To avoid flying at low speed with a low thrust, the α-floor function automatically applies TOGA thrust, when the angle of attack exceeds the alpha-max threshold.
when the angle of attack exceeds the alpha-floor threshold (between alpha-prot and alpha-max). TOGA thrust is applied, regardless of the thrust lever position and the A/THR engagement status.
In addition, when the speed reaches VMO + 5 kt with a positive acceleration, or when the speed reaches VMO + 10 kt, the A/THR automatically engages and targets the airspeed bug indicated on the PFD or VMO/MMO, whichever is lower and the speedbrakes fully extend automatically.
The speedbrakes automatic extension is inhibited if the flight crew sets the sidestick half forward or beyond.
For the activation of the high speed protection, the ______ compute a load factor threshold. If a load factor lower than this threshold is commanded, the high speed protection activates.
When the high speed protection is active:
VFE NEXT is the VFE of the next more extended configuration. The aim of VFE NEXT is to remind the flight crew the maximum speed at which they can extend the next configuration during approach.
The high speed protection activates at a threshold that depends on the acceleration of the aircraft. The higher the acceleration, the earlier the threshold.
VMCG is the minimum speed on ground during takeoff at which the use of only the primary flight controls permits to control the aircraft after a sudden failure of one engine with the other engine at takeoff thrust.
The reactive windshear detection is available:
The objective of the low energy alert and of the alpha floor function is to protect the flight path angle by providing means to achieve a proper level of energy. The low energy alert is the first level of protection. It requires crew action, for manual thrust increase. The alpha floor function is the second level of protection. It automatically sets maximum thrust. When it is not possible to recover a positive flight path angle using the pitch control an aural alert "SPEED SPEED SPEED" is repeated every 5 seconds:
The low energy alert is triggered when the speed is close to V alpha-prot, but it can be triggered closer to VLS, in the case of:
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The MAX TURB speed-Mach depends on:
When the speed goes below ______, the speedbrakes retract automatically.
The windshear alert consists of:
It flashes for 9 s, then remains steady, as long as the windshear is detected.
Optimized descent path - The descent path computation does take into account the position of the speed brakes.
During the DES flight phase, the FMS updates the descent path, if the flight crew changes the flight plan or any approach data (approach wind, VAPP, or landing configuration). The descent path computation does NOT take into account the position of the speed brakes.
The load factor is automatically limited to:
Optimized descent path - The FMS computes the descent path in order to minimize the fuel consumption, and to reach VAPP at:
In normal law, the aircraft is protected against overspeed but whatever the active flight control law, the OVERSPEED warning is triggered:
Whatever the active flight control law, the OVERSPEED warning is triggered 4 kt above VMO, or M 0.006 above MMO
VS1G is computed by the PRIMs and it is the reference speed used for the computation of VLS, S, F, VREF.
When the AP is engaged, the low energy alert is available whatever the aircraft altitude and the position of the slats-flaps.
The load factor demand is limited to:
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Green dot speed is displayed on the airspeed scale of the PFD:
When the bank angle is excessive (risk of engine or wing tip strike) close to the ground, an aural "BANK BANK" (synthetic voice) is triggered.
During landing, if the pitch attitude is excessive, when close to the ground, an aural alert "PITCH PITCH" is triggered is above 10.5 degrees. The pitch attitude aural alert is available:
Alpha-floor is available:
What is VS1G?
When the AP is engaged, the low energy alert is available whatever the aircraft altitude and the position of the slats/flaps. In manual flight, the low energy alert is available:
The maximum achievable bank angle is 67 degrees (60 degrees in high lift configurations).
If the takeoff is performed in CONF 2 or CONF 3, "F" appears:
The PRIMs compute Green dot speed. The FMS also computes the green dot speed. It is displayed on the T.O, APPR, and GA panels of the FMS PERF page. Green dot depends on:
If no climb speed limit and no climb speed constraint are defined in the flight plan, the managed speed-Mach target, from the acceleration altitude and to the TC, is the optimized ECON speed-Mach.
The optimized speed/Mach ECON, LRC, or RTA.
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The alpha-floor remains inhibited as long as the TCAS mode is engaged.
For a normal acceleration, the high speed protection activates when the speed is between:
VLS provides a margin:
VFE is the maximum speed with the slats or flaps extended. There is one VFE per configuration. The VFE for each slats/flaps configuration is also displayed on the speeds placard in the cockpit. The display of the VFE is based on:
Managed speed profile - From liftoff to the acceleration altitude, the managed speed target is:
The magenta triangle on the PFD airspeed scale indicates V2. However, the managed speed target is V2 + 10 kt.
VS1G depends on:
VREF is equal to the:
The angle of attack protection activates when the angle of attack exceeds alpha-max.
The angle of attack protection activates when the angle of attack exceeds alpha-prot. In any case, the angle of attack cannot exceed alpha-max.
VLS is the lowest selectable speed. It is computed by the FMS and is displayed in flight only. It appears:
When the speed is at or below VMO, the thrust reverts to manual thrust if the A/THR was not active before the activation of the high speed protection. The level of thrust is set in accordance with the position of the thrust levers.
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VD/MD is the design dive speed, which is the maximum structural speed:
The FMS displays the maximum turbulence penetration speed in the MAX TURB field on the CRZ panel of the FMS PERF page. The maximum turbulence speed is below VRA-MRA (the recommended turbulence penetration airspeed).
The maximum turbulence speed is above VRA/MRA.