Alvand Class

The Alvand Class (also referred to as the Sa'am Class) is the official name of the Vosper Thornycroft Mk 5 1,100 ton displacement frigate in Iranian service. Each has a crew of between 125 and 146. These boats were refitted in Britain just before the 1979 revolution. There were four ships of this class in operation with the Iranian navy originally. Sahand was sunk by US Navy aircraft in April 1988, and Sabalan was crippled by a laser-guided bomb in the same action and spent two years in dock. Sabalan returned to service, but reportedly operated under some speed restrictions

The largest operational surface combatants remaining by the 1990s were these three British built frigates, commissioned in 1971-72 and refitted just before the Shah was overthrown. The Vosper Thornycroft Mk 5 is a mid-1960s design equipped with weapons of that period: Sea Killer (an early surface-to-surface missile), 4.5" and 20mm guns, and a Limbo ASW mortar. Sea Killer was an obsolete system in the 1990s. In addition the Iranian navy appeared to have run out of missiles during that period as well, fitting 122mm rockets instead.

The Alvand Class boats have since been rearmed, as part of a larger push in the Iranian navy. These upgrades most notably included the replacement of the Sea Killer missile system with the more capable C-802 cruise missile system found on a variety of Iranian vessels. Other improvements included the addition of torpedo tubes and a manned 35mm cannon turret in addition to the existing 20mm cannons.

They have a PLESSEY AWS-1 radar, a British-made manufacture in 1953, locally modernized; sonar TYPE 174-Britannic, appeared in 1951, active-passive, modernized by the Iranians; two fire control systems, type RTN-10X and radio-electronic warfare type, RDL-2AC; 4 missile craft manufactured by the Chinese C-802 or its local variant, called NOOR (depending on the variant, the maximum action range is between 30-200 km NOOR-1 -30 km / QADER -200 km); a BRK cannon, MARK-8 / DP-114 mm / 55 caliber (appeared in years * 70, having a fire rate of 20-90 projectiles / minute), but possibly it has been replaced with one of Soviet / Chinese fabrication; a 35 mm double AA cannon (possible local version of GDF OERLIKON); 4 20 mm guns; 2 machine guns 12.7 mm, local products after the Soviet DSHK; 2 triple torpedo launchers of 324 mm, possibly the local SKHVAL variant; two 81 mm cubes; an anti-submarine grenade launcher type LIMBO (A / S MK-10, British manufactured in the 1960s, possibly modernized or locally copied, about 35 tons of weight, launching 30mm reactive missiles, 94kg weight with a proximity / time warhead, a maximum action range of 366-914 m.

Each ship has a probable reserve of 51 projectiles, which would reach a maximum of 17 saves, being served by the Type 174 sonar); two machine guns of 0.5 mm, of local manufacture; an anti-submarine grenade launcher type LIMBO (A / S MK-10, British manufactured in the 1960s, possibly modernized or locally copied, about 35 tons of weight, launching 30mm reactive missiles, 94kg weight with a proximity / time warhead, a maximum action range of 366-914 m. Each ship has a probable reserve of 51 projectiles, which would reach a maximum of 17 saves, being served by the Type 174 sonar); two machine guns of 0.5 mm, of local manufacture; an anti-submarine grenade launcher type LIMBO (A / S MK-10, British manufactured in the 1960s, possibly modernized or locally copied, about 35 tons of weight, launching 30mm reactive missiles, 94kg weight with a proximity / time warhead, a maximum action range of 366-914 m. Each ship has a probable reserve of 51 projectiles, which would reach a maximum of 17 saves, being served by the Type 174 sonar); two machine guns of 0.5 mm, of local manufacture; being served by Type 174 sonar); two machine guns of 0.5 mm, of local manufacture; being served by Type 174 sonar); two machine guns of 0.5 mm, of local manufacture.

During the tanker war, Iran began using Sea Killer missiles fired from their four Saam-class frigates, which caused greater damage and casualties. In particular, the frigate Sabalan, under the command of Abdollah Manavi (also known as “Captain Nasty”) became notorious for deliberately firing into the crews’ quarters of neutral ships; in several instances, this resulted in high numbers of deaths.

