What does the green arc on the AOA gauge indicate?

The green arc on the Angle of Attack (AOA) gauge indicates the normal approach speed, often referred to as the optimum angle of attack or "on-speed." This range is crucial for pilots to maintain during landings and approach since it represents the angle where the aircraft is most efficient and provides the best lift-to-drag ratio. Flying within this green arc ensures that the aircraft is in a safe zone of operation, optimizing performance while reducing the risk of stalling.

Maintaining the proper angle of attack as indicated by the AOA gauge is essential for safe operations, particularly during critical phases such as approach and landing. In other contexts, the AOA gauge provides information critical to understanding the proximity to stall conditions, but specifically, the green arc clearly delineates the safe and optimal operational range for approach.