It soon became clear that the unarmed troop helicopters were vulnerable against ground fire from Viet Cong and North Vietnamese troops, particularly as they came down to drop their troops in a landing zone.
Pronto quedou claro que os helicópteros de tropas desarmadas eran vulnerables contra os disparos do Vietcong e das tropas norvietnamitas, particularmente cando baixaban para deixar ás súas tropas nunha zona de aterraxe.