Longest-range stealth mini-submarine

In 2013 a new stealthy mini-submarine, also known as a swimmer delivery vehicle, was produced by the British company James Fisher Defence. Called the Torpedo SEAL, the sub is stowed and carried in a NATO-standard 533-mm torpedo tube, and, once removed from this tube, is fully extended and ready for use. Capable of transporting two divers and equipment at about 4 knots over a range of 10 nautical miles, it is powered by a lithium polymer battery. It enables Special Forces personnel to undertake extended-range combat operations such as underwater reconnaissance, mine countermeasures, and delivery of explosives and counter-narcotics, along with enabling harbour-control measures.