AVIONICS Flashcards
What items do the pitot heads feed?
Airspeed indicator and ADC, on respective side.
Where does the ADC receive its pitot and static pressure from?
Pitot and static vents on their respective sides, the static ports or dual flush mounted.
What is the cockpit control center for the autopilot and flight director?
Glareshield panel which controls the FGC
What do the ADC’s supply?
Altimeters, Altitude alert, advisory display, FGC, AHRS, EFIC, XPDR, Spoilers, pressurization, PSEU, Rudder, overspeed warning.
Is information from both ADC’s always in use? How is this controlled?
Yes, each ADC supplies instruments on it’s side.
What standby instruments are the flight crew provided with?
Standby Attitude indicator, altimeter and compass
When does a failure flag appear in a main altimeter?
If the data from the ADC is invalid or power fails or there is a discrepancy between displayed altitude and ADC output.
What information does the AHRS system supply?
ATT and HDG information to instruments, ADC, FGC, and weather radar. Also the RMIs and advisory displays.
You notice a HDG flag on your EHSI and a SLAVE advisory light on the AHRS controller, what has happened and what must you do (assume EFIS aircraft)?
Magnetic heading reference is invalid form the flux valve. can use opposite side instruments by pressing HDG REV on EFIS controller. Can press DG which puts the HSI in manual mode and slave it manually to the compass.
You notice a ATT flag on your EADI and a BASIC advisory light on the AHRS controller, what has happened and what must you do (assume EFIS aircraft)?
ATT indicator will act as a conventional gyro, the TAS information from the ADC is invalid. Shallow turns should be avoided, the VG erect button can be used to re-set the gyro however only in S.L. flight.
Can the aircraft be moved during the AHRS initialization period?
the aircraft must remain stationary for 3 minutes
Are the flight guidance computers both active at all times?
The flight guidance computers both monitor the aircraft but only one is engaged at once, if one fails the other takes over.
What indication will you get if an active flight guidance computer fails?
L or R AP fail message and the other FGC will become active.
What is the radio altimeters maximum altitude indication?
2500ft
What connection is there between the yaw damper and autopilot?
The yaw damper operates with or without the autopilot, the yaw damper is separate from the autopilot however receives yaw data from the FGC.
On the AFCS controller, what is the function of the HSI SEL button?
It determines which pilots instruments supply data to the FGC.
In approach mode, can the G/S be captured before the localizer?
No, the localiser must be captured first
When the flight director is in NAV mode; where does the auto-pilot accept steering commands from?
It will follow the displayed guidance on the selected HSI
The altitude alert annunciator on the servo altimeter illuminates when the aircraft is within how many ft of the preselected altitude?
1000ft and extinguishes at 250ft remaining. If the aircraft deviates more than 250ft from selected it will also turn on.
What happens if a Symbol Generator fails? What can you do to rectify the situation?
A red cross or blank screen. The opposite side symbol generator has enough power to run both sides.
In APP mode what happens below 1200’ AGL?
if both VHF are tuned to the same ILS and both HSI in VL, then dual approach mode will be entered. if one nav receiver fails the approach can continue.
In dual couple approach mode, what happens if a navigation receiver fails?
if one nav receiver fails the approach can continue.
If you depress the GA pushbutton what happens?
The autopilot will disengage, wings level, GA, 9/12 deg NU will be commanded by the FGC on the FD.
What indication will you get of a FD failure?
FD fail message on the EHSI, all FD cues will disappear.
The Dash 8 Sperry EFIS uses how many CRT’s? What conventional instruments does EFIS replace?
4 CRT screens, replace, ATT, HSI and all Nav instruments.
How do you get a composite display on your EFIS? Do the pilots and co-pilots EFIS controllers control the operation of the weather radar?
A composite display is achieved by turning the other screen all the way to off. The weather radar is operated by its own controller but to display it on the EHSI is selected on the EFIS controller.
Who has access to the alternate static source?
Both sides via a selector, the cabin controller and the STBY ALT run off it normally.
What does the AFCS consist of?
AHRS DADC RADALT EFIS FGC
To what does the ADC supply outputs?
FGC AHRS Advisory displays EFIS Altimeters Altitude selector Autopilot
If one FGC fails what happens?
A message is displayed on the advisory panel, the AP and YD swap sides with illumination of the other side selector.
