Cessna 172N IFR Equipment & Systems — Instrument Rating Oral Questions

DPE oral questions · ifr equipment & systems

29 questions a DPE may ask in this section

1. Question 1 · IR.I.F.K1

   You are in solid IMC at 8,000 feet. Your primary flight display (or attitude indicator) suddenly fails. Walk me through your immediate actions and what you would use for attitude reference.

   What a DPE expects to hear

   • Declare the emergency/abnormality and advise ATC if appropriate
   • Immediately cross-check remaining instruments for attitude reference
   • Maintain control — attitude reference is critical in IMC
   • Report the failure to ATC and request vectors if needed
   • Refer to aircraft-specific backup instruments and procedures

   Common wrong answers

   • Trying to reset/recycle a failed AI while still flying — aviate first
   • Not knowing what backup attitude reference is available
   • Panic-induced loss of aircraft control

   SourceFAA-H-8083-16B Chapter 7; FAA-H-8083-15B; PilotsCafe IFR Quick-Review p.11

2. Question 2 · IR.I.F.K1

   Your vacuum pump fails in IMC. What instruments are affected, and what do you have remaining for attitude reference?

   What a DPE expects to hear

   • Vacuum-powered instruments (typically): Attitude Indicator (AI) and Directional Gyro (DG/HSI with vacuum gyro)
   • NOT vacuum-powered (typically electric): Turn Coordinator, Altimeter, Airspeed Indicator, VSI
   • Immediate action: recognize the failure (suction gauge at zero), cover the AI and DG to avoid being misled by their slowly erring indications
   • Remaining usable instruments: TC (for bank), altimeter (pitch), ASI (pitch/airspeed), VSI (pitch trend), magnetic compass (heading)
   • Fly partial-panel technique — TC-based scan

   Common wrong answers

   • Continuing to trust a slowly erring vacuum AI (very dangerous)
   • Not knowing the TC is electric and still usable
   • Forgetting to cover the failed instruments to avoid fixation

   SourceFAA-H-8083-16B Chapter 7; FAA-H-8083-15B; PilotsCafe IFR Quick-Review p.11, 12

3. Question 3 · IR.I.F.K1

   What are the effects on the pitot-static instruments when the static port becomes blocked (clogged)?

   What a DPE expects to hear

   • Altimeter: freezes at the altitude where the port blocked; no longer changes with actual altitude
   • VSI: immediately shows zero and stays at zero (no static pressure differential)
   • Airspeed Indicator: becomes unreliable — may over-read during descent (trapped static pressure is higher than outside), under-read during climb; may read correctly in level flight at the same altitude
   • Remedy: alternate static source (slightly higher pressure than outside — small corrections required); or break the VSI glass as a last resort to use cabin air pressure

   Common wrong answers

   • Thinking the ASI goes to zero when static port blocks (wrong — it becomes unreliable, not zero)
   • Not knowing VSI shows zero immediately
   • Not knowing altimeter freezes at blockage altitude

   SourceFAA-H-8083-16B Chapter 7; PilotsCafe IFR Quick-Review p.11

4. Question 4 · IR.I.F.K1

   What are the effects of a blocked pitot tube (with static port open)?

   What a DPE expects to hear

   • Airspeed Indicator: if static port is open but pitot tube is blocked, ASI reads zero in level flight (no ram air differential)
   • If pitot tube is blocked AND pitot drain hole is also blocked: ASI may over-read during climb (water sealed in tube expands with altitude change like an altimeter) or behave erratically
   • Altimeter: NOT affected — uses static only
   • VSI: NOT affected — uses static only
   • Pitot heat: prevents ice blockage of pitot tube; does NOT heat the static port

   Common wrong answers

   • Confusing pitot blockage with static blockage effects
   • Thinking pitot heat also heats the static port (it does not)
   • Not knowing the dual-blocked pitot/drain scenario — ASI acts like an altimeter

   SourceFAA-H-8083-16B Chapter 7; PilotsCafe IFR Quick-Review p.11

5. Question 5 · IR.I.F.K1

   What are the magnetic compass errors (DV MONA)?

