NAVIGATION Flashcards
What battery backs up the IRS if the AC POWER fails?
APU BATT
What is the longest the IRS can go without full alignment?
18 hours
Where you can find time to remain for alignment for the IRS?
Top left corner of ND
What degree of error will give you the IRS POS/ORIGIN DISAGREE message on the FMC?
Position >6nm from origin airport
How long does alignment wait after IRS motion stops?
30 sec
What does the IRS do above 84N or 84S?
Goes into SPLIT IRS OPERATION:
Each FMC connects to a different IRU. This could also happen if there are large differences between IRU’s
BAT ON (IRS maint panel)
IRS running on bat power, horn sounds
> IRS AC CENTER, LEFT, RIGHT
IRU AC power has failed
> IRS D.C. LEFT, RIGHT, CENTER
IRS operating on AC power only, no backup
IRS LEFT, RIGHT, CENTER
All power to IRS Is lost, alignment lost and cannot be restored for the flight for navigation , however it can be used for basic attitude info.
If you see IRU (C) on the Capt ND, what does that mean?
FMC auto switched to IRU CENTER. For heading data
The PFD still uses the left IRU so you must switch IRU to left
IRS MOTION
Airplane motion detected during alignment
> SINGLE SOURCE ILS
Both PFD using the same ILS source
Two ILS systems failed
Be careful with monitoring
> TRANSPONDER L,R
Transponder is failed
IRS CENTER, LEFT, RIGHT
IRU fault occurs
> GPS
Both GPS receivers are failed
> GPS LEFT, RIGHT
One GPS receiver has failed
ILS ANTENNA
An ILS receiver does not use the correct antenna
Failed to switch when gear was lowered
> FMC MESSAGE
An alert message in the CDU scratchpad (see QRH)
> FMC RUNWAY DIS
Airplane not on the FMC origin runway when takeoff is attempted
ADS-B FAILURE
One or more of these occurs:
ATC reports ADS-B Out is lost or degraded
> GPS left is shown and left xpndr selected
> GPS RIGHT is shown and right xpndr selected.
FMC LEFT, RIGHT
If a single FMC fails, can you still use the auto throttle?
An FMC is failed
Yes
What does PARK mean on the NAVRAD ILS tuning page?
ILS receivers are untuned
This is displayed til 200 MN from TOD or more than halfway to the destination.
After that it loads the fest ILS freq with Park til it is tuned auto or man
When does auto tune happen for the arrival navaid?
50nm from TOD
150nm from threshold
FMC changes to descent mode
It will show a “a” when auto tuned
When a < it means you can manually tune the frequency “M” appears
When is ILS tuning inhibited?
How can you Re-enable ILS tuning?
Below 500’
On the ground:
Loc alive
<45 deg of front course
GS >40 knots
Within 10’min after TO or when ILS manually tuned
Hitting TOGA switches
Disc AP, turn off FD switches
When viewing the CDU for VOR tuning codes, what do the following codes mean?
A
R
P
M
Auto
Route
Procedure
Manual
Manual freq remains tuned til deleted
Delete key to return
What do the following code mean after a tuned ADF on the CDU?
ANT
BFO
Antenna
BEAT FREQUENCY OSCILLATOR
You can enter the first letter instead
When does the nav system automatically go from mag to true heading?
When is grid heading displayed on the ND?
Above 80 deg lat
Above 70 deg lat (true heading and long values)
If both FMC fail, the CDU’s can still generate a map display
True or false?
True
With a dual FMC failure are the maps on both NDs the same info and sychronized?
No, each CDU creates a map for its respective side.
> SOURCE SELECT NAV
Both ND’s are using the same nav source
Both pilots ranged must be the same otherwise the route will only display on the Capt side.
If left with a disagree message too long the FO ND goes blank with a MAP in yellow displayed. Reactivate by turning to correct range.
With dual FMC failure which CDU tune which radios?
On side their respective sides only
Only numerical freq allowed.
If you get cleared to an altitude and your altitude restrictions are no longer needed how can you delete the intermediate alt constraints besides pushing the alt intervention button?
Use CLB DIR function to clear all climb constraints
How can you evaluate a down route waypoint for fuel and ETA that is not displayed on the progress page?
How can you evaluate an alternate airport from present position in the progress page?
Same for both. At the line that shows the destination, replace it with the waypoint or alternate airport
Delete when finished
Where can you find time and distance to level off in drift down?
Prog page 1, bottom right where step climb info normally is
What does FUEL DISAGREE - PROG2 mean on the FMC scratchpad?
There is a difference between totalizer and calculated of more than 4080 kgs
Determine which is more accurate and select it.
Where is the most convenient location to find all the info needed for a position report?
progress page 1, tap the position report key
After you disable GPS NAV input into the FMC composite position, what does the PURGE key do?
It eliminates the erroneous nav data you disabled from the composite, using only IRS position.
How do you create a longitude/tattitude crossing point on your route?
How do you do multiple reporting points every so many degrees?
Enter the data like this W144
For multiple do W144-4 (that would be every 4 deg of long)
How do you remove and offset?
Enter a 0 or delete or direct to a point
Up to how long after departure can you still select DEP/ARR and still get the arrival page for your departure point?
How would you do an air turn back in that case?
400nm from the departure point or halfway to your destination if route was less distance than 400 nm
Select DEP/ARR, your dep airport comes up with arrivals and app. Select and execute. Your flight plan automatically changes destination in RTE page.
How do you create a visual app?
Dep/ARR, select rwy, select VFR Appr: this creates a 8nm waypoint at 3deg
You can fly it LNAV VNAV
What does the DESC DIR function do on the descent page of the FMC?
Deletes all altitude restrictions on the descent
Using the OFFPATH DES feature, where does the airplane have to be in order to safely make the descent to the selected end of descent point?
(You must hit display to show the clean and drag circles)
Inside the clean and outside the drag at IDLE THRUST AND SPEEDBRAKES EXTENDED!!
If outside the clean circle then a clean descent is possible.
Once inside the drag circle, a descent to that point is not possible!!!
(There is mileage to drag circle to tell you how much mileage you have til you can accept it any longer or need delay vectors to stay out of the drag circle.)
What does the effect of being 1 min off on your clock accuracy for longitudinal separation between aircraft?
8nm
If you cannot maintain your clearance in oceanic airspace what is your contingency procedure?
If unable to maintain altitude?
Diverting across tracks?
Turn 45 deg left or right, offset 15nm and then descend or climb 500’
Same procedure but while turning 45 deg begin descent.
Turn in direction of alternate and acquire offset.
Then climb or descend to take you away from RVSM and to your alternate. Reference JEPPS for alt procedure
How many GOS do we have for navigation?
2
