What is hard deck?

A hard deck is a predetermined minimum altitude that a pilot must maintain during a flight operation. It is often used in military operations to ensure that aircraft stay above a safe altitude, which reduces the risk of collision with the ground or obstacles. The hard deck can vary depending on the mission, location, and aircraft type, and may be adjusted depending on weather conditions or other factors. Violating the hard deck can result in disciplinary action or even aircraft loss. Overall, the hard deck is an important safety measure that helps to prevent accidents and protect pilots and passengers.