What instrument is primarily used for attitude indication in an aircraft?

The attitude indicator is the primary instrument used for attitude indication in an aircraft because it displays the aircraft's orientation relative to the horizon. This instrument provides crucial information on whether the wings are level or if the aircraft is climbing, descending, or banked left or right. The visual representation typically includes a symbolic aircraft against a backdrop of a moving horizon bar, allowing pilots to quickly assess their aircraft's direction and stability.

Understanding this instrument is vital for safe flight operations, especially in conditions where external visual references are limited, such as in poor visibility or in a cloud-covered environment. The attitude indicator helps pilots maintain controlled flight and execute proper maneuvers by providing immediate feedback about the aircraft's pitch and roll, which is fundamental to maintaining flight safety.