Navigation Flashcards
What components make up the navigation system?
- GPS
- Air Data Inertial Reference System (ADIRS)
- 2 VORs
- 2 DMEs
- 3 ILS
- 2 ADFs
- 2 ATC transponders
- Weather radar
- FMS
What does ADIRS calculated data include?
- Position
- Heading
- Airspeed
- Altitude
- Attitude
Where is ADIRS calculated data information sent to?
- Flight displays
- FMS
- Flight controls
- Engine controls
- Other systems requiring inertial or air data
What are the major components of the ADIRS?
- Air Data Modules ( 6 ADMs)
- Air Data Inertial Reference Unit (ADIRU)
- Secondary Attitude Air Data Reference Unit (SAARU)
An alignment of the ADIRU is the calculation of the airplane’s relationship to:
True North
During flight, can the ADIRU be realigned?
No, it cannot
In flight, what happens to the ADIRU if the switch is inadvertently positioned to OFF?
System logic prevents the ADIRU from losing power if the switch is inadvertently positioned to OFF
What happens to the ADIRU if the airplane is stopped for an extended period of time? (> 7 min. 30 sec.)
- Changes to automatic realign mode
- Refines the alignment until the airplane moves again
What happens to the ADIRU when it’s in the realign mode?
ADIRU velocity and acceleration errors reset to zero
What does the SAARU provide a secondary source of critical flight data to?
- Displays
- Flight controls
- Other systems such as the AFDC
- Provides the only source of attitude data to the Standby Attitude Indicator
If the ADIRU fails, what does the SAARU automatically supplies?
- Air Data
- Attitude data to the PFD
- 3 minutes of backup heading (SAARU bases the heading on the ADIRU’s last heading prior to failure)
What happens after the ADIRU has been failed for 3 minutes?
Backup heading is lost and heading must be set manually in the CDU POS INIT page 1/3 using the heading on the standby compass
What are the 4 VOR tuning statuses?
- Automatic
- Route
- Procedure
- Manual
How is the VOR in the route auto tuning mode tuned?
The navaid is the previous VOR or a down path VOR within 250 nm of the aircraft’s position
What are the 3 ways a VOR can be manually tuned?
- Frequency or identifier alone
- Frequency and course
- Identifier and course
ILS remains in PARK until?
- 200 nm from T/D
- More than halfway to the destination
Whichever occurs first
When does the ILS tuning status changes to A and ready to be used for approach guidance?
- Aircraft less than 50 nm from the T/D
- Aircraft less than 150 nm from the runway threshold
- FMC is in the descent mode
When do the LOC and GS pointers fill in solid magenta?
When the deviation is within 2 1/2 dots from the scale center.
How many dot deviation do the rectangles display in the expanded LOC scale display?
1/2 dot
Can ADF frequencies be tuned automatically?
No
Where is the FMS-calculated guidance primarily displayed?
- ND
- Airspeed indicator
- Altimeter
- Thrust indicators
What defines the polar regions?
- North of 82 north latitude
- Above 70 north latitude, between 80 and 130 west longitude
- South of 82 south latitude
- South of 60 south latitude, between 120 and 160 east longitude
When the FMC transition to “on approach” mode?
- FMC is in the descent phase and flaps are out of up
- The first waypoint of an active instrument or VFR approach has been sequenced
- A published missed instrument approach has been selected and incorporated in the active flight plan and the first waypoint on the published approach has been sequenced
- The aircraft is on a direct-to or intercept-to waypoint and is within 12 nm of the runway threshold
- The missed approach point is the active waypoint and the distance to go is less than 25 nm
Weather radar returns are not displayed on the ND in what modes?
- Plan
- VOR Center
- Approach Center
If the ADIRU fails, what doe the SAARU automatically provide?
- Air data
- Attitude
- 3 minutes of heading