   What a DPE expects to hear

   • D — Deviation: compass card deflected by aircraft magnetic fields; corrected by compass correction card in cockpit
   • V — Variation: difference between magnetic and true north; corrected by adding/subtracting variation (East is least, West is best)
   • M — Magnetic dip (Oscillation): compass bobs and weaves due to dip at low latitudes
   • O — Oscillation: erratic swings due to turbulence or uncoordinated flight
   • N — Northerly Turning Error (UNOS): In Northern hemisphere, compass leads during a turn from North, lags from South — UNOS: Undershoot North, Overshoot South
   • A — Acceleration Error (ANDS): acceleration = North indication; deceleration = South indication — ANDS: Accelerate North, Decelerate South
   • Most reliable: wings-level, constant speed, coordinated flight on an E/W heading

   Common wrong answers

   • Confusing ANDS and UNOS
   • Not knowing compass is most reliable on E/W headings
   • Forgetting deviation is a correctable, charted error

   SourceFAA-H-8083-16B Chapter 7; PilotsCafe IFR Quick-Review p.12

6. Question 6 · IR.I.F.K1

   Your alternator fails in IMC while cruising at 9,000 feet. The electrical load light comes on. Walk me through your immediate response and your options.

   What a DPE expects to hear

   • Confirm alternator failure: ammeter shows discharge or zero output; ALT light illuminated; bus voltage dropping
   • Turn off unnecessary electrical loads immediately to extend battery life: nav lights, ELT, non-essential avionics
   • Keep: COM radio (one), transponder (squawk 7600 or 7700 if emergency), essential nav instrument
   • Advise ATC of electrical failure — declare emergency if needed (§91.3)
   • Estimate battery life remaining (typical light aircraft battery: 20-30 minutes under normal loads; less if load not reduced)
   • Divert to nearest suitable airport immediately
   • On the ground: do not attempt to restart the alternator without understanding the cause

   Common wrong answers

   • Continuing to destination without shedding electrical load
   • Not advising ATC
   • Not knowing battery life limitation in this scenario
   • Forgetting to keep the transponder on as long as possible

   SourceFAA-H-8083-16B Chapter 7; 14 CFR §91.3; PilotsCafe IFR Quick-Review p.12

7. Question 7 · IR.I.F.K1

   What is RAIM and how does it affect your GPS approach?

   What a DPE expects to hear

   • RAIM = Receiver Autonomous Integrity Monitoring; the GPS receiver's self-checking system to verify satellite geometry is adequate for navigation
   • For enroute GPS: requires 5 satellites for RAIM; for approach: requires 6 satellites (or 5 + barometric altimeter input)
   • If RAIM is not available, the GPS cannot be used as a primary navigation source for IFR
   • Check RAIM availability before flight for approaches (www.faa.gov/air_traffic/flight_info/aeronav/acrobat/RAIM_prediction.pdf or apps/avionics)
   • WAAS-equipped aircraft: WAAS replaces RAIM with a more robust integrity system — FDE (Fault Detection and Exclusion)
   • Non-WAAS GPS: MUST predict RAIM availability for approach phase, especially at remote airports

   Common wrong answers

   • Thinking WAAS GPS still requires traditional RAIM prediction (WAAS uses FDE instead)
   • Not knowing the 6-satellite requirement for approach phase
   • Confusing RAIM with GPS database currency

   SourceAIM 1-1-17; PilotsCafe IFR Quick-Review p.8

8. Question 8 · IR.I.F.K1

   What is the difference between WAAS and non-WAAS GPS? What approach minimums does each support?

