Private Pilot Flight Training and Instruction Flight Training Article Library | Back To 4VFR.COM Warning Areas Same as Restricted area but over international waters beyond 3 mile- limit of our borders. Contains hazards related to cannon, machine guns, and bombs. Clearance/flight plan required by U. S. aircraft. Warning areas cannot be designated by the FAA as restricted areas because they are over international waters. Warning areas are regulated by the FAA from 3 to 12 miles but not regulated by the FAA beyond 12 nm. Written by Gene Whitt Flight Training Article Library | Back To 4VFR.COM