ATC of missed approach execution

• IH.VIII.C.S3 — Use single-pilot resource management (SRM) or crew resource management (CRM):

  • Demonstrate effective workload management by prioritizing tasks appropriately
  • Use all available resources: GPS for distance/situational awareness, ATC for altitude/heading confirmations, approach plate for procedure reminder
  • Maintain situational awareness through verbalization: “Five miles from FAF, 3,000 feet, on course”
  • Make sound aeronautical decisions regarding continuation vs. diversion based on weather, personal proficiency, fuel, approach complexity
  • Apply DECIDE model or equivalent decision-making framework
  • Demonstrate appropriate risk assessment using PAVE, CARE, or similar methodology
  • Manage distractions by maintaining control focus and delaying non-essential tasks
  • Request assistance from ATC when workload becomes high without allowing control to degrade

Overall Performance Standards

The student meets completion standards when:

1. Knowledge elements are demonstrated through verbal explanation of failure modes, compensation techniques, and recognition methods during ground and flight portions.

2. Risk management is consistently applied throughout partial panel operations: proper use of standby instruments, maintenance of helicopter control as first priority, and effective management of distractions and workload.

3. Skills are demonstrated to ACS standards by completing at least one (preferably two) non-precision instrument approaches partial panel with:

   • Altitude maintained within ±100 feet during all segments
   • Heading maintained within ±10° during all segments
   • Airspeed maintained within ±10 knots during all segments
   • MDA maintained +100/-0 feet from FAF to MAP
   • Timely and proper missed approach execution
   • Effective communication with ATC including advising of partial panel status and requesting assistance as appropriate
   • Sound aeronautical decision-making and single-pilot resource management throughout

4. The student demonstrates competency and confidence in handling primary instrument failures in IMC, recognizing that while partial panel operations are more challenging and higher workload, they can be managed safely through disciplined scan technique, effective risk management, and appropriate use of all available resources.

Instructor Assessment: The CFI will evaluate performance against this completion standard using the ACS IH.VIII.C criteria and determine whether the student is proficient in approach with loss of primary