   What a DPE expects to hear

   • Non-WAAS (TSO-C129): provides lateral navigation; supports LNAV approaches with MDA; accuracy ~100 meters
   • WAAS (TSO-C145/146): Wide Area Augmentation System; provides both lateral AND vertical guidance; supports LPV, LNAV/VNAV, LNAV approaches; accuracy <3 meters
   • WAAS uses ground reference stations and a geostationary satellite to correct GPS errors in real time
   • LPV approaches (only with WAAS): glidepath guidance with precision-approach-like minimums (as low as 200 ft DA / 2400 RVR)
   • LNAV/VNAV: available with WAAS OR baro-VNAV; vertical guidance to MDA on the glidepath
   • Under ACS-8C: LPV satisfies the precision approach requirement

   Common wrong answers

   • Thinking non-WAAS GPS can fly LPV approaches
   • Not knowing WAAS replaces RAIM prediction need
   • Confusing LNAV/VNAV (available without WAAS with baro input) with LPV (WAAS only)

   SourceAIM 1-1-18; FAA-S-ACS-8C; PilotsCafe IFR Quick-Review p.8, 16

9. Question 9 · IR.I.F.K1

   What are the spatial disorientation illusions most likely to affect IFR pilots? Name at least five.

   What a DPE expects to hear

   • The Leans: only the vestibular system (semicircular canals), not visual — sudden level after prolonged bank causes sensation of banking opposite way; pilot leans to feel 'level'
   • Graveyard Spiral: sustained turn → semicircular canal fluid stops → feels level; correction returns roll sensation; pilot pushes forward to stop 'climb'
   • Somatogravic Illusion: rapid acceleration feels like nose-up pitch; pilot pushes forward into ground
   • Somatogyral Illusion: prolonged roll → fluid stops → feel upright; reversal feels like rotation opposite direction
   • Inversion Illusion: abrupt level-off from climb feels like tumbling backward
   • Elevator Illusion: updraft causes impression of climbing; pilot pushes forward
   • The Leans is the most common spatial disorientation in IFR

   Common wrong answers

   • Confusing the Leans with the Graveyard Spiral
   • Not knowing the Somatogravic illusion affects acceleration on takeoff (pushes forward into ground)
   • Thinking VFR visibility alone prevents spatial disorientation

   SourceFAA-H-8083-25C Chapter 17; PilotsCafe IFR Quick-Review p.25–27

10. Question 10 · IR.I.F.K1

    What is hypoxia and how does it affect an IFR pilot at altitude?

    What a DPE expects to hear

    • Hypoxia = insufficient oxygen supply to the brain; impairs judgment, reasoning, memory, and motor control
    • Insidious because the pilot typically feels fine and may feel euphoric — no pain, minimal warning
    • Onset: at 10,000 feet, night vision impaired; at 14,000 feet, performance significantly impaired; at 18,000 feet, incapacitation in ~30 minutes
    • IFR ops: §91.211 requires supplemental oxygen above 12,500 feet MSL for flights >30 minutes; above 14,000 feet at all times; above 15,000 feet for passengers at all times
    • Treatment: descend and use supplemental oxygen immediately upon recognition

    Common wrong answers

    • Thinking hypoxia causes obvious symptoms (it typically does not)
    • Confusing the altitude thresholds for oxygen requirements
    • Not knowing night vision is first to be impaired at altitude

    Source14 CFR §91.211; PHAK Chapter 17; PilotsCafe IFR Quick-Review p.25

11. Question 11 · IR.I.F.K1

    What are the kinds of operations for which your training aircraft is approved for IFR flight?

    What a DPE expects to hear

    • Each aircraft's POH Section 2 (Limitations) contains the 'kinds of operations' table
    • Typical light aircraft are approved for: Day IFR and Night IFR, with specific equipment requirements listed
    • Day IFR may require a different equipment list than Night IFR (e.g., navigation lights required for night; full panel including AI/DG for IFR)
    • Some aircraft are NOT certified for flight into known icing (most GA singles) — this appears in limitations
    • FIKI-certified aircraft: have specific anti-ice/de-ice equipment and limitations for flight into known icing

    Common wrong answers

    • Not knowing where to find kinds of operations in the POH
    • Thinking all aircraft are equally IFR certified
    • Not knowing icing certification appears in the limitations section

    Source14 CFR §91.9; POH Section 2; PilotsCafe IFR Quick-Review p.5

12. Question 12 · IR.I.F.K1

    On your pre-takeoff check, you find the pitot heat is inoperative. The forecast route is in clouds with temperatures between -2°C and +5°C — prime icing range. How does this affect your flight?

