Navigation Flashcards
During FMC CDU pre-flight, VERIFY POSITION is observed - What could cause this?
Difference between entered IRS position and origin airport position is greater than 4NM.
Before operating the ILS TEST button VHF NAV control panel you should what?
Select ILS freq, course within 90 deg of aircraft heading
If all AC power is lost in fligh what will the effect be on the IRSs?
ON DC will be displayed on both, Left will run as lon as battery is available, Right will shutdown after 5 mins
What is the highest priority for FMC positioning updating?
GPS
If AC power is removed from the aircraft with the aircraft on the ground and the IRSs on battery power, what indications are given to alert groundcrew?
A horn will sound in the nose wheel well
Before operating the VOR TEST button the VHF Nav control panel, what should you do?
Select a VOR frequency and a course of 000 degrees
In the event the IRS alignment is lost inflight, what functions may be retained?
By selecting ATT and flying straight and level for 30 seconds, attitude reference is available and heading information is available if the current magnetic heading is entered.
If DC power to an IRS fails and the DC FAIL light illuminates with normal AC power to the IRSs what would be the result?
The IRS would operate normally
How would the flight crew identify a GPS failure of a single receiver?
This would be recognised on recall only when pushed (single channel failure)
How are the DME receivers tuned for position updating?
The FMC auto-tunes the DME receivers as required for position updates
How is present position normally entered into the IRS
Through the CDU but the IRS ISDU can be used as a backup
What is the significance of flashing white align light on IRS?
Generally, failure condition or not enough info, or inaccurate PP entered
