 The few aircraft on the Japanese flight decks at the time of the attack were either defensive fighters or , in the case of Sōryū , fighters being spotted to augment the Combat Air Patrol . Spotting his flight decks and launching aircraft would have required at least 30 to 45 minutes . Furthermore , by spotting and launching immediately , Nagumo would be committing some of his reserve to battle without proper anti @-@ ship armament ; he had just witnessed how easily unescorted American bombers had been shot down . Poor discipline caused many of the Japanese bombers to ditch their bombs and attempt to dogfight intercepting F4Fs . 
