The ships were lightly built, and the main difference from Hiryū was that the carriers' island was placed on the starboard side of the ships. The carriers were capable of carrying 63 aircraft in two hangars, and were fitted with two elevators. The Unryū class carried a smaller quantity of aviation fuel as Hiryū with fuel tanks protected by concrete. The ships were fitted with the same propulsion system used in the aircraft carrier Sōryū to reach 34 knots (63 km/h) | The ships were lightly built, and the main difference from Hiryū was that the carriers' island was placed on the starboard side of the ships. The carriers were capable of carrying 63 aircraft in two hangars, and were fitted with two elevators. The Unryū class carried a smaller quantity of aviation fuel as Hiryū with fuel tanks protected by concrete. The ships were fitted with the same propulsion system used in the aircraft carrier Sōryū to reach 34 knots (63 km/h) |