main line of advance
головний напрямок наступу
головний напрямок наступу
main defense area (line) / main defensive position
hold advance / hold (up) advance
deployment line; line of deployment (LD); line of departure
main gear box / main rotor transmission
main-rotor hub / main-rotor head
main line of defense (resistance)
outline the main line of defense (of the enemy)