On the ERJ 175, which component must be actuated to release the door from its locked position?

The gust lock is a crucial component for the operation of the ERJ 175's door system. Its primary function is to secure the aircraft’s doors in a closed and locked position, ensuring that they remain sealed during flight and are not inadvertently opened under high wind conditions or adverse situations.

Actuating the gust lock releases the door from its locked position, allowing the main handle to be used to open the door safely. This sequence is designed to prevent accidental opening of the door, which could lead to dangerous situations both on the ground and in-flight. Understanding the role of the gust lock is essential for ensuring the safety and proper operation of the aircraft’s doors during ground operations.

In this context, the other components listed have distinct roles. The emergency handle is typically used for manual operations in emergencies, the main handle is used to physically open the door once it is unlocked, and the caution strap is primarily there to ensure that crew members do not inadvertently put themselves in danger when the door is operated. The successful release of the door relies specifically on the proper actuation of the gust lock mechanism first.