Navigation Flashcards
Navigation
How many GPS systems are installed on the 777?
2 (L & R systems).
Which CDU page shows the GPS position?
POS REF 3/3 page (displays L & R GPS position).
How can GPS position be displayed on the ND?
By selecting POS on EFIS control panel (ND displays L & R GPS symbols by combining them into a single symbol to show position).
What does the EICAS message “GPS” indicate?
Data FM both GPS systems are is unavailable or both systems have failed.
Can GS navigation data be inhibited?
Yes (use GPS NAV prompt on the POS REF page to inhibit data).
Is the ADIRU required for GPS navigation?
No
List 4 parameters supplied by the ADIRS?
• ACFT ALT. • Airspeed. • Attitude. • HDG
and position data for the displays
What components make up the ADIRS?
• ADIRU. • SAARU (Secondary Attitude Air Reference Unit). • Air data modules.
What bus power is required to turn the ADIRU on?
Battery bus power (and ADIRU switch on).
When can the ADIRU switch be used to turn the ADIRU off?
When airspeed < 30kts.
What conditions are required for the wheel well horn to sound?
Electrical power removed FM ACFT and battery switch turned off, the hot battery bus continues to supply electrical power to the ADIRU à ON BAT light illuminates à horn in LDG gear well sounds.
When can the aircraft be moved?
When ADIRU alignment process complete.
How can the ADIRU mode be verified?
On initial power-‐up ADIRU enters align mode –> EICAS memo message ADIRU ALIGN MODE displays.
What scratchpad message would indicate a position entry error?
INERTIAL/ORIGIN DISAGREE (displays when latitude/longitude position not close to position of the origin airport).
When does the automatic realign mode occur?
If ACFT stops for an extended period of time.
What can the SAARU supply after an ADIRU failure?
• Attitude. • HDG. • Air data.
SAARU HDG must be manually set to the STBY compass magnetic HDG periodically
How long does the SAARU supply backup heading for?
3 minutes.
How will the crew know that a heading update is required?
CDU displays SET HDG prompt on the POS INIT page.
What is the pilot’s normal source for air data?
L, C & R pitot static systems.
What will provide pilot’s Air Data after failure of the ADIRU?
SAARU.
When does single channel Air Data occur?
When both ADIRU & SAARU air data invalid.
Which Air Data channel supplies the Standby Instruments?
C (Centre pitot & static ports).
Can the ADFs be tuned automatically?
No (manually only).
How are the DMEs turned manually?
When the VOR portion of a VOR/DME FREQ pair is entered on the NAV RADIO page.
After a dual FMC failure, when is the DME tuned to an ILS DME?
When the related EFIS control panel mode selector is set to APP. In APP, the DME is tuned to the ILS (if not in APP, L DME is tuned W/ VOR on L CDU, R DME is tuned W/ VOR on R CDU).
Which CDU page displays the DME stations being used for radio updating?
POS REF 2/3 displays identifiers of DME stations used for FMC position updates.
With an approach selected, when will the ILS be autotuned?
Both must be met: • ILS, LOC, back course, LDA (localizer-‐type directional aid) or SDF (simplified directional facility) APP have been selected to the active route.
• ACFT W/in 50nm FM ToD, 150nm FM LDG RWY threshold or FMC in descent mode.
During an autoland, when does ILS tuning inhibit occur?
• Autopilot engaged and either LLZ or G/S captured. • Only F/D is engaged and either LLZ or G/S is captured and ACFT is BLW 500’ RA. • On GND, LLZ is alive, ACFT HDG W/in 45o of LLZ front course and GS > 40kts.
With no inhibit, will the ILS automatically retune with selection of a new approach?
Yes (automatically retuned when ILS turning enabled and a new APP is selected on the CDU).
When should the pilots audibly verify the identification of a tuned navigation station?
When the tuned FREQ remains displayed or an incorrect identifier displays.
Does the FMC ever use a VOR/DME station for position updates?
Yes, but only when more accurate sources are not available.
How are the VOR radios tuned after a dual FMC failure?
Tuned manually on the CDU ALTN NAV RADIO page (L VOR tuned W/ LEFT CDU, R VOR tuned W/ R CDU).
Where can the VOR/DME station being used for radio updates be seen?
POS REF page 2/3 (displays identifier of VOR & DME FREQ pair used for position updates).
In flight, when will the selected transponder activate beacon and altitude report?
When transponder mode selector is in XPNDR, TA ONLY or TA/RA.
When will the transponder function for aircraft position monitoring on ground?
When transponder is active (not in off or STBY).
What other functions can be enabled for the transponder?
Transponder may transmit: • FLT number. • Airspeed. • GS. • HDG oM. • ALT. • GPS position, etc.
What EFIS modes are compatible with weather radar?
VOR (expanded), APP (expanded), MAP (expanded & centred).
Which switch controls power to the weather radar transceiver?
EFIS control panel weather radar (WXR) switch.
What type of turbulence can be detected by the weather radar?
Turbulence associated W/ precipitation (cannot sense CAT).
What type of windshear detection is available from the weather radar?
Predictive windshear alerting (PWS).
What type of advisories does TCAS provide?
• TA (TFC advisory). • RA (Resolution advisory).
What EFIS modes are compatible with TCAS displays?
MAP (centred & expanded), VOR (expanded), APP (expanded).
When will an RA be issued?
When another ACFT predicted to enter TCAS conflict airspace W/ approx.. 20-‐30s.
What is the vertical distance of proximate traffic?
1200’ (& 6nm).
How is RA traffic avoidance ensured?
By adjusting or maintaining a pitch attitude and V/S outside the red RA regions.
When should TA ONLY be selected?
During engine out operations (to prevent RAs when adequate thrust not AVBL to follow RA commands).
What are GPWS immediate alerts based upon?
RA. • Barometric ALT. • ADIRS. • G/S deviation. • ACFT configuration.
How is altitude calculated for look-‐ahead terrain alerting?
By using a worldwide terrain database.
Is estimated VNAV and LNAV path used in time to impact estimation?
No
What terrain is displayed on the ND?
All terrain W/in 2000’ of ACFT ALT.
How does selection of TERRAIN on one side and WXR on the other side affect the displays?
Each ND display updates on alternating sweeps (terrain and WX radar cannot be simultaneously displayed on the ND).
Which system displays immediate windshear alerts?
GPWS.
When are PWS alerts enabled?
• 12s after WX radar begins scanning for windshear. • BLW 1200’ RA
Does PWS require the weather radar to be switched ON?
No (WXR switch does not have to be selected).