    What a DPE expects to hear

    • Pitot heat is NOT listed in §91.205(d) (GRAB CARD). Pitot-heat operability for IFR in icing is governed by the AFM/POH operating limitations (enforced via §91.9) and §91.213 (inoperative equipment). If the POH lists pitot heat as required for IFR, its failure renders the aircraft not airworthy under §91.213.
    • Without pitot heat, airspeed indicator is susceptible to icing in visible moisture at near-freezing temps
    • This is a go/no-go decision: if the flight will be in icing conditions (visible moisture + temp at or below 0°C), flying without functional pitot heat is unsafe
    • Per §91.213: if pitot heat is a required item on the MEL or required by §91.205, it cannot be deferred for IFR in icing conditions
    • Correct action: do not depart IFR in forecast icing without functional pitot heat

    Common wrong answers

    • Thinking pitot heat is optional because the aircraft has a working ASI
    • Not knowing pitot heat is specifically required for IFR under §91.205
    • Thinking 'minimum fuel, max range' solves the problem

    Source14 CFR §91.205(d); §91.213; PilotsCafe IFR Quick-Review p.12

13. Question 13 · IR.I.F.K1

    Your GPS receiver on the approach indicates 'RAIM not available' as you reach the FAF. What do you do?

    What a DPE expects to hear

    • If RAIM is not available at the FAF: you CANNOT fly the GPS/RNAV approach using GPS as the primary navigation source
    • Execute missed approach immediately
    • Advise ATC of GPS RAIM failure
    • Options: request an alternate approach procedure (ILS, VOR, LOC if available), divert to alternate, hold until RAIM is predicted to be available
    • WAAS aircraft: WAAS uses FDE (Fault Detection and Exclusion) not RAIM — a WAAS 'not available' flag may indicate different issue; check display annunciation
    • Non-WAAS GPS: RAIM failure = mandatory missed approach at FAF

    Common wrong answers

    • Continuing the approach anyway (illegal and unsafe)
    • Thinking you can use the GPS for advisory guidance only on an instrument approach (not allowed for primary IFR navigation without integrity monitoring)
    • Confusing WAAS FDE with traditional RAIM

    SourceAIM 1-1-17; PilotsCafe IFR Quick-Review p.8

14. Question 14 · IR.I.F.K1

    Explain the difference between the three levels of GPS sensitivity during an RNAV approach. When does each occur and why does it matter?

    What a DPE expects to hear

    • Enroute sensitivity: ±5.0 NM full-scale deflection; used during cruise flight
    • Terminal sensitivity: ±1.0 NM; activates within 30 NM of destination or when selected terminal mode
    • Approach sensitivity: ±0.3 NM (LNAV); activates 2 NM before FAF when approach mode is armed
    • LPV approach: additional angular sensitivity (like an ILS) activates on final — narrows from 0.3 NM to ±350 feet at threshold
    • Why it matters: if sensitivity doesn't switch to approach mode, you're flying with 1.0 NM CDI deflection on final — huge error. Must verify 'LNAV' or 'LPV' is annunciated before FAF.
    • Practical: if GPS doesn't sequence to approach mode, execute missed approach or request alternate approach

    Common wrong answers

    • Not knowing sensitivity changes automatically at specific triggers
    • Not verifying the GPS is in approach mode before the FAF
    • Thinking full-scale deflection is the same for all modes

    SourceAIM 1-1-18; FAA-H-8083-16B; PilotsCafe IFR Quick-Review p.16

15. Question 15 · IR.II.A.K1

    What does the IFR equipment acronym GRAB CARD stand for, and what regulation requires it?

    What a DPE expects to hear

    • G — Generator/alternator
    • R — Radio: communications appropriate to route
    • A — Altimeter (sensitive)
    • B — Ball (inclinometer/slip-skid indicator)
    • C — Clock (or approved elapsed timer)
    • A — Attitude indicator
    • R — Rate-of-turn indicator (TC or turn-and-bank)
    • D — Directional gyro (heading indicator)
    • Required by 14 CFR §91.205(d) for IFR flight

    Common wrong answers

    • Forgetting the generator/alternator requirement
    • Listing DME or transponder as mandatory for all IFR (they are altitude-specific or Class A)
    • Confusing GRAB CARD with VFR day (ATOMATOFLAMES) equipment

    Source14 CFR §91.205(d)

16. Question 16 · IR.II.A.K2

    Explain the pitot-static system. What three instruments use it and how does a blocked pitot tube affect each?

