A runway that is grooved or has a porous friction overlay is considered what when wet?

A runway that is grooved or has a porous friction overlay is considered "dry" when wet due to the specific engineering and design features of these surface treatments. Grooving and porous overlays are intended to enhance drainage and improve traction during wet conditions. The grooves create channels that allow water to flow away from the contact surface, reducing the amount of water that remains on the runway.

This design helps to maintain better tire-to-runway contact, which can decrease the likelihood of hydroplaning. Therefore, even if the runway is wet, the effective drainage means it can still provide a sufficiently safe and reliable surface for aircraft operations, effectively categorizing it as a "dry" condition rather than contaminated or unsafe.