Vann then ordered his pilot to make contact with the other L-19 that was leading the ten CH-21s with the first South Vietnamese reserve company from Tan Hiep. Vann relayed a message to the command pilot of the ten CH-21 helicopters, which were being escorted by a group of five recently deployed UH-1 Huey gunships, armed with 7.62mm machine guns and 2.75-inch rockets, and instructed him to land the reserve companies about from the western and southern tree lines that covered Ap Bac in order to minimize the effectiveness of the VC's .30 caliber machine guns. However, in the early phases of the war, command relationships between US military units were not well-established, and American aircrews had a tendency to disregard the instructions of advisors, especially Vann, who was regarded as domineering. Instead of following Vann's instructions, the command pilot decided to lead his helicopters over southern Ap Tan Thoi and along the creek to Ap Bac. The US pilots landed their helicopters west of Ap Bac, where they were hit multiple times by VC machine gun and small arms fire.