A13 was a member of the first British class of submarines, although slightly larger, faster and more heavily armed than the lead ship, HMS A1.
The submarine had a length of 105 feet 1 inch (32.0 m) overall, a beam of 12 feet 9 inches (3.9 m) and a mean draft of 10 feet 8 inches (3.3 m).
They displaced 190 long tons (190 t) on the surface and 206 long tons (209 t) submerged.
The A-class submarines had a crew of 2 officers and 11 ratings.

For surface running, A13 was powered by a single vertical, six-cylinder 500-brake-horsepower (373 kW) Hornsby-Akroyd oil engine that drove one propeller shaft.
When submerged the propeller was driven by a 150-horsepower (112 kW) electric motor.
They could reach 11 knots (20 km/h; 13 mph) on the surface and 6 knots (11 km/h; 6.9 mph) underwater.
The heavy oil engine was 3 long tons (3 t) heavier than the petrol engines used by the other boats in the class and an equal amount of fuel had to be removed, which reduced their range despite the heavy oil engine's more economical consumption.
On the surface, the boat had a range of about 400 nautical miles (740 km; 460 mi) at 10 knots (19 km/h; 12 mph); submerged the boat had a range of 30 nautical miles (56 km; 35 mi) at 5 knots (9.3 km/h; 5.8 mph).

The boats were armed with two 18-inch (45 cm) torpedo tubes in the bow.
They could carry a pair of reload torpedoes, but generally did not as doing so that they had to compensate for their weight by an equivalent weight of fuel.
A13 was a member of the first British class of submarines, although slightly larger, faster and more heavily armed than the lead ship, HMS A1. The submarine had a length of 105 feet 1 inch (32.0 m) overall, a beam of 12 feet 9 inches (3.9 m) and a mean draft of 10 feet 8 inches (3.3 m). They displaced 190 long tons (190 t) on the surface and 206 long tons (209 t) submerged. The A-class submarines had a crew of 2 officers and 11 ratings.
For surface running, A13 was powered by a single vertical, six-cylinder 500-brake-horsepower (373 kW) Hornsby-Akroyd oil engine that drove one propeller shaft. When submerged the propeller was driven by a 150-horsepower (112 kW) electric motor. They could reach 11 knots (20 km/h; 13 mph) on the surface and 6 knots (11 km/h; 6.9 mph) underwater. The heavy oil engine was 3 long tons (3 t) heavier than the petrol engines used by the other boats in the class and an equal amount of fuel had to be removed, which reduced their range despite the heavy oil engine's more economical consumption. On the surface, the boat had a range of about 400 nautical miles (740 km; 460 mi) at 10 knots (19 km/h; 12 mph); submerged the boat had a range of 30 nautical miles (56 km; 35 mi) at 5 knots (9.3 km/h; 5.8 mph).
The boats were armed with two 18-inch (45 cm) torpedo tubes in the bow. They could carry a pair of reload torpedoes, but generally did not as doing so that they had to compensate for their weight by an equivalent weight of fuel.
HMS A13