Autoland Flashcards
How many frequencies does an ILS ground system work on?
2
What kind of frequency is used for the localiser?
VHF or metric
What kind of frequency is used for the glide-slope?
UHF or decimetric
How is the approach started?
With HDG SEL or LNAV engaged on an intercept course for the localiser
What is required before APP can be selected?
One Nav receiver must be selected to an ILS frequency or if a DUAL approach both receivers must be tuned
What happens after APP is selected on the MCP?
VOR LOC and G/S show in white as armed on the FMA
What can be done once APP has been selected?
The second autopilot can be selected.
If a second autopilot is selected when will it engage?
When the glideslope and localiser are captured and the aircraft is below 1500ft
What does the PFD display before the second autopilot is engaged?
SINGLE CH
What does the PFD display after the second autopilot is engaged?
CMD
When is the autoland status display frozen?
Below 200ft RA, except that NO AUTOLAND may illuminate
What is the name given to an autopilot system with 3 autopilots where one might be voted out if it fails?
A fail operational or fail active system.
What will happen in a system with two autopilots if one of them fails on an automatic ILS approach?
Both autopilots will disengage and the aircraft will be left in a trimmed state. Know as fail passive
How can a two autopilot system be made “fail operational”?
By adding an external monitoring and comparisons system which can identify and disconnect the failed autopilot.
What must be done after a “fail passive” autoland?
Autoland must be discontinued and the manual landing carried out