What is the maximum airspeed for windshield wiper operation?

The maximum airspeed for windshield wiper operation is 250 KIAS. This limit is set because operating the windshield wipers at speeds higher than this can lead to damage or failure of the wiper system. At elevated speeds, the aerodynamic forces and the wind pressure can exceed the design capabilities of the wipers, increasing the risk of malfunction or even being dislodged from their mounts. Therefore, the 250 KIAS threshold is established to ensure safe operation and to maintain visibility under conditions where wipers might be necessary, such as during rain or other inclement weather.

In contrast, other options provided, such as specific altitudes or pressures, do not apply to the operation of windshield wipers and therefore are not relevant for determining the maximum airspeed at which they can function safely.