Iran's Submarine Fleet Effectively Destroyed, Says Report

US Strike Deals Final Blow to Iranian Submarine Fleet

According to a report by The Maritime Executive, a U.S. Navy attack on the submarine maintenance facility at Bandar Abbas Naval Harbor on July 12 appears to have effectively ended Iran’s submarine warfare capability. The strike, carried out by three Saronic Corsair unmanned sea drones, destroyed the hoist mechanism used to lift submarines out of the water for repair, along with a Ghadir-class midget submarine that was in the hoist at the time.

A Fleet Already in Decline

The report notes that much of the damage to Iran’s submarine force had already occurred before this latest strike. At the outset of the conflict on February 28, two of Iran’s three Kilo-class submarines were in dry dock at Bandar Abbas undergoing deep refits that had been underway since 2021. The third, IRINS Tareq (S901), was reportedly the only semi-operational Kilo-class boat and was sunk at its home pier by the U.S. Navy in early March. Despite being intended as Iran’s premier undersea threat, the Kilo boats were described in the report as aging, unreliable, and noisy — liabilities rather than genuine assets.

That left the Ghadir-class fleet, roughly 20 small 125-ton midget submarines each crewed by seven sailors, as Iran’s remaining undersea capability. Though limited to short range and carrying only two torpedoes each, these boats have previously been observed launching Jask-2 anti-ship cruise missiles while semi-submerged — a tactic demonstrated during Exercise Velayat-97 in March 2017, when a missile canister was fired from a torpedo tube before its rocket motor ignited on the surface. The Jask-2, believed to be derived from the Chinese C-704 missile, has a range of about 20 nautical miles.

Removing the Repair Capability

While individually crude, the Ghadir boats posed an ambush risk precisely because of their small size and ability to sit undetected on the seabed awaiting targets. The July 12 strike removed Iran’s means of repairing any surviving Ghadir submarines by destroying the hoist and covered maintenance building at Bandar Abbas, which video of the attack showed had already sustained heavy damage. The report suggests it is possible that a Ghadir boat or trained submariners remain unaccounted for, but concludes that any meaningful regeneration of Iran’s submarine force would now require acquiring vessels from abroad.

What This Means for Commercial Shipping

For ship owners, managers, and charterers with vessels transiting the Strait of Hormuz, the practical takeaway is not that the underwater threat has vanished, but that it has shifted. Related reporting referenced in the same coverage notes continuing Iranian drone and missile strikes on tankers off Oman, including the Liberian-flagged Stolt Magnesium near an LNG terminal. With submarine ambush capability degraded, surface and aerial attacks appear to be the more immediate risk vector in the region.

This has direct operational implications. Vessels operating in or near the Strait of Hormuz should expect continued elevated war-risk premiums, tighter routing restrictions, and heightened scrutiny from charterers and insurers on vessel condition and crew readiness before entering the area. For operators, this is a reminder that pre-transit condition surveys, hull and machinery inspections, and thorough documentation of a vessel’s seaworthiness are not just regulatory formalities — they are commercially essential when transiting a contested chokepoint where attack, however unlikely for any single vessel, carries outsized consequences. Owners should also ensure that bunker and cargo documentation is airtight before entering high-risk zones, since any incident in the region can trigger extensive claims scrutiny where survey records become critical evidence.

As the conflict continues to reshape the naval balance around Hormuz, commercial operators would do well to treat independent, well-documented vessel inspections as a standard part of transit planning through the strait, not an afterthought.

Reviewed by Ibrahim Halil Ceylan, Marine Surveyor at Apeks Marine.