A USAF E-3 Sentry. An airborne warning and control system aircraft that provides all-weather surveillance, command, control, and communications needed by commanders of US and NATO. Photo: USAF/File photo.

A USAF E-3 Sentry. An airborne warning and control system aircraft that provides all-weather surveillance, command, control, and communications needed by commanders of US and NATO. Photo: USAF/File photo.