At sea in the Gulf, U.S. Navy commanders had been given more liberal rules of engagement (ROE) to interfere in continuing Iranian attacks against neutral ships. Although U.S. Navy ships were still not allowed to defend foreign-flag ships, the new ROE permitted U.S. Navy ships to operate in proximity to neutral ships in order to deter an attack, or to aggressively maneuver and dog Iranian warships to give them something to worry about besides attacking other ships. The result was a number of instances of dangerous maneuvers and near-collisions between U.S. and Iranian warships.

In particular, the frigate USS Samuel B. Roberts (FFG-58) essentially harassed the notorious Iranian frigate Sabalan, breaking up several potential attacks. Given Sabalan’s track-record of high-casualty attacks, Samuel B. Roberts’s actions, under the command of Commander Paul X. Rinn, no doubt saved the lives of neutral seamen. In a couple of cases, Roberts and Sabalan mixed it up like two fighter pilots maneuvering to gain positional advantage, with the Roberts gaining the upper hand in each.

On 14 April 1988, watchstanders aboard USS Samuel B. Roberts (FFG 58) sighted three mines floating approximately half of a mile from the ship. Twenty minutes after the first sighting, as Samuel B. Roberts was backing clear of the minefield, she struck a submerged mine. The explosive device tore a 21-foot hole in the hull, causing extensive fires and flooding. Ten Sailors were injured in the attack. Only the heroic efforts of the ship’s crew, working feverishly for seven straight hours, saved the vessel from sinking. Four days later, forces of the Joint Task Force Middle East (JTFME) executed the American response to the attack: Operation Praying Mantis. The operation called for the destruction of two oil platforms being used by Iran to coordinate attacks on merchant shipping.

Operation Praying Mantis was the largest of five major U.S. Navy surface actions since World War II. It was the first, and so far only, time the U.S. Navy has exchanged surface-to-surface missile fire with an enemy, and it resulted in the largest warship sunk by the U.S. Navy since World War II. On 18 April, the coalition air and surface units not only destroyed the oil rigs but also various Iranian units attempting to counter-attack U.S. forces. By the end of the battle, U.S. air and surface units had sunk or severely damaged half of Iran’s operational fleet.

The primary tactical objective of the operation was to sink the Iranian frigate Sabalan. The larger objective was to inflict enough pain on Iran to deter them from laying any more minefields in the Arabian Gulf. A laser-guided bomb dropped from a Navy A-6 Intruder disabled frigate Sabalan (F 73), and Standard missiles launched from the cruiser Wainwright (CG 28) and frigates Bagley (FF 1069) and Simpson (FFG 56) destroyed the 147-foot missile patrol boat Joshan (P 225).

The Iranians did not get the de-escalation order, and at 1230 the Saam-class frigate Sahand (sister ship to Sabalan) departed Bandar Abbas, under the command of Captain Shahrokhfar. Although not as notorious as Captain “Nasty” Manavir, Shahrokhfar had a reputation as an aggressive skipper. Fighting continued when the Iranian frigate Sahand departed Bandar Abbas and challenged elements of an American surface group. Two VA-95 A-6E’s flying SUCAP for USS Joseph Strauss (DDG-16) spotted Sahand. The lead A-6 (piloted by future Rear Admiral Bud Langston) made an identification pass and was fired on by a hand-held SAM from Sahand. The Intruders replied with launches of two Harpoons and four laser-guided Skipper bombs. Langston fired a Harpoon at the vessel, and Joseph Strauss and the other A-6 followed suit; all three Harpoon’s probably hit. The A-6s attacked again with laser-guided Skipper missiles and bombs as other Enterprise aircraft rolled in with yet more ordnance. The weapons delivered against Sahand were successful. The damage to Sahand was severe, and she was soon burning stem-to-stern with fires out of control before a massive explosion in one of her magazines sank her, with a loss of at least 45 of her crew.

The loss of Sahand, one of Iran's most modern ships. was not enough to stop the suicidal sorties of the Iranian navy. A sister ship, Sabalan, departed her port for operations in the Gulf. The Iranians were still not sufficiently chastised, and at 1630 Sabalan finally departed Bandar Abbas. Although quickly located, there was only one U.S. aircraft nearby that had ordnance (after the field day on Sahand earlier). An A-6, flown by Lieutenant Commander James Engler (who had earlier sunk a Boghammer), conducted an identification pass and was fired on by an SA-7 hand-held surface-to-air missile from Sabalan. In accordance with the ROE, Engler (and his bombardier-navigator) responded by planting a Mk 82 500LB laser-guided bomb down Sabalan’s stack. (Engler would receive a Distinguished Flying Cross for his actions this day). The single hit crippled the ship, leaving her dead in the water and burning, with Captain Nasty immediately on the air pleading for help.