    What a DPE expects to hear

    • Pitot tube measures impact (ram) air pressure; static port measures ambient atmospheric pressure
    • Instruments: Airspeed Indicator (pitot + static), Altimeter (static only), VSI (static only)
    • Blocked pitot tube (with drain hole open): ASI reads zero — no ram air entering
    • Blocked pitot tube (drain hole also blocked): ASI acts like altimeter — reads high if climbing, low if descending (pressure trapped)
    • Altimeter and VSI unaffected by pitot blockage — they use static only
    • Solution: pitot heat to melt ice blockage

    Common wrong answers

    • Thinking altimeter fails when pitot is blocked
    • Not knowing about the drain hole distinction for pitot blockage behavior
    • Confusing pitot blockage with static blockage

    SourceFAA-H-8083-15B (IFH) Chapter 5; PilotsCafe IFR Quick-Review p.11

17. Question 17 · IR.II.A.K2

    What happens to the altimeter, VSI, and airspeed indicator when the static port is completely blocked?

    What a DPE expects to hear

    • Altimeter: freezes at the altitude where blockage occurred — will not change even if you climb or descend
    • VSI: reads zero — no pressure differential can develop
    • ASI: may over-read or under-read depending on altitude change; reads higher than actual if you descend (static pressure trapped is lower than ambient), lower than actual if you climb
    • Alternate static source (if available): opens to cabin air — typically slightly lower pressure than outside, causing altimeter to read slightly high, ASI to read slightly fast, VSI to show brief momentary climb
    • Emergency: break the VSI glass — connects static system to cabin air

    Common wrong answers

    • Thinking static blockage only affects the altimeter
    • Not knowing about alternate static source pressure effects
    • Forgetting the VSI glass break option

    SourceFAA-H-8083-15B (IFH) Chapter 5; PilotsCafe IFR Quick-Review p.11

18. Question 18 · IR.II.A.K2

    Describe the magnetic compass errors summarized by DV MONA.

    What a DPE expects to hear

    • D — Deviation: error caused by aircraft magnetic fields; corrected by compass swing (correction card in cockpit)
    • V — Variation: angular difference between true north and magnetic north; corrected using isogonic lines
    • M — Magnetic dip: compass card tilts toward closer magnetic pole; source of turning and acceleration errors
    • O — Oscillation: compass swings and is difficult to read in turbulence
    • N — Northerly turning error: in the northern hemisphere, compass LAGS when turning from north, LEADS when turning from south (Stop early when turning to north, overshoot to south)
    • A — Acceleration error: ANDS — Accelerate=North, Decelerate=South (in northern hemisphere, on east/west headings)

    Common wrong answers

    • Saying the compass leads when turning through north (it lags)
    • Forgetting that turning errors are worst near north and south headings
    • Not knowing ANDS mnemonic for acceleration error direction

    SourceFAA-H-8083-15B (IFH) Chapter 5; PilotsCafe IFR Quick-Review p.12

19. Question 19 · IR.II.B.R1

    You just departed IFR and 10 minutes into the flight your vacuum gauge drops to zero. You are in solid IMC at 5,000 feet. Walk me through what you do.

    What a DPE expects to hear

    • Identify vacuum failure: AI and HI begin to drift/show erroneous readings (AI may slowly topple, HI may precess)
    • Transition to partial-panel immediately: cover or ignore AI and HI
    • Establish attitude with: TC (turn coordinator, electric — confirms wings level), altimeter (altitude), ASI (pitch reference via airspeed trend), VSI (vertical speed)
    • Advise ATC of partial-panel condition and request lower traffic/priority handling
    • Set transponder to 7700 if declaring emergency or 7600 for comm issues — here continue normal comms
    • Fly to nearest suitable airport; avoid complex procedures; request no-gyro approach or PAR if available
    • Aircraft-specific: AI and HI vacuum-powered on C172N and PA-28; G1000 aircraft use AHRS — not affected by vacuum failure

