 During the Battle of the Coral Sea one month earlier , the Japanese light carrier Shōhō had been sunk and the fleet carrier Shōkaku had sustained three bomb hits , and was in drydock undergoing repairs . Although the carrier Zuikaku escaped the battle undamaged , she had lost almost half her air group , and was in port in Kure awaiting replacement planes and pilots . That there were none immediately available is attributable to the failure of the IJN crew training program , which already showed signs of being unable to replace losses . Instructors from the Yokosuka Air Corps were employed in an effort to make up the shortfall . 
