[1] For surface running, the boats were powered by a single 16-cylinder 600-brake-horsepower (447 kW) Vickers petrol engine that drove one propeller shaft.

On the surface, the C class had a range of 910 nautical miles (1,690 km; 1,050 mi) at 12 knots (22 km/h; 14 mph).

They could carry a pair of reload torpedoes, but generally did not as they would have to remove an equal weight of fuel in compensation.

The boat was sunk in a collision with the collier Eddystone in the North Sea south of Cromer, Norfolk on 14 July 1909.

[4] Attempts were made to salvage the stricken submarine but they were abandoned in September 1909, after only a single body had been recovered.