The convoy was subject to attack by German air, U-boat and surface forces and suffered the loss of five ships, plus one escort vessel. The ships of Convoy PQ 13 came under U-boat attack. That evening U-716 came close enough to fire on one of the escorts, while another was depth charged. As soon as the convoy came into range, the aircraft were to keep up a continuous attack until the convoy docked at Murmansk or Arkhangelsk.