The diesel engines of the V boats developed 450 bhp at 450 rev/min and were the first Vickers-built submarine engines to have steel cylinder jackets - previously these had been of cast iron. The battery consisted of 132 Exide cells - small for the size of boat considering that the A Class of less than half the displacement carried 120 cells. The designed submerged speed was still attained, although this at the expense of endurance.
Vickers claimed that the V Class could dive to 150 feet as against 100 feet in the conventional submarines of the period. Although the pressure hull sections were far from circular, this depth was possible because the strength of the hull was increased by the external framing between the inner and outer hulls.
The armament of the class was two 18-inch bow torpedo tubes,
