On 6 June, USS "Yorktown" left Majuro with TF 58 and set a course for the Mariana Islands. After five days steaming, she reached the launch point and began launching CVG-1 planes for the preliminary softening up of targets in preparation for the invasion of Saipan. CVG-1 aircrews concentrated primarily upon airfields located on Guam. Those raids continued until 13 June, when "Yorktown", with two of the task groups of TF 58, steamed north to hit targets in the Bonin Islands. That movement resulted in a one-day raid on 16 June before the two task groups headed back to the Marianas to join in the Battle of the Philippine Sea. TF 58 reunited on 18 June and began a short wait for the approaching Japanese Fleet and its aircraft.