Navigation/Radar Flashcards
Operating modes of the FMGC’s
Dual: normal mode
both FMGC’s are synced
Single: the other FMGC has failed
indications are 1FD1 or 2FD2, OPP FMGC IN PROCESS in scratchpad, or MAP NOT AVAIL on failed side’s ND
Independent: Significant difference between FMGC’s (database validity)
INDEPENDENT OPERATION in scratchpad and amber IND light on MCDU cases
FMGC auto-tuning
provides loc guidance during takeoff roll
auto-tunes VOR and DME stations enroute to update position
auto-tunes ILS freq for approach guidance when ILS has been loaded into the flightplan
VOR and ILS information displayed on ND
VOR: switches on EFIS Panel, and when identified by the FMS, 3 letter identifier is displayed
ILS: LS pb is selected, and when identified by FMS, 4 letter identifier is displayed
Explain the function of the STBY NAV key on the RMP.
Activates standby nav, deactivates auto-tuning
MCDU rad/nav page unusable
Green light illuminates next to the key indicating activation
“R” appears next to tuned frequency
“M” for manually tuned
Explain the indications of a tuned VOR on the NDs.
o If a station has been auto tuned by the FMGCs, it will only contain the station’s three letter identifier.
o If a station has been manually tuned via the MCDU’s RAD NAV page, an underlined M appears next to the station’s three letter identifier.
• Referred to as being “Hard Tuned”
o If a station has been manually tuned via an RMP’s Standby NAV keys, an underlined R appears next to the station’s three letter identifier.
• Referred to as being “Remotely Tuned”
Explain the function of the ADIRS CDU Mode Selectors.
OFF
NAV
ATT
▪ OFF – Depowered. Both ADR and IR data unavailable.
▪ NAV – Establishes power, initiates IR alignment. Provides ADR and IR data.
▪ ATT – Provides only Attitude and Heading information, if the system loses ability to navigate.
FAST ADIRS alignment.
30 seconds to 3 minutes
Explain the operational difference between steady versus flashing IR ALIGN lights.
Steady: ADIRU operating normally in alignment mode
Flashing: excessive motion
present position not entered into MCDU
position at shutdown differs from present position entered into MCDU
Recall the meaning of the ON BAT light on the ADIRS panel.
▪ Illuminates continuously when one or more ADIRU is operating on aircraft battery power.
▪ Appears for a few seconds at the beginning of a NORMAL alignment process, when an ADIRU Mode Selector is
placed from OFF to NAV. This indicates that the respective ADIRU is capable of operating on battery power when
required.
Recall the radar’s functionality during the automatic self-test.
▪ When first turned on, the radar is fully operational and is radiating energy while performing a 45 second selftest.
▪ A warm-up period is not required.
▪ Quick self-tests are performed at the end of each radar antenna sweep.
▪ Radar system fault/malfunction indications are only displayed on the NDs.
Recall the functions of each of the radar’s MODE selector knob.
o WX+T
▪ Magenta
o TURB
o MAP
▪ Black
▪ Green
▪ Amber
o WX+T – Displays both precipitation returns and turbulence
▪ Magenta represents turbulence.
o TURB – Displays only areas of turbulence in magenta.
NOTE: ND range must be set to 40 miles or less for the display of turbulence.
o MAP – Ground mapping mode:
▪ Black – water or radar shadows.
▪ Green – ground returns.
▪ Amber – man-made structures or high terrain.
Recall the functions of the radar GAIN selector knob.
o CAL (Calibrated) – provides a predetermined beam power level.
NOTE: A manual GAIN setting is recommended above FL250
Recall the function of the GND CLTR SPRS switch.
▪ When placed to ON, eliminates the majority of ground clutter targets.
▪ Ground targets are displayed in magenta.
Recall the meaning of the radar’s Path Attenuation Compensation (PAC) indication.
o Radar attenuation has been detected (A yellow alert bar appears at the top of the NDs).
o The radar system is advising that additional weather targets beyond what is currently being displayed may be
present but cannot be viewed.
▪ In order for a PAC alert:
• GAIN selector knob must be in CAL
• Intervening (currently displayed) weather must be within 80 NM of the aircraft.
o Pilot actions would be to increase GAIN selection.