Unfortunately, the time it would take for other Enterprise Air Wing 11 aircraft to arrive and attack would seriously stretch the bounds of what could be considered permissible “self-defense” under the ROE. At this point, Secretary of Defense Carlucci approved CJCS Admiral Crowe’s recommendation to cease any further hostile action. Sabalan was towed back into Bandar Abbas and eventually repaired and returned to service. Captain Nasty would eventually achieve the rank of vice admiral. VA-95's aircraft, as ordered, did not continue the attack. This action ended the retaliatory strikes against Iran that began as a result of Iranian mining in international waters.

In further combat A-6s sank one Boghammer high-speed patrol boat and neutralized four more of these Swedish-made speedboats. One Marine AH-1T Sea Cobra crashed from undetermined causes, resulting in the loss of two air crew. Operation Praying Mantis proved a milestone in naval history. For the first time since World War II, U.S. naval forces and supporting aircraft fought a major surface action against a determined enemy.

It was a devastating loss for the IRIN and Iran as a whole. The battle clearly illuminated the IRIN’s deficiencies in conducting conventional warfare at sea against a capable opponent. The IranIraq War, including the Tanker War, would end only a few months following Operation Praying Mantis, but the engagement would leave an impression on Iran’s military leaders and shaped Iran’s naval forces in the decades that followed.

Combat Fleets 16th Edition noted that "Vickers Mk 8 automatic guns replaced the originally fitted semi- automatic Mk 6 during refits in the 1970s. Twin 23-mm 87-cal. ZU-23-2 Soviet AA mounts replaced the original Sea Cat SAM launcher and were in turn later replaced by single 20-mm mounts. The original quintuple-mount, trainable Sea Killer antiship missile system aft was replaced by fixed racks for Chinese-supplied C-802 missiles during 1996ñ98, and the associated target detection and tracking radar (which can also operate in the passive mode) has been stepped on a new lattice mast integrated into the forward edge of the original pylon mainmast. Around 2001 two sets of triple ASW torpedo tubes were added aft aboard Alvand, in place of the Limbo ASW mortar; the origin of the tubes and the type of torpedoes they may carry are unknown."

Speaking on Friday 27 September 2019, Deputy Coordinator of the Iranian Army Rear Admiral Habibollah Sayyari said that production of three new destroyers including Dena, Shiraz, and Taftan, is currently underway in the Ministry of Defense's Maritime Industry Department. The senior Army officials added that the Islamic Republic of Iran has made huge achievements meeting its military needs, saying that “today, the production lines of advanced military weapons such as missiles, fighter jets, warships, submarines, and tanks exist in the Islamic Republic of Iran.” He noted that the Iranian military experts are enhancing the level of domestically-made military weapons and equipment at the behest of commander in chief of Iranian armed forces, which is the Leader of the Islamic Revolution.

In a ceremony held through video conference, on 14 June 2021 Iranian home-grown destroyer “Dena”, as well as the “Shahin” minehunter, joined the Iranian naval fleet at the order of Iranian President Hassan Rouhani, in southern Port of Bandar Abbas. The ceremony was also attended by Iranian top military officials including Iranian Minister of Defense Brigadier General Amir Hatami, Iran’s Army Chief Commander Major General Abdolrahim Mousavi as well as Iran’s Navy Commander Rear Admiral Hossein Khanzadi.

Designed and built by Iranian experts at Iran’s Ministry of Defense and Armed Forces Logistics, Dena destroyer is a Mowj-class vessel equipped with advanced systems. Equipped with a variety of domestic equipment and defense systems, the Dena destroyer weighs more than 1300 tons and is able to sail long distances in the seas and oceans. Dena destroyer has the ability to search, detect, monitor, confront and, if necessary, destroy any aerial, land, and subsurface threats. Having a flight deck, from which helicopters take off and land, is one of the important capabilities of the Dena destroyer.