Flight Instruments Flashcards
During normal operation which flight instruments receive information directly from the ADC?
- Airspeed indicator
- VSI
- Altimeter
What is the indication of an ADC failure?
When altitude is failed (Altimeter)
What action should be taken if an ADC fails?
Switch to the good ADC source, 1 or 2
What are the standard operating modes for the AHRS?
NORM AND SLAVE
NORM, each side receives their own attitude source:
- AHRS 1 for pilot side
- AHRS 2 for copilot side
1, both PFD’s use AHRS 1 source
2, both PFD’s use AHRS 2 source
SLAVE, flux valve establishes references to north
What are the reduced operating modes for the AHRS?
Basic and DG
Basic mode, if both TAS parameters are not available to the AHRU.
- decreased attitude accuracy
- EADI will behave like a conventional mechanical gimballed gyro.
DG mode:
- set to DG when flux valve malfunctions or during degraded performance when flying close to poles
- AHRU’s don’t receive magnetic data from flux valves in DG mode
What is the basic mode of the AHRS?
It has no correction for acceleration. It becomes a conventional AI. This happens when the flux valve fails.
What is the indication of the low speed cue failure?
Low Speed Cue ( red and black box or “red tape) IAS removed from view. It is replaced by CUE when IAS is valid but low speed cue information is invalid.
What is the purpose of the static isolation valve?
Allows you to isolate static air data to be from just the Number 1 pitot static probe. information goes to ADC 1.
What are the indications of a Radio Altimeter mismatch?
- RAD ALT MISMATCH MESSAGE, on PMA (yellow), yellow initially flashes for 5 seconds, then stays on steady.
- RA flag (yellow) is also shown above RA digital altitude at bottom of AI
What are the indications of a radio altimeter failure (single or dual if installed?)
RAx FAIL message on ED (x=1 or 2 or S if both are concerned)
NOTE: AVIONICS caution light comes on if the airplane is on the ground for more than 2 minutes
Where is digital RAD ALT information displayed?
Below the AI, beginning at 2500 feet.
Where are the analogue (not digital) indications of the RAD ALT displayed?
Brown band on altitude tape. Shown when RA is less than 550ft.
Moves vertically, corresponding to the altitude AGL
Which display screens are available on Essential power only?
- MFD1
- ED
Also; MFD1 selector on the ESCP and the ALL push button on the ESCP
What is the only automatic screen reversion?
ED failure, if the ED fails, its image is automatically transferred to the MFD1.
How can you display system information if both MFD’s fail?
Pushing and holding down on the dedicated System page key, shows the related System page and the Permanent System Area (PSA), in composite format, on the Engine Display, replacing ENG format.
