First-time flyers fly in the belly-to-earth position, which requires the slowest airspeed of any position up to 220 km/h (136 mph). This means that even the slowest wind tunnels are able to accommodate the main indoor skydiving market. Modern facilities operate at high speeds to support the needs of skydivers and pro-flyers, which enjoy having speeds of up to 300 km/h (186 mph).