NotesQuestions
0/100 correct
INSTRUMENTATION — CH.22

Electronic Flight Information SystemsNavigation — Instrumentation — DGCA CPL practice questions

Question 1 of 10

The yellow "RA" symbol appears in place of the normal radio altitude display when:

A.The selected radio altitude has been reached
B.The radio altitude needs re-setting on the EHSI
C.There is a failure of the radio altimeter
D.The aircraft descends below 1000 ft AGL

All 10 questions — Electronic Flight Information Systems

Navigation — Instrumentation · DGCA CPL. The correct option is marked on each.

  1. Q1. The yellow "RA" symbol appears in place of the normal radio altitude display when:

    • A.The selected radio altitude has been reached
    • B.The radio altitude needs re-setting on the EHSI
    • C.There is a failure of the radio altimeter✓
    • D.The aircraft descends below 1000 ft AGL

    Why: Yellow flags/text on EFIS indicate faults or failure. A yellow "RA" flag means the radio altimeter data signal has failed — the RA display has been replaced by a yellow failure flag annunciation.

  2. Q2. When using EHSI, weather radar may be displayed on the following settings:

    • A.Map, VOR/ILS
    • B.VOR/ILS, Map, Expanded Plan
    • C.Expanded Map, VOR/ILS, Plan
    • D.Map, Expanded VOR/ILS✓

    Why: WXR is available on: MAP mode and EXPANDED VOR/ILS modes. WXR is NOT available on: Full VOR, Full ILS (full compass rose), or PLAN mode (inhibited). The key rule: WXR requires the expanded arc presentation or map mode — not the full compass rose or plan. Memory tip: "Full compass = no weather." In full VOR/ILS mode the full compass rose takes up all the space. WXR data only overlays on the expanded arc or map background.

  3. Q3. WXR display is controlled from:

    • A.Captain's EHSI control only
    • B.Co-pilot's EHSI control only
    • C.A special control panel
    • D.Both captain's and co-pilot's EHSI control panels✓

    Why: EFIS is a two-sided system — Captain and First Officer each have their own EHSI control panel. WXR can be selected on/off from either pilot's EHSI control panel independently. Both CRTs can display weather radar simultaneously.

  4. Q4. Decision height is adjusted and set on the:

    • A.Flight management computer
    • B.HSI section of the EFIS control panel
    • C.ADI section of the EFIS control panel✓
    • D.ADI or HSI

    Why: Decision Height is displayed on the EADI (ADI) — the attitude indicator — not the HSI/EHSI (navigation display). Therefore the DH SEL (Decision Height Selector) is on the ADI/EADI section of the EFIS control panel.

  5. Q5. Weather may be displayed, with modern EFIS, on:

    • A.The captain's CRT only
    • B.The co-pilot's CRT only
    • C.A special screen
    • D.On both the captain's and co-pilot's CRTs✓

    Why: Both the captain's and co-pilot's EHSI control panels have a WXR switch. Weather radar data can be displayed on both EHSI (ND) displays simultaneously. No special dedicated WXR screen is needed.

  6. Q6. Airspeed is shown:

    • A.Only on the captain's EHSI
    • B.On both EADIs✓
    • C.On both EHSIs
    • D.Only on the flight management CRT

    Why: Airspeed (as part of speed error scale and ground speed) is displayed on the EADI (attitude indicator / PFD) — not on the EHSI (navigation display). Both captain's and first officer's EADIs display airspeed-related information.

  7. Q7. With EFIS using IRS guidance, reference north can be:

    • A.Magnetic north only
    • B.Magnetic north between 73°N and 65°S, and true north above these latitudes✓
    • C.Magnetic north between 65°N and 73°S and true north above these latitudes
    • D.Magnetic north between 75°N and 75°S and true north above these latitudes

    Why: The compass rose automatically references to magnetic north when between latitudes 73°N and 65°S , and switches to true north above these latitudes (where magnetic variation becomes extreme and unreliable). The crew may also manually select TRUE at any latitude. Note the asymmetry: 73°N but only 65°S. This reflects real magnetic variation geography — the magnetic anomaly is more severe in the northern polar regions.

  8. Q8. Modes available for EFIS HSI on some units are:

    • A.Airspeed and Mach
    • B.MAP and PLAN✓
    • C.VOR, ILS, MAP and AUTO TRIM
    • D.Only from manometric sources

    Why: The four modes of the EHSI are VOR, ILS, MAP and PLAN. The question asks specifically about "some units" — MAP and PLAN are the two modes that require FMS data and are available only on equipped systems. VOR, ILS, MAP, and PLAN are the four standard modes. Answer B (MAP and PLAN) is what distinguishes this EHSI from a basic HSI.

  9. Q9. The EFIS symbols for a navaid and en route waypoint are: (choose C)

    • A.Option A
    • B.Option B
    • C.Navaid = circle/diamond shape (green when tuned, cyan when untuned); Waypoint = star shape (magenta when active, white when inactive)✓
    • D.Option D

    Why: Navaids use a circle or diamond symbol (green when tuned, cyan when unused). Waypoints use a star/asterisk symbol (magenta = active/current waypoint the aircraft is navigating to; white = inactive waypoint on active route; cyan = off-route waypoint).

  10. Q10. An EFIS installation as well as having a control panel, symbol generators and a remote light sensor also has:

    • A.EADIs and EHSIs✓
    • B.EHSIs and altitude indicator
    • C.EADIs and EICAs
    • D.EADI and WXR display tubes

    Why: The five components of each EFIS system are: EADI (or PFD), EHSI (or ND), control panel, symbol generator, and remote light sensor. Therefore if you're given control panel + SG + remote light sensor, the missing components are EADI and EHSI.