Iran confirms deployment of Ghadir-class midget submarines in Strait of Hormuz to counter US Navy.

Iran has confirmed the deployment of domestically built Ghadir-class midget submarines inside the Strait of Hormuz as tensions with the U.S. Navy intensify, according to statements made on May 10, 2026, by Iranian Navy commander Rear Admiral Shahram Irani during a naval exercise honoring sailors lost aboard the frigate Dena. The move strengthens Tehran’s ability to threaten commercial shipping and naval forces in one of the world’s most critical maritime chokepoints by relying on hard-to-detect submarines optimized for shallow-water ambush operations and asymmetric sea denial tactics.

The Ghadir-class was designed specifically for confined Gulf waters where heavy shipping traffic, shallow depths, and difficult sonar conditions reduce anti-submarine warfare effectiveness, allowing the submarines to conduct seabed “bottom rest” concealment before launching short-range torpedo or missile attacks. Historical experience from World War II to the 2010 sinking of the South Korean corvette Cheonan has repeatedly shown that midget submarines operating in congested littoral waters can impose disproportionate operational and force protection costs on larger naval forces despite their limited size and endurance.

Related topic: Iranian Navy frigate IRIS Dena sinks near Sri Lanka after possible submarine attack

In the Strait of Hormuz, Iran’s small Ghadir-class submarines could hide near shipping lanes and launch sudden attacks, much like World War II midget submarines that exploited confined coastal waters to damage not only merchant ships but also battleships. (Picture source: Iranian MoD)

On May 10, 2026, Iran’s Army Navy commander Rear Admiral Shahram Irani confirmed that domestically produced light submarines are deployed in the Strait of Hormuz under heightened readiness conditions as tensions with the U.S. Navy continue to escalate around the strategic waterway. The announcement followed a naval maneuver dedicated to personnel lost aboard the frigate Dena, sunk on March 4, 2026, in the Indian Ocean off Sri Lanka during U.S. military operations against Iranian naval assets. During the exercise, several submarines surfaced in formation in the Strait before submerging again and returning to patrol positions.

Iranian naval command identified the boats as part of the “dolphins of the Persian Gulf” force, a designation used internally for small coastal submarines assigned to shallow-water anti-ship and denial missions. The deployment reflects Iran’s continuing focus on asymmetric maritime warfare inside the Strait of Hormuz, where shipping lanes narrow to less than 4 kilometers in each direction at some transit points, and average operating depths remain between 30 and 60 meters. The submarine force associated with that designation is centered on the Ghadir-class, a diesel-electric midget submarine family designed specifically for Persian Gulf operations, though Iranian references occasionally include the Nahang-class and Fateh-class coastal submarines.

The Ghadir-class entered operational service in 2007 after several years of development by the Marine Industries Organization and currently constitutes the largest segment of Iran’s operational submarine inventory. Each boat measures 29 meters in length, 2.75 meters in beam, and displaces 117 tons surfaced and 125 tons submerged. Crew size is seven personnel. Iranian reports indicate that between 14 and 20 Ghadir-class submarines remain operational, although some U.S. estimates previously stated that 11 midget submarines were lost by Iran during the 2026 conflict.

Iranian naval records identify Ghadir 955 as the fourteenth submarine completed domestically, while Ghadir 942 underwent major reconstruction and overhaul before re-entering service. The boats are assigned primarily to the Southern Fleet operating from Bandar Abbas and nearby naval facilities overlooking the Strait of Hormuz. The operational concept behind the Ghadir-class differs substantially from conventional attack submarines intended for blue-water patrols. The boats were designed for short-duration ambush missions in shallow, high-traffic waters where acoustic clutter complicates sonar detection.

Iranian naval planners adapted the class specifically for the environmental conditions of the Persian Gulf, where high salinity, suspended sediment, tidal shifts, and rapid thermal-layer changes degrade underwater detection performance. Iranian naval engineers cited earlier operational difficulties experienced by imported Kilo-class submarines during warm-season operations in Gulf waters as one factor driving development of a smaller indigenous design. The Ghadir-class can reportedly leave port and transition to operational status within 30 seconds, allowing rapid dispersal during periods of crisis.

Their small dimensions also allow navigation close to islands, oil terminals, and coastal shallows inaccessible to larger submarines operating in the same region. A central feature of the submarine’s operating profile is its ability to conduct “bottom rest” operations directly on the seabed. Iranian naval personnel stated that the submarines can shut down propulsion systems completely and remain stationary on muddy or sandy seabeds for extended periods while monitoring nearby maritime traffic. In the Persian Gulf environment, this tactic exploits a combination of shallow depth, sediment suspension, and dense civilian shipping traffic to reduce acoustic and magnetic detectability.