    Common wrong answers

    • Thinking TC is vacuum-powered (it's electric)
    • Continuing the planned flight without declaring any advisory to ATC
    • Not knowing to cover the failed AI and HI to avoid fixating on them

    Source14 CFR §91.185; FAA-H-8083-15B (IFH) Chapter 6; PilotsCafe IFR Quick-Review p.11

20. Question 20 · IR.II.B.R1

    You are flying IFR in IMC. Midway through the flight the alternator/generator light illuminates. You don't know how long it has been on. What do you do?

    What a DPE expects to hear

    • Verify the failure: check ammeter — if showing discharge, alternator has failed; battery is now the only power source
    • Reduce electrical load immediately: turn off non-essential avionics, lights, autopilot
    • Declare emergency (Mayday or PAN-PAN) or at minimum advisory to ATC — inform of electrical issue
    • Calculate battery endurance: typical aircraft battery 20-30 minutes at reduced load — plan accordingly
    • Navigate to nearest suitable airport for landing
    • G1000: use PFD essential bus; some aircraft have essential bus that maintains PFD and one COM
    • Consider squawking 7700 if declaring emergency; 7600 if comms lost
    • Keep trying all frequencies; communicate on 121.5 if primary freq unavailable

    Common wrong answers

    • Continuing to destination without assessing battery endurance
    • Not knowing to reduce electrical load
    • Forgetting that G1000 essential bus keeps PFD + 1 COM running even on battery

    Source14 CFR §91.185; FAA-H-8083-15B (IFH) Chapter 9; AC 91-74B

21. Question 21 · IR.II.A.K3

    What is RAIM and why does it matter for IFR GPS approaches?

    What a DPE expects to hear

    • RAIM = Receiver Autonomous Integrity Monitoring
    • GPS receiver self-monitors integrity of the satellite signal: determines if the position solution is trustworthy
    • Requires at least 5 satellites for detection; 6 for fault exclusion (FDE)
    • Must check RAIM availability before an IFR GPS approach — if RAIM is unavailable at ETA, approach is not authorized
    • RAIM prediction available via: Garmin RAIM prediction tool, ForeFlight, FAA SAPT, NOTAMs (GPS advisory)
    • If RAIM fails during an approach: missed approach immediately — navigation may not be reliable
    • WAAS GPS does not rely on RAIM in the same way — SBAS provides external integrity monitoring

    Common wrong answers

    • Thinking WAAS also uses RAIM (WAAS uses SBAS/external integrity instead)
    • Not checking RAIM before an IFR GPS approach
    • Not knowing the satellite counts for detection vs. fault exclusion

    SourceAIM 1-1-17; FAA-H-8083-15B (IFH) Chapter 2

22. Question 22 · IR.II.A.K3

    What is the difference between WAAS and non-WAAS GPS for IFR approaches?

    What a DPE expects to hear

    • Non-WAAS GPS: authorized for RNAV (GPS) approaches to LNAV and LP minimums only; uses RAIM for integrity
    • WAAS GPS: uses SBAS (Satellite Based Augmentation System) ground stations to correct for ionospheric delay and improve accuracy; authorized for LNAV, LNAV/VNAV, LPV, and LP minimums
    • LPV (Localizer Performance with Vertical guidance): WAAS-only; DA as low as 200 ft / 1/2 SM; satisfies precision approach task on ACS (FAA-S-ACS-8C change)
    • WAAS provides both lateral and vertical guidance with ILS-like accuracy on LPV approaches
    • Key planning difference: non-WAAS GPS — destination OR alternate must have conventional approach

    Common wrong answers

    • Thinking non-WAAS GPS can fly LPV approaches
    • Believing any RNAV approach can be used as a precision approach without WAAS
    • Confusing WAAS accuracy with ILS accuracy on all approaches (only LPV compares to ILS)

    SourceAIM 1-1-18; FAA-S-ACS-8C; PilotsCafe IFR Quick-Review p.13

23. Question 23 · IR.II.A.K1

    What are the VOR receiver check requirements for IFR flight under §91.171?

