The surfacing of the Pipinos submarine was a "missile type," and at some point it reached an angle of 52 degrees, the militaire.gr portal reported, adding that the incident led to minor injuries to several crew members.
Experts are investigating the incident, but the possibility of a human error is excluded, according to the portal. The Hellenic Navy General Staff has not provided any information on the incident.
The Pipinos submarine belongs to the U214 class, and was launched in October 2014.
Four submarines of this type were built by the shipbuilding company ThyssenKrupp Marine Systems. Their construction was delayed and was accompanied by a number of scandals. The first submarine of this series, the Papanikolis, was infamous for excessive rolling during surfacing due to shipbuilding errors.