Which protection is NOT a normal law protection?

Alpha lock is a protection feature that is unique to the envelope protection system of the A320, specifically designed to prevent stalling by limiting the aircraft's angle of attack in certain conditions. It activates in a situation where the aircraft is at risk of exceeding its critical angle of attack, essentially activating when a pilot might inadvertently push the aircraft into a stall condition.

In contrast, the other options—load factor limitation, high angle of attack protection, and bank angle protection—are indeed part of the normal law protections that help govern flight parameters under standard operating conditions. Normal law provides several protections to ensure safety, including limiting the load factor, preventing excessive angles of attack, and maintaining a safe bank angle during maneuvers. These protections are intended to assist the pilot in maintaining control of the aircraft and to prevent it from entering unfavorable flight conditions.

Thus, identifying alpha lock as the feature not included in normal law protections highlights the understanding of different operational modes of flight control systems on the A320.