That white dome atop the van, which is similar to the device that'll soon be mounted on JetBlue's fleet, maintains a constant connection by rotating instantly as the van moves -- if the vehicle's heading changes, the antenna array will turn, too, so it's always pointed directly at the sat in the sky.

ENGADGET: Visualized: JetBlue and ViaSat test Fly-Fi in-flight WiFi... from the ground