What feature indicates a caution range on the airspeed indicator?

The yellow arc on an airspeed indicator represents the caution range, which serves a specific purpose during flight operations. This range indicates airspeeds that require careful attention; flying within this range can lead to potential challenges, such as increased stall risk or decreased control effectiveness in a given aircraft. Pilots are cautioned to be vigilant when flying in this range to avoid exceeding operational limitations or encountering undesirable flight conditions.

In contrast, the green arc indicates the normal operating range, where the aircraft is performing safely and effectively. The white arc indicates the flap operating range, showing speeds at which flaps may be safely deployed. The red radial line typically marks the maximum airspeed limit beyond which the aircraft should not be flown, as it represents a critical safety threshold. Understanding these ranges helps pilots make informed decisions regarding airspeed management and overall flight safety.