Avionics Flashcards
What is the normal heading source for each DBDI in flight?
The on-side IRS (IRS 1 - left, IRS 2 - right)
What is the backup heading source for each DBDI in flight?
IRS #3, indicated by a green “AHDG” indication on each DBDI
What is indicated by a “999” indication in the speed window on the flight guidance panel?
No valid auto-speed target is available
What is the default power-up heading source for each DBDI?
The flux valve (magnetic compass), indicated by an amber “STBY” on each DBDI
What is the normal order of the FMS pre-departure flow?
- NAV IDENT
- POS INIT
- FLIGHT PLAN
- PERF INIT / PERFORMANCE DATA
- DEPARTURE
- TAKEOFF INIT / TAKEOFF DATA
From where do the data acquisition units (DAUs) receive information?
- From the engine sensors
- Misc. aircraft systems such as fuel quantity.
When flying a “blue data” approach, what are the proper indications to show that the FMS is in approach mode?
- At 2 miles prior to the FAF / FAWP, the APRCH light must be illuminated on the CDU
- The missed approach prompt is not required but should be displayed at the 4L position on the CDU flight plan page
On a “blue data” approach, what is indicated by the illumination of the APRCH light on the FMS CDU? (4)
- FMS is the selected navigation source and
- aircraft position is 2 NM outside the FAF and the MAP on the FMS LSK 4L
- The FMS is using sensors approved for that type of approach
- A non-precision approach that is not localizer-based has been selected from the FMS navigation database
How is CDI scaling affected by the FMS in approach mode?
The CDI scaling changes from 5 NM to 1.5 NM either side of center.
(note: G-IV limitations require that all FMS approaches must be coupled to at least the flight director as the CDI does not scale to 0.3)
Is it possible to have both the DGRAD and the APRCH lights on the CDU illuminated at the same time?
No, the approach light will not be displayed if DGRAD has illuminated
After takeoff, when are the takeoff V-speeds replaced by VREF on the airspeed tape?
When accelerating above 200 knots and altitude above 400’ AGL
What conditions might cause the performance computers to delete the takeoff V-speeds after they have been “boxed” for takeoff?
Selecting DIRECT TO a waypoint on the ground
What is the sensor priority for the FMS, from highest to lowest?
GPS
DME / DME
VOR / DME
IRS
During an auto-throttle takeoff, when does the auto-throttle system go to “HOLD” mode?
At 60 knots indicated airspeed, regardless or power lever position or EPR setting
When are flight director command bars displayed on both PFDs? (3)
- TO or GA mode active
- Dual approach mode active (ILS below 1,200 feet AGL, both sides have ILS selected an tuned in respective radios)
- 2 failed symbol generators with the remaining one in NORM (two failed in ALT)
