The designer told about the uniqueness of the Russian submarine "Piranha"

In particular, he noted that the submarine had a unique air-independent power plant, thanks to which the time spent under water would increase fourfold - up to 12 days.

“On the batteries alone, the boat can go no more than three days, and with the use of VNEU - up to 12 days at a speed of four knots of economic progress,” said Karavayev.

He clarified that during this time the submarine will need to periodically float to determine the location and reception of the radio session.