[citation needed] After leaving Yura Port for confirmation operation after regular inspection before 7:00 am on 8 October 2012, Sōryū began diving started at 8:47 am.

[2] On 2 September 2013, while the Sōryū was anchored at Kure base, an officer attempted to commit suicide in his quarters, using a pistol taken from the boat's weapons locker.

The parents of the disabled officer announced that they filed a lawsuit in the Yamaguchi District Court in January 2016, seeking damages of 30 million yen against the government.

[5] On 8 February 2021, Sōryū collided with commercial bulk carrier Ocean Artemis about 40 kilometres (22 nmi) southeast of Cape Ashizuri, when surfacing during a training exercise.

The submarine sustained damage to its communications equipment, conning tower, and diving planes, and three Japanese sailors were injured.