High Angle-of-Attack Protection A330

A critical angle of attack where the aircraft activates a protection system.

The maximum safe angle of attack for the aircraft.

Automatic go-around thrust deployment when entering αPROT.

Returning from angle-of-attack protection involves pushing forward the sidestick to reduce the angle of attack.

Disconnecting go-around thrust after reaching a safe speed by using a thrust lever disconnect button.

A system that protects the aircraft from stall during dynamic maneuvers or gusts by maintaining the angle of attack at a safe level.

The angle of attack at which the high AOA protection activates. It's the protected limit.

The maximum angle of attack the aircraft can achieve with flight crew input in high AOA protection.

Speed at which high AOA protection activates, depends on config, weight and load factor.

Maximum speed at which the flight crew can achieve αMAX in the High AOA protection without losing control.

The system that calculates the protection speeds and the activation logic for alpha floor.

High AOA protection takes precedence over other protections. Protects from stall.

An angle of attack condition, computed by PRIM, that activates at a predefined angle

These three values are all related to the aircraft's angle of attack (AOA) and are calculated based on the current configuration, weight, and load factor. They work together to prevent stalls and ensure safe flight.

These values are constantly adjusted based on factors like aircraft configuration (flaps, landing gear), weight, and how much force is being applied to the aircraft (load factor). These factors individually or together can change how the aircraft flies, so the protection system needs to change too.

The PRIM system computes the speeds at which high Angle of Attack (AOA) protection activates (Vα PROT and Vα MAX) and the Alpha Floor angle.

Vα PROT is the speed at which the High AOA protection system activates. It varies based on aircraft configuration, weight, and load factor.

Vα MAX is the maximum speed the pilot can achieve while utilizing the High AOA protection system without losing control.

Alpha Floor is a predefined angle of attack that, when reached, triggers automatic go-around thrust deployment. It is calculated by PRIM.

This system prevents the aircraft from stalling during dynamic maneuvers or gusts. It ensures a safe angle of attack by maintaining the angle at a specific level.

The angle of attack (α) at which the high AOA protection system (αPROT) activates. It's a critical angle of attack beyond which the aircraft activates its protection system to prevent a stall.

When exiting αPROT, the pilot needs to push the sidestick forward to reduce the angle of attack and prevent a stall. This is because αPROT limits the angle of attack, and when leaving the protected zone, the aircraft could exceed the safe limit.

The alpha (α) for αPROT (high AOA protection) decreases with increasing Mach number (speed). This means that the aircraft is more likely to activate its protection system at higher speeds.

In certain situations, the aircraft can be flown with the sidestick fee (a slight forward force on the sidestick). This allows the aircraft to climb while maintaining the angle of attack within the αPROT protection bounds.

When leaving a turn after entering αPROT, the aircraft may climb with the sidestick fee due to the reduced αPROT. The reduced αPROT allows for a more gradual return to normal flight while staying within the protection system.

The aircraft exits angle-of-attack protection when the sidestick is pushed forward, reducing the angle of attack. This happens when the angle of attack is less than the protected limit (αPROT).

This system prevents the aircraft from stalling during dynamic maneuvers or gusts. It ensures a safe angle of attack by maintaining the angle at a specific level.

High angle-of-attack protection (αPROT) activates when the angle of attack (α) reaches a specific limit. This limit is either a fixed value (αMAX) or a dynamic value (αPROT).

αPROT and αMAX are both angle of attack values. αPROT activates when the angle of attack reaches a certain limit. αMAX is a maximum angle of attack that is safe for the aircraft.