Autoflight Flashcards
What is the minimum height for autopilot on takeoff?
100ft AGL and at least 5s after liftoff
What is the minimum height for autopilot when using final app, VS or FPA?
250ft AGL
What is the minimum height for autopilot for circling approach?
500ft AGL
What is the minimum height for autopilot on a cat 1 ILS approach?
160ft AGL
In the FMGC, what is meant by recommended max?
Max altitude displayed in the progress page.
Lowest of the max alt that the A/C:
- Can reach with 0.3G buffet margin
- Fly in level flight at Max CRZ rating
- Maintain a V/S of 300ft/min and Max CLB thrust
- Fly a speed above Green Dot and below VMO/MMI
- Is certified at
Anti-ice is not taken into account for this computation
What is a good gross error check when calculating green dot?
Double the gross weight and add 85 (below FL200)
On some types there maybe a discrepancy between vapp on the PFD and vapp on the FMGC. Why is this?
I think because Vapp in the FMGC is based on the gross weight when the approach phase is activated, along with the wind in the PERF page whereas the Vapp on the PFD is calculated by the FAC
When is the the Auto Land light armed?
200ff AGL
Can you briefly explain the function of ground speed Mini?
Provides a constant ground speed in gusty and thermal conditions to maintain A/C energy on approach.
Vapp = VLS + 1/3 wind or VLS + 5 (whichever is higher)
GS mini baseline = Vapp - wind component
V target = baseline + ADIRS wind
If you lose 1 FMGC, what annunciation would you expect to see on the pfd 5th column and how might this affect an ND?
Loss of AP on the side of the FMGC fail, but AP on the other side will work. ND has to be set at the same range as ND on work FMGC side
What methods does the aircraft have to calculate its position?
MIX IRS position
Computed radio position
GPS Position
What is the aircraft’s FM position comprised of?
Mix of IRS/GPS position. Flight crew can also update the FM position manually
What is EPE?
Estimated Position Error
What is meant by GPS primary?
- The accuracy is High (EPU is lower than required on PROG Page)
- Capability to detect a failure and provide appropriate warning of it.
With a lose of both flight management computers? How do you recover radio navigation?
Flick the cover and press Nav button
Prior to entering the hold, what will happen when you press the immediate exit push button?
It won’t enter the hold and will resume its applicable manage speed of the current flight phase
Once you are in the hold, what will happen when you press the immediate exit push button?
It will fly to the fix and exit the hold, unless already heading inbound, it won’t finish the holding pattern.
For alternate planning, what assumptions are made to the flight level and speed by the FMGC in terms of fuel burn for the alternate?
FL100 is less than 100nm
FL200 between 100 - 200nm or else at FL310
CI0
Constant wind
Constant felt ISA
Explain the differences between the top of descent profile and geometric descent
Top of descent profile flies a managed speed
Geometric Descent flies a specific angle
Explain SRS, what is its functions?
Speed Reference System
Vertical mode that provides vertical guidance up to acceleration altitude.
As long as slats are extended and V2 is available to the FMS, SRS engages automatically when power is applied for takeoff. It commands V2 + 10 during normal ops.
If an engine fails, V2 is commanded
Maintains a minimum rate of climb without regard to speed control to provide windshear protecrion.
At thrust reduction, SRS is automatically replaced by CLB mode
Are there any protections with SRS?
Flight path protection that ensures VS of 120ft/min during takeoff
18 - 22 degrees pitch attitude in case of windshear (A319/20) 15 - 22 A321)
What would happen when selecting a revised altitude when the aircraft is in ALT*
Reverts to V/S / FPA when changed by more than 250ft
What is the 2 engine operating range of the A/THR and what is the single engine operating range?
AEI: Idle - CLB detent.
OEI: Idle - MCT
With A/THR failure, what FMA would you expect to see?
Thrust lock
If you took off in Flex, how do you achieve MCT in an engine failure on takeoff?
Back to the climb detent, then the MCT detent
What is the guidance for selecting reverse thrust with 1 thrust reverser inoperative?
In an RTO, use them as normal. On landing, use Reverse idle on both. If both are inoperative you would use idle reverse on a RTO or on landing. You only don’t use them if fuel leak.
You have both thrust levers working and in the climb detent. You move the thrust levers below the climb detent, what FMAs would you expect to see?
AUTO FLT A/THR LIMITED repeated every 5s
What is the maximum speed that you can set on the FCU?
399 kts
What is the minimum speed you can set on the FCU?
100 kts
What is the backup speed scale and when may you need to use it. Where is its data derived?
Enables you to fly A/C when airspeed indications are unreliable.
Speed is based on AOA
Altitude is based on GPS
Explain the bird and where it gets it’s data from
Indicates track and flight path angle in relation to the ground
What is meant by the phrase data lock?
700RA with APPR mode (LOC and G/S armed or engaged), the ILS freq and course are frozen in the receiver.
If speed is managed, it doesn’t accept any modification in the PERF page
What is land mode?
Comes in 400RA on an auto land, Land Mode tracks the LOC and G/S beams until approx 40RA when Flare mode engages
What failures would illuminate the auto land light?
B - Both
A - APs
L - Loss of LOC > 15’
D - Deviation from LOC/GS
G - GS Loss > 100’
R - RAD
A - ALT Discrepancy > 15ft
F - FMGS defects long flare
What is the approach ban?
Height at which an approach can’t be continued past without the required visibility minima. 1000ft RA usually
Would a failure of a single engine illuminate the auto land light?
No
What is the definition of fail operational and fail passive?
Fail Operational: in the event of a failure below alert height, the approach, flare and landing, can be completed automatically
Fail Passive: in the event of a failure, there is no significant out-of-trim condition or deviation of the flight path or attitude but the landing is not completed automatically
For runway lighting you see alternating amber and red lights on the centre line, how much runway is remaining?
900m I think but I think it’s red and white alternating
If you were to see all reds, how much runway would be remaining?
300m
What is the difference between disconnecting the A/THR via the FCU and disconnecting it via the instinctive disconnects in the thrust levers?
Main difference is THR Lock with Non-standard disconnection
FCU Failure Key Points
CAT 1
No AP
No FD
No ATHR
No TERR
No ex radar (ignore if displayed)
No FCU selections
ND stuck at 80nm
PFDs stuck on STD - use ISIS for baro and do not put MDA (MDH) into PERF page
PM to do standard call-outs (hundred above, minimums etc)
If you are in land mode when it fails, on ATHR is lost
