Iran's Big Little Fleet

Iran announced that they have put another three of their Ghadir class submarines into service. This is another example of Iranian resourcefulness in the face of embargoes. Since 1996, when Russia agreed to stop selling them submarines, Iran has been working on their own designs. After ten years of trial and error they produced the 115 ton Ghadir (Qadir) class vessels in 2005. Iran claims to have a fleet of 17 of these small diesel electric subs in their arsenal and no less than four have been shown together and photographed. The Iranians are not releasing specification sheets to anyone but Ghadirs look very similar to the Italian made Cosmos SX-506B, submarines that Columbia has operated since the 1980s. The 100-ton SX-506Bs are only large enough to carry commandos and mines. However released news footage shows what looks like to be two torpedo tubes on the Iranian Ghadirs. The Iranians claim that the Ghadirs carry torpedoes.
It should be remembered that Cosmos exported a number of larger vessels to Pakistan in the 1990s. Dubbed the SX-756 they may have been the design basis for the Ghadir. It should also be acknowledged that the North Korean Sang-O class submarine closely approximates the Ghadir type. In 2007 North Korea gave Iran, outright, four of its Yugo-type midget submarines. These Yugos were well worn 90-ton 21 meter (65 foot) craft but Iran accepted them all the same.
A one-off design, dubbed the Nahang, was produced in 2006. At about 500-tons it is the same size as and closely resembled the old German Type-206 class. The Type 206s were produced in the 1960s for operations in the confined shallows of the Baltic. Denmark, Norway, Germany, and now Indonesia used variants for forty years. The Type 206’s size enabled it to carry eight torpedo tubes with no reloads. The Iranian version does not seem to be a success and little has been seen of this craft.
Under construction is what will be the third indigenous Iranian design. Laid down in 2008, the Qaaem will be a 1,000 ton craft and historically should be large enough to handle a full set of torpedo tubes along with a reload. They could be the possible replacement for Iran’s Kilos. The Kilo platform has a lifespan of 30-years and they are more than halfway there. But Iran has a mixed record when it comes to warship construction and the Ghadir boats are reported to be troublesome to use and not safe. The Iranians are enthusiastic about having more subs, but developing that capability is very expensive and time consuming.
Iran took the big leap in the early 1990s when they acquired three Kilo 877/636 type diesel electric submarines from Russia. The 2300 ton Kilos are long range subs capable of operating throughout the Indian Ocean (from South Africa to Australia). The Kilos have six 533mm (21 inch) torpedo tubes and 18 torpedoes (including one or more Shkval rocket torpedo) or 24 mines. Very similar to the world-standard diesel submarine, the 1800-ton German Type 209, the Kilo is a formidable foe and can stay at sea for up to 45 days, which makes it capable of long range patrols, like a recent one in the Red Sea. That, in fact, was the farthest any of the Iranian Kilos have ever travelled from home. The Ghadirs are strictly for coastal work or missions out into the Persian Gulf. 

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