Flight Controls Flashcards
Normal Law:
Load factor limitation
The load factor is automatically limited to
- +2.5 g to -1 g, slats retracted
- +2 g to 0, slats extended
Normal Law:
Pitch attitude protection
Pitch attitude protection limits pitch attitude to:
- plus 30 °
- minus 15 °
Normal Law:
High Angle-Of-Attack protection
- When the current angle-of-attack becomes greater than αPROT, the high angle-of-attack (AOA) protection activates.
- Without pilot input, the F/CTL computers will maintain the angle-of-attack equal to αPROT.
- The AOA can be further increased by pilot input, up to a maximum value equals to αMAX.
- The αfloor will usually be triggered just after entering the αPROT
- At takeoff, the αPROT is equal to the αMAX for 8 s.*
Normal Law:
High Speed Protection
- If there is no sidestick input, the aircraft will slightly overshoot VMO/MMO and fly back towards the envelope.
- If the sidestick is maintained full forward, the aircraft will significantly overshoot VMO/MMO. At approximately VMO +16/MMO +0.04, the pitch nose-down authority smoothly reduces to zero
- With the sidestick released, the aircraft always returns to a bank angle of 0 °. The bank angle limit is reduced from 67 ° to 45 °.*
- The autopilot disconnects at VMO +12 kt and MMO + 0.03.*
Normal Law:
Low Energy Aural Alert
A low energy aural alert “SPEED SPEED SPEED” repeated every 5 s
It is available in configuration 2, 3 and full between 100 and 2 000 ft. Immediately before ALPHA floor.
The low energy aural alert is computed by the PRIM’s from the following inputs: ‐ Aircraft configuration
- Air speed deceleration rate
- Flight path angle
It is inhibited when:
- TOGA is selected
- Below 100 ft RA
- Above 2 000 ft RA
- Alpha floor or GPWS alert is triggered
- In alternate or direct law
- If both RA are failed
For example, if the aircraft decelerates at 1 kt/sec, and:
- The FPA is -3 °, the alert will trigger at +- VLS -8,
- The FPA is -4 °, the alert will trigger at +- VLS -2.
Normal Law:
Bank Angle Protection
- If the pilot releases the sidestick at a bank angle greater than 33 °, the bank angle automatically reduces to 33 °
- If the pilot holds full lateral sidestick deflection, the bank angle goes to 67 ° and no further.
- If the bank angle exceeds 45 °, the autopilot disconnects and the FD bars disappear. The FD bars return when the bank angle decreases to less than 40 °.
- If angle-of-attack protection, or high speed protection, or negative pitch attitude protection is operative, the bank angle will not go beyond 45 °*
- If high speed protection is operative, the system maintains positive spiral static stability from a bank angle of 0 °*
Normal Law:
Maneuver Load Alleviation (MLA)
Becomes active when…
The MLA becomes active when the sidestick is pulled more than 8 °, and the load factor is more than 2 g, in which case :
- The ailerons are symmetrically-deflected upwards (Maximum of 11 ° is added to roll demand, if any.)
- Spoilers 4, 5, 6 are symmetrically-deflected (Maximum of 9 ° is added to roll demand, if any, Deflection is proportional to load factor, in excess of 2 g.)
- An elevator demand is simultaneously applied to compensate for the pitching moment induced by spoilers and ailerons.
The load alleviation is only available, when :
- The aircraft speed is above 250 kt.
- The FLAPS lever is in the 0 position.
- In normal or alternate law flight mode.
Normal Law:
Turbulence Damping Function
It is only available if the following conditions are met :
- Aircraft in flight.
- Aircraft speed greater than 200 kt.
- Autopilot engaged or normal law active.
- Aircraft within the normal flight envelope.
Normal Law:
Aircraft Trimming (rudder)
When the aircraft is :
- In normal cruise range,
- In straight flight,
- With the autopilot engaged,
- With symmetrical engine thrust, and
- With fuel in the wing tanks distributed symmetrically,
The rudder trim should stay between … ° right and … ° left.
- The rudder trim should stay between 1.9 ° right and 1.6 ° left.
Alternate Law
Load factor limitation
The load factor is automatically limited to
- +2.5 g to -1 g, slats retracted
- +2 g to 0, slats extended
Alternate Law:
Pitch attitude protection
Not available
Alternate Law:
High Angle-Of-Attack protection
Low Speed Stability
- VLS remains, but Vα PROT and Vα MAX disappear, replaced by a single black and red strip, the top of which is stall warning speed.
- Unlike VLS, which is stable, VSW is g sensitive so as to give additional margin in turns. ALTERNATE reverts to FLARE law for landing at 100 ft.
- At low speed, a nose down demand is introduced in reference to IAS
- It is available, whatever the slats/flaps configuration, and it is active from +- 5 kt up to +- 10 kt above the VSW, depending on the aircraft’s weight and slats/flaps configuration.
- A gentle progressive nose down signal is introduced, which tends to keep the speed from falling below these values. The pilot can override this demand.
- In addition, aural stall alert (“STALL, STALL” synthetic voice then cricket) is triggered at an appropriate margin from the stall condition.
ALPHA floor is not available
Alternate Law:
High Speed Protection
High Speed Stability
- Above VMO/MMO, a nose up demand is introduced to avoid an excessive increase in speed. The pilot can override this demand.
- The high speed protection symbol (VMO + 4) disappears.
- The overspeed warning (VMO + 4 or MMO + 0.006) remains available.
VMO is changed to 0.82
Alternate Law:
Low Energy Aural Alert
Alternate Law:
Bank Angle Protection
Not available
Bank angle limitation remains effective in ALT 1, which uses roll normal.
However, since ALT 1 is generally an unprotected law, all protection marks on the PFD are in amber for simplicity.
