These callsigns are entered by the flight or ground crews. As such one sometimes . NAS Mayport FL AKSARBEN 55th Wing, Offutt AFB (Nebraska backwards) HYDRA CONTROL, TYNDALL AFB GCI OPERATIONS HYDRAMATIC CP. Летаю без крыла на Гидре в ГТА5!/Flying on Hydra without wing in GTA5! Velugy. Loading Unsubscribe from Velugy. The drone tech propulsion is called HYDRA, which Bell says stands for the unexpected stability of a circular wing in flight and certain control.