From April 1965 to early 1966 and beginning again in late 1967, the EC-121Ds also controlled a flight of MiGCAP fighters for unarmed support aircraft operating over the Tonkin Gulf. The EC-121Ds also served as an airborne communications relay center for strike aircraft to transmit mission results and position reports to Danang Air Control Center; directed operations of fighter escorts, MiGCAPs, Lockheed C-130 Hercules flare ships and A-26 strike aircraft along the North Vietnamese-Laotian border; provided radar and navigational assistance for Combat Search and Rescue missions; and assisted fighters in finding tankers for emergency refuelling.