Flight Controls Questions Flashcards
(25 cards)
What are the flight control laws?
Normal Law
Alternate Law (with & without protections)
Direct Law
Abnormal Attitude Law
Mechanical Backup
What is the purpose of mechanical backup?
To achieve all safety objectives in the MMEL dispatch condition, to manage a temporary and total electrical loss, the total loss of 5 fly by wire computers, the loss of both elevators or the total loss of ailerons and spoilers.
What is the purpose of the abnormal attitude law?
Designed to modify the flight control laws when the aircraft goes far beyond the normal flight envelope and reaches an extreme attitude. Allows the PF to have maximum efficiency to recover normal attitude.
In normal law, explain the bank angle protections?
System maintains positive spiral static stability for bank angles above 33 degrees. If crew releases sidestick beyond that angle of bank, aircraft will return to 33 degrees.
If AOA protection is active, flight crew maintains full deflection on sidestick, the AOB will not go beyond 45 degrees.
If high speed protection is active, full deflection, AOB will not go beyond 40 degrees. Positive spiral static stability back to 0 degrees when sidestick is released.
No autotrim in bank angle protection.
If bank angle exceeds 45 degrees, FD’s will disappear and return when bank angle is less than 40 degrees.
What is the max bank angle when alpha protection is in force? What is the max bank angle when high speed protection is in force?
Alpha Protection: 45 degrees
High Speed Protection: 40 degrees
When in alpha protection, what happens when you release the sidestick?
Aircraft will sit at aPROT and stay there.
What is the max pitch available in the clean config and config full?
Clean Config: 30 degrees (25 slow speed)
Config Full: 25 degrees (20 slow speed)
What is the max g-load in clean and other configs?
Clean: 2.5g to -1g
Other configs: 2g to 0g
Explain Alpha prot, alpha floor and alpha max?
Alpha Prot: Max AOA with stick neutral
Alpha Floor: A/THR provides TOGA to get the aircraft out of the low speed state.
Alpha Max: Max AOA with sidestick fully aft.
Once out of alpha floor condition, what thrust mode do you expect to see and how would you recover?
A.FLOOR on FMA. Recover by using the auto thrust instinctive disconnect pushbuttons.
What is VLS and what is its relation to the stall speed?
VLS is the lowest selectable speed. It is a factor of the stall speed dependant on flight phase:
T/O or touch and go: 1.13 VS
After retraction of one stage: 1.23 VS
Clean Config: 1.28 VS
Can high speed protections be overridden?
Yes they can by the use of sidestick input.
Speed tape in normal law and alternate law?
Normal Law: VLS, vAprot and vAmax
Alternate Law: VLS and VSW
When you might see “USE MAN PITCH TRIM” and “MAN PITCH TRIM ONLY”
USE MAN PITCH TRIM: Direct law
MAN PITCH TRIM ONLY: Mechanical back up.
What is alpha lock and when might you see it?
Alpha Lock inhibits slat retraction at high AOA and low speeds. AOA above 8.5 or speed less than 148kts.
In alternate law, what is high and low speed stability?
High Speed: above VMO/MMO a nose up demand is introduced to avoid an excessive increase in speed.
Low Speed: Progressive nose down order to prevent speed from falling below stall warning speed. Active from 5 to 10kts above stall warning speed.
What protections do we have in direct law?
No protections.
Which control surfaces have a mechanical link to the flight deck?
Rudder pedals.
What is the purpose of aileron droop? How do you know your aircraft is fitted with it?
Used to keep the continuity of the airflow over the wing. Identified on the FCTL page as FCTL arrows moving down.
In pitch, how long does it take to transfer from GND to FLT mode on T/O?
5 seconds.
What is ground mode and what is flare mode?
Ground Mode: A direct sidestick to elevator relationship. No autotrim.
Flare Mode: THS is frozen. Flare mode is essentially a direct stick to elevator relationship. System memorises the A/C’s attitude at 50ft, and it becomes the initial reference for pitch attitude control.
What computer controls the characteristics speeds that you see on the speed tape and PFD?
FAC (Flight Augmentation Computer).
What is the low energy alert and when does it occur?
A/C’s energy level is going below a threshold under which the flight crew has to increase thrust in order to regain a positive flight path angle through pitch control.
Explain the purpose of the BETA target and when it becomes visible?
