The maximum achievable bank angle is plus or minus:
? 67 °, within the Normal Flight envelope (2.5 g level flight)
? 45 °, in high AOA protection or high speed protection.
HIGH SPEED PROTECTION
When flying beyond maximum design speeds VD/MD (which are greater that VMO/MMO), there is an increased potential for aircraft control difficulties and structural concerns, due to high air loads. Therefore, the margin between VMO/MMO and VD/MD must be such that any possible overshoot of the normal flight envelope should not cause any major difficulty.
High speed protection adds a positive nose-up G demand to a sidestick order, in order to protect the aircraft, in the event of a dive or vertical upset. As a result, this enables a reduction in the margin between VMO/MMO and VD/MD.
Therefore, in a dive situation:
? If there is no sidestick input on the sidestick, 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 without reaching VD/MD. At approximately VMO +16 / MMO +0.04, the pitch nose-down authority smoothly reduces to zero (which does not mean that the aircraft stabilizes at that speed).
OPERATIONAL PHILOSOPHY
FLIGHT CONTROLS
airbus HIGH SPEED PROTECTION
The PF, therefore, has full authority to perform a high speed/steep dive escape maneuver, when required, via a reflex action on the sidestick. In addition, the bank angle limit is reduced from 67 to 45 °, which minimizes the risk of a spiral dive.
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