What is a primary concern when landing on wet or contaminated runways?

When landing on wet or contaminated runways, the primary concern is decreased landing roll and reduced control. Wet or contaminated surfaces can significantly impact the braking ability of the aircraft, leading to longer distances required to come to a complete stop. Additionally, the reduced friction between the tires and the runway can make it more difficult for pilots to maintain directional control during the landing phase, particularly if they encounter hydroplaning. This condition occurs when a layer of water prevents the tires from making direct contact with the runway, greatly compromising the aircraft's ability to slow down effectively and maintain stability.

Decreased traction not only extends the landing roll but also poses challenges in handling, especially during crosswinds or when executing a go-around procedure. Hence, pilots must be acutely aware of these factors and adjust their landing techniques accordingly, often approaching with a higher airspeed and maintaining a precise control of descent to mitigate the risks associated with wet or contaminated runways.