    What a DPE expects to hear

    • VOR must be checked within 30 days preceding the IFR flight
    • Methods and tolerances (mnemonic DEPS): VOT (±4°), Ground checkpoint (±4°), Airborne checkpoint (±6°), Dual VOR check (±4° between receivers)
    • Required logbook entry: Date, Place, Bearing error, Signature of PIC
    • VOT: tune the VOT frequency; correct indication is 0° TO (or 180° FROM). Must be within ±4°
    • Ground checkpoint: fly over a specific ground point published in the A/FD; check indicated bearing matches published bearing
    • If no VOT or ground checkpoint available, may select own prominent ground point and fly over it

    Common wrong answers

    • Thinking a 30-day check is optional for IFR
    • Not knowing the ±4° vs ±6° distinction by method
    • Forgetting all 4 elements of the logbook entry (DEPS)

    Source14 CFR §91.171; PilotsCafe IFR Quick-Review p.5

24. Question 24 · IR.II.A.K1

    What is the IFR equipment required by §91.205(d)? Use GRAB CARD.

    What a DPE expects to hear

    • G — Generator or alternator (electrical power source)
    • R — Radio: 2-way radio communication AND navigation equipment appropriate to the route
    • A — Altimeter (adjustable/sensitive barometric altimeter)
    • B — Ball (inclinometer — the slip-skid indicator, part of the turn coordinator or separate)
    • C — Clock (or approved timing device with hours, minutes, seconds — stopwatch acceptable)
    • A — Attitude indicator (gyroscopic)
    • R — Rate-of-turn indicator (gyroscopic — TC or turn-and-bank indicator)
    • D — Directional gyro (heading indicator)
    • Plus VFR day equipment (§91.205(b)) plus VFR night equipment if night IFR

    Common wrong answers

    • Listing GPS as required equipment (it is not required unless flying GPS-dependent routes)
    • Forgetting the generator/alternator
    • Not knowing a clock is explicitly required

    Source14 CFR §91.205(d); PilotsCafe IFR Quick-Review p.12

25. Question 25 · IR.II.A.K2

    Your GPS database expired 5 days ago. Can you use your GPS for IFR navigation? Can you fly an IFR GPS approach?

    What a DPE expects to hear

    • Expired database — navigation: per AIM 1-1-17, you CAN use GPS for IFR en-route navigation with an expired database IF you verify that the navigation points (waypoints, airways) being used are still valid and unchanged against current FAA data
    • Expired database — approaches: CANNOT fly an instrument approach procedure (RNAV/GPS approach) with an expired database — AIM 1-1-17 explicitly prohibits this
    • Reason: approach databases are safety-critical; a changed waypoint or minimums on an approach could cause CFIT
    • Practical implication: with expired database, GPS can only be used for supplemental navigation along published airways that you verify are unchanged
    • Best practice: always update database before IFR flight; expired database creates significant operational limitations
    • Reference: AIM 1-1-17 (a)(1) — database currency requirement

    Common wrong answers

    • Thinking expired database prevents all GPS use
    • Thinking an updated tablet database covers the approach prohibition for the panel GPS
    • Not knowing approaches are specifically prohibited with expired database

    SourceAIM 1-1-17; PilotsCafe IFR Quick-Review p.12-13

26. Question 26 · IR.II.A.K2

    What is the difference between a primary and supporting instrument in instrument flight?

    What a DPE expects to hear

    • Primary instrument: the instrument that gives the most direct indication of the parameter being controlled at a given moment
    • Supporting instruments: provide backup and trend information — confirm what the primary shows
    • For attitude: when maintaining straight-and-level, the AI (attitude indicator) is primary for pitch and bank
    • For altitude: during level flight, the ALTIMETER is primary for altitude; VSI is supporting
    • For heading: the DI (directional gyro / HSI) is primary for heading during straight flight
    • During instrument scan, primary instruments change depending on the phase of flight — e.g., during a turn, TC becomes primary for bank
    • The importance: if primary fails, the student must shift to supporting — partial panel is essentially losing a primary

    Common wrong answers

    • Thinking the AI is always primary (it changes by phase of flight)
    • Confusing primary-supporting with primary-secondary (different instrument categories)
    • Not knowing which instruments become primary on partial panel

    SourceFAA-H-8083-15B (IFH) Chapter 6

27. Question 27 · IR.II.A.K2

    You are flying straight-and-level IFR in your C172N. The AI shows a 20-degree right bank but the TC ball is centered and the TC shows wings level. Which instrument do you trust and why?

