What is the first step in opening the flight deck window?

The first step in opening the flight deck window involves squeezing the lock release. This action is essential because it disengages the locking mechanism that secures the window, allowing it to be manipulated safely. Without first releasing the lock, attempting to rotate the handle or slide the window could result in damage to the mechanism or pose a safety risk, as the window is designed to remain closed during various phases of flight. Properly following this procedure ensures that crew members can operate the window while maintaining the integrity and safety of the flight deck environment.