Key Point: Though the new Iranian boats may remain far from the cutting edge of submarine design, they could still prove dangerous adversaries in the confined and shallow waters of the Persian Gulf.
The Iranian military has long planned for a defensive naval war in the Persian Gulf, in which it would leverage its large fleet of fast attack boats toting antiship missiles to launch swarming hit-and-run attacks on adversaries in along Persian Gulf, with the ultimate goal of shutting down passage through the Straits of Hormuz.
Supporting this naval guerilla-warfare strategy are twenty-one indigenously produced Ghadir-class mini submarines, derived from the North Korean Yono class. The 120-ton vessels can poke around at eleven knots (thirteen miles per hour) and each carry two 533-millimeter torpedoes. All in all, shallow littoral waters are very favorable for mini-submarine operations, with interference from rocky shallows and loud surf reducing sonar detection ranges and giving mini submarines abundant opportunities to hide and wait in ambush. On the high end of the capability spectrum, Iran operates three much larger and more capable Kilo-class diesel-electric submarines purchased from Russia in the 1990s. These can comfortably hunt in the waters of the Indian Ocean.
Four years ago, Iran also launched its own domestically built Fateh-class submarine. The homemade vessel may lack modern features such as antiship missiles or quiet Air Independent Propulsion system, but it does seem to be the genuine article—not something one should take for granted with reports of new Iranian weapons.
Why would Iran invest considerable sums in building its own submarines instead of shelling out for off-the-shelf hardware in Russia or China?