In narrow sections of the Strait of Hormuz, commercial and military traffic passes through predictable transit corridors, allowing stationary submarines to position themselves near anticipated shipping routes. Iranian naval commentary repeatedly emphasized that the boats are intended to wait motionless for prolonged periods before executing short-range torpedo attacks against passing vessels. This operating concept differs from continuous submerged patrol patterns commonly associated with larger attack submarines. The Ghadir-class carries two 533 mm torpedo tubes capable of launching heavyweight torpedoes and naval mines.

Iranian inventories and naval statements refer to compatibility with the Valfajr torpedo, Hoot supercavitating torpedo, and Jask-2 submarine-launched anti-ship missile. The submarines can also deploy Nasr-1 anti-ship missiles and conduct mine-laying operations in confined shipping lanes or harbor approaches. Payload limitations remain significant because of the submarine’s size, with most operational loadouts consisting of either two heavyweight torpedoes, combinations of torpedoes and mines, or limited anti-ship missile carriage. Iranian naval doctrine compensates for those restrictions through concentration of multiple submarines inside confined waters rather than relying on single-vessel engagements.

The boats are also configured for special operations support, including insertion of naval commandos and underwater combat divers through forward escape and deployment compartments. Iran invested heavily in reducing the acoustic profile of the Ghadir-class because survivability inside the Gulf depends more on concealment than speed or endurance. The submarines use diesel-electric propulsion systems with low-noise operating characteristics during submerged operations. Iranian naval production data indicates that the boats incorporate compact sonar systems, automatic depth-control systems, digital fire control architecture, and integrated navigation systems optimized for shallow-water maneuvering.

The hull design minimizes hydrodynamic noise generation during low-speed movement, while onboard systems reportedly include secure communications links connecting submarines with coastal command centers, naval aviation units, surface combatants, and missile batteries. Iranian naval modernization programs later replaced earlier analog systems with digital displays and electronic processing systems to reduce maintenance cycles and improve operational reliability. Crew survivability systems include onboard oxygen generation, air purification equipment, fire suppression systems, compressed-air systems, and emergency escape mechanisms.

Since 2005, Iranian naval exercises have repeatedly incorporated the Ghadir-class into reconnaissance and ambush scenarios involving U.S. naval formations operating in the Persian Gulf and Gulf of Oman. During the Ettehad-84 naval exercise, the submarines tested torpedo-launch procedures, submerged maneuvering, and coordinated operations with surface units. Iranian naval officers later claimed that Ghadir-class boats maneuvered undetected near U.S. carrier strike groups and surfaced at close range before withdrawing underwater. Iranian military personnel also referenced underwater reconnaissance missions conducted beneath anchored foreign warships operating in Gulf waters.

These accounts are consistent with Iran’s broader signaling strategy, emphasizing proximity operations and seabed concealment rather than long-range submarine patrols. The boats have additionally operated beyond the Strait of Hormuz into the Gulf of Oman and northern Indian Ocean during naval deployments involving support ships such as Deylam, Hendijan, Falakhon, and Khanjar. The strategic importance of the Ghadir-class increased after major losses suffered by Iran’s surface fleet during the 2026 conflict involving U.S. and Israeli strikes on Iranian naval infrastructure and combatants.

Iranian fleet records now list the frigates Dena, Alvand, Sabalan, Sahand, Jamaran, and Deylaman among vessels lost during the conflict, alongside the Fateh submarine, Taregh submarine, Makran forward base ship, multiple missile boats, and several Islamic Revolutionary Guard Corps Navy corvettes and fast attack craft. The loss of larger surface combatants increases the relative value of small submarines capable of surviving inside heavily monitored coastal waters. Unlike frigates or large auxiliary vessels, Ghadir-class boats present smaller radar, acoustic, and thermal signatures and can disperse across multiple small naval facilities and coastal anchorages.

Iran’s continued emphasis on midget submarines, therefore, reflects both environmental suitability and force-preservation considerations after substantial attrition within the conventional fleet structure during 2026 operations. Iran’s midget submarine development program originated during the late stages of the Iran-Iraq War and expanded through cooperation with North Korean coastal submarine designs during the late 1980s and early 1990s. Iranian naval procurement records indicate that several imported North Korean submarines entered service before Tehran shifted toward indigenous serial production during the early 2000s.

Construction of the Ghadir-class involved expertise from multiple sectors, including hydrodynamics, metallurgy, electronics, oceanography, propulsion engineering, communications systems, and weapons integration. Iranian naval industry officials estimated production cost at $17 million to $18 million per submarine during the mid-2000s, allowing acquisition of multiple boats for the cost of a single conventional attack submarine purchased internationally. That procurement logic aligns with Iran’s broader naval doctrine, which prioritizes distributed coastal defense assets, survivability through dispersion, and high-volume asymmetric maritime capabilities concentrated around the Strait of Hormuz and the Persian Gulf littoral.

