The deployment of actual combat capable B-57Bs from 8th and 13th Bomb Squadrons to Bien Hoa Air Base in August 1964 began with two aircraft lost and one damaged in collisions on arrival. An additional five aircraft were destroyed with another 15 damaged by a Viet Cong mortar attack in November of the same year. Low level sorties designated as training flights were conducted with the hope of it having a psychological effect. As a result, the first combat mission was only flown on 19 February 1965. The first excursion into North Vietnam took place on 2 March as part of Operation Rolling Thunder. The aircraft typically carried nine 500 lb (227 kg) bombs in the bomb bay and four 750 lb (340 kg) bombs under the wings. In April, Canberras began flying night intruder missions supported by USAF's Fairchild C-123 Provider or Lockheed C-130 Hercules flare ships and USN's EF-10B Skyknight electronic warfare aircraft.