    What a DPE expects to hear

    • Trust the TC (turn coordinator): the AI is showing a 20-degree bank but the TC shows wings level — these instruments conflict
    • TC is electrically powered (on most aircraft); AI is vacuum powered
    • A vacuum pump failure or AI tumble could cause the AI to show a false bank while the aircraft is actually wings level
    • TC corroboration with ball: the slip/skid ball is centered AND TC shows wings level → two instruments agree → trust TC over AI
    • Also check: altimeter (is altitude changing?), ASI (is airspeed changing?), compass (is heading changing?) — all would change in a sustained bank
    • If all other instruments agree with TC: AI has failed or is tumbling — cover it and fly partial panel
    • Cover a failed AI to avoid fixating on its false reading

    How a DPE follows up

    • If you saySays trust the AI

      DPE follow-upIf the vacuum system failed and the AI is tumbling, what other instruments can confirm actual bank angle?

      What it testsCross-checking technique — TC, ball, altimeter, ASI all provide bank/attitude information

    • If you sayCorrectly trusts TC, covers the AI

      DPE follow-upNow you are on partial panel. You need to fly an approach — what approach type has the lowest workload?

      What it testsILS is generally best for partial panel due to continuous glideslope guidance

    SourceFAA-H-8083-15B (IFH) Chapter 6; PilotsCafe IFR Quick-Review p.11

28. Question 28 · IR.II.A.K1

    What is the pitot heat requirement for IFR flight?

    What a DPE expects to hear

    • §91.205(d) requires IFR equipment — this includes the ASI which depends on pitot
    • No specific FAR mandates pitot heat be FUNCTIONAL for IFR, but if pitot heat is required by the POH for flight into known or potential icing conditions: it must be operable
    • If pitot heat is listed on the aircraft's MEL or KOEL as required for IFR: it must work
    • Practical: for most training aircraft, pitot heat is a strong recommendation — its inoperability with icing forecast could make the aircraft unairworthy for IFR in icing conditions
    • §91.213: inoperative equipment must be assessed — if pitot heat failure means icing could block the pitot system and render the ASI inoperative: the aircraft may be unairworthy for IFR in potential icing
    • Check your aircraft's POH Kinds of Operations and MEL for specific requirements

    Common wrong answers

    • Thinking pitot heat is always explicitly required by FAR for all IFR
    • Not checking the POH's Kinds of Operations section
    • Ignoring pitot heat failure when icing is forecast

    Source14 CFR §91.205; 14 CFR §91.213; POH Section 2

29. Question 29 · IR.II.A.K3

    What equipment is required to fly in RVSM airspace (between FL290 and FL410)?

    What a DPE expects to hear

    • RVSM = Reduced Vertical Separation Minima — 1,000-foot vertical separation FL290 to FL410
    • Required equipment per §91.180 and AC 91-85B:
    • Two independent altitude measurement systems (two altimeters)
    • An altitude alerting system
    • An automatic altitude control system (autopilot with altitude hold)
    • A secondary surveillance radar (SSR) transponder (Mode C or Mode S with altitude reporting)
    • The aircraft must be RVSM-approved and the operator must have Letter of Authorization (LOA) or equivalent
    • Part 91 operators require a Letter of Authorization (LOA) from the FAA for RVSM operations
    • If RVSM equipment fails en-route: must advise ATC immediately and may be assigned non-RVSM altitudes

    Common wrong answers

    • Thinking any aircraft can fly RVSM if at FL290
    • Not knowing the autopilot altitude hold requirement
    • Not knowing the LOA requirement for Part 91

    Source14 CFR §91.180; AC 91-85B; AIM 4-6-1