A 550 horsepower (410 kW) 16-cylinder Wolsey petrol engine powered the submarine on the surface, driving the submarine's single propeller shaft, while submerged propulsion was via a 150 horsepower (110 kW) electric motor, giving a speed of 11.5 knots (13.2 mph; 21.3 km/h) on the surface and 7 knots (8.1 mph; 13 km/h) dived.

[3] Immediately after commissioning she and her tender HMS Hazard travelled to Queenstown, (now Cobh) Ireland.

[4] An enquiry into the accident concluded that petrol fumes had been ignited by an electrical spark, with the second explosion caused by smouldering debris from the first event.

The Irish Naval Service donated a granite block with a brass plaque giving details of the A5 tragedy, and this was unveiled in March 2000.

LÉ Eithne of the Irish Naval Service and HMS Richmond of the Royal Navy visited Cobh for the occasion.