sentences:  A Night Hawk helicopter from D Troop, 1st Squadron, 1st Cavalry Regiment (accompanied by a chase ship intended to drop flares and rescue the Night Hawk crew if there were problems) came on station and began engaging targets on the southeast slope of the hill.Forced to break station to refuel, the pilot (Captain Norman Hayes) learned that the additional gunships and medevac helicopters he'd requested when he came on station above Mary Ann had yet to be launched from the airstrip at Chu Lai.Communications failures left both brigade and division headquarters believing that Mary Ann was only being shelled by mortars, making the need for air support appear less critical.