Flight Controls Flashcards
Why are ELAC1, SEC1 and FAC1 grouped together on left FLT CTL panel?
In the emergency electrical configuration these remain operative (ESS power still available)
*FAC1 becomes inoperative when electrical supply is in a batteries-only configuration.
What happens if both ELACs fail? (4 items)
-degrade to alternate law.
-both ailerons inoperative and roll control provided by spoilers.
-elevator and THS control provided by the SECs.
-both autopilots will be inoperative.
Which SECs control which spoilers?
SEC1- spoilers 3 & 4
SEC2- spoiler 5
SEC 3- spoilers 1 & 2
What do SEC1 and SEC2 provide backup for?
Elevator and THS control should both ELACs fail.
What happens if all three SECs fail? (3 items)
-degrades to alternate law.
-speedbrakes and spoilers are all inoperative and roll is controlled by ailerons only.
-backup pitch control is lost.
If both FACs fail what happens? (4 items)
-degrades to alternate law.
-rudder controlled through pedals by mechanical connection.
-rudder trim, yaw damping and rudder limiting are lost.
-both autopilots will be inoperative.
How long must takeover pb be held to deactivate other side stick? Can it be reactivated?
40 seconds.
Yes- by pressing takeover pb on deactivated side stick.
Which hydraulic systems power which elevator servos?
Left- Blue and Green
Right- Blue and Yellow
What is the purpose of damping mode on the elevator servos?
One servo is active and the other is in damping mode- follows surface movement and is available in case of failure.
What happens in the case of dual elevator servo failure?
Servos revert to centring mode and align the elevator with the THS.
Which hydraulic systems power the THS?
Green and Yellow- independent motors power the THS screwjack.
Which hydraulic systems power the aileron servos?
Green and Blue.
One is active and one is in standby (damping).
How many servos power spoilers and what happen if one servo fails?
One servo per spoiler panel.
Should one panel fail, the corresponding panel on other wing is automatically deactivated to prevent asymmetry.
What happens to spoiler position if hydraulic pressure is lost?
Spoilers will remain at current position, or less if pushed down by aerodynamic forces.
How many hydraulic systems power rudder servos?
All 3 via independent servos.
*also via mechanical linkage between rudder pedals and servos in case of dual FAC failure (Requires at least 1 hydraulic system).