The combat history of midget submarines during World War II shows that these vessels rarely achieved strategic effects independently but repeatedly demonstrated tactical utility in shallow littoral waters, harbor approaches, and confined maritime chokepoints where geography degraded anti-submarine warfare effectiveness. Imperial Japan fielded the first large-scale wartime midget submarine force with the Type A Kō-hyōteki class developed in the late 1930s. Each displaced roughly 46 tons submerged, carried two 450 mm torpedoes, and operated with a two-man crew.

Five participated in the 7 December 1941 Pearl Harbor attack, but none returned. Postwar U.S. and Japanese assessments concluded their direct operational impact was limited relative to the carrier air strikes, although one torpedo likely struck the battleship USS West Virginia or USS Oklahoma. More significant results occurred on 31 May 1942 during the attack on Diego Suarez, Madagascar, where a Japanese midget submarine penetrated harbor defenses, heavily damaged the Revenge-class battleship HMS Ramillies, and sank the 6,993-ton tanker British Loyalty, demonstrating the effectiveness of small submarines in restricted coastal waters where larger submarines faced maneuver limitations.

Nazi Germany's experience evolved toward coastal interdiction after heavy Atlantic U-boat losses. Beginning in 1944, the Kriegsmarine expanded its Kleinkampfverbände program with several midget submarine types, including Biber, Molch, Neger, and Seehund. Early designs suffered severe operational losses because of unreliable propulsion systems, poor seaworthiness, and limited crew training. The electrically powered Molch conducted more than 100 Mediterranean sorties in late 1944 without sinking a confirmed Allied vessel. The later Seehund class proved substantially more effective.

Displacing approximately 17 tons surfaced and armed with two externally mounted G7e torpedoes, the two-man submarine conducted operations in the North Sea and English Channel between January and April 1945. German and British postwar records credited Seehund boats with sinking roughly 8 to 10 merchant ships totaling over 17,000 gross registered tons while losing about 35 submarines, many because of weather conditions rather than Allied action. British anti-submarine units reported persistent detection difficulties because of the vessel’s extremely small radar and acoustic signature, although the campaign produced no strategic effect given Germany’s collapsing military position by 1945.

British X-craft operations produced the most strategically consequential midget submarine attack of the war. The X-class displaced approximately 27 tons submerged, carried four-man crews, and transported large side-mounted explosive charges rather than torpedoes. During Operation Source on 22 September 1943, six X-craft targeted the German battleship Tirpitz anchored in Kaafjord, Norway. Two submarines penetrated anti-submarine nets and placed charges beneath the hull. The explosions caused severe structural damage, killed or wounded more than 100 German personnel, and rendered Tirpitz combat ineffective for roughly six months.

British naval assessments later concluded that the operation temporarily neutralized the principal German surface threat to Arctic convoys without requiring a major fleet engagement. Postwar naval analysis consistently concluded that midget submarines are most effective in shallow coastal waters, congested shipping lanes, and chokepoints where large anti-submarine vessels cannot fully exploit speed, sonar range, or maneuverability advantages. This assessment heavily influenced North Korean submarine development during the Cold War, particularly the Sang-O and Yono classes optimized for Yellow Sea and Korean littoral operations.

The most consequential modern example occurred on 26 March 2010, when the South Korean Pohang-class corvette ROKS Cheonan sank near Baengnyeong Island, resulting in the loss of 46 sailors. The multinational Joint Civilian-Military Investigation Group concluded that the ship had been struck by a North Korean CHT-02D torpedo likely launched from a Yono-class midget submarine, citing recovered torpedo fragments, explosive residue, and acoustic evidence.

Although Russian analysts questioned parts of the investigation, no alternative explanation achieved broad international acceptance. The incident reinforced long-standing Western and Asian naval assessments that small diesel-electric midget submarines, like Iran's Ghadir-class, operating in cluttered littoral environments, like the Strait of Hormuz, remain difficult to detect and can impose disproportionate operational and force protection costs despite limited payload, endurance, and survivability.

Written by Jérôme Brahy

Jérôme Brahy is a defense analyst and documentalist at Army Recognition. He specializes in naval modernization, aviation, drones, armored vehicles, and artillery, with a focus on strategic developments in the United States, China, Ukraine, Russia, Türkiye, and Belgium. His analyses go beyond the facts, providing context, identifying key actors, and explaining why defense news matters on a global scale.