Iran Stealing Unmanned Vessels Shows US Navy’s Vulnerability?

The US Navy is investing in a series of artificial intelligence-powered autonomous watercraft designed to float on the ocean's surface — but recent confrontations with Iran have brought into question the usefulness of these unmanned vessels.

Iran has dispatched its navy ships to harass vehicles in the Arabian Gulf and surrounding waters. For example, on Aug. 30, an Iranian commercial ship operated by Tehran's Islamic Revolutionary Guard Corps Navy (IRGCN) tried to take in tow a US Navy Saildrone Explorer, a Maritime Autonomous Vehicle (MAV) designed to carry a variety of surveillance sensors. Reports from the region claim the US Navy's USS Thunderbolt patrol ship and an MH-60 Seahawk quickly engaged, convincing the Revolutionary Guard to release the unmanned vessel. Yet, the Tehran navy remained busy.

On Sept. 1, as the US Navy operated in the Red Sea, two of its Saildrone unmanned surface vessels (USV) were seized by Iranian naval forces. On this occasion, US Navy reporting revealed the Iranian frigate Jamaran lifted two American USVs out of the water, held them for 18 hours, and attempted to hide them under canvas sheets on the vessel's bow. Not fooled, two US destroyers in the vicinity stopped the Jamaran. A "Navy statement said the US Navy guided-missile destroyers USS Nitze and USS Delbert D. Black stayed near the Iranian warship, communicating with it … The Iranian warship released the drones in the morning on September 2," Reuters reported.

Iran Persists in Stealing USVs

The latest incident is the second time Iran has interfered with US Navy maritime operations in the Gulf region in less than a week by attempting to capture sea-borne drones. These two incidents raise an essential question: Are surface unmanned naval vessels more trouble than they are a necessary capability? The Tehran government attempting to steal US Fifth Fleet USVs is one thing. The better part of valor was for Iran to return the sea drones and call it a day. And it did. Nonetheless, despite the rapid engagement of the IRGCN by Fifth Fleet ships and subsequent surrender of US sea drones, in both cases, US Navy ships were taken off mission to retrieve USVs.

Had a similar situation occurred in the Taiwan Strait, with the Chinese People's Liberation Army Navy (PLAN) seizing unmanned naval vessels during hostilities or even peacetime, the likelihood of the PLAN giving them back would be less certain. Furthermore, sea drones being so vulnerable calls into question their value.

"Following the first incident earlier this week, Pentagon press secretary Brig. Gen. Patrick Ryder said he would not comment on how regularly these types of seizures might happen," US Naval Institute News reported. "So I'm not going to speculate on the hypothetical in terms of how often this could happen. Clearly, Fifth Fleet has it well in hand in terms of patrolling the waterway there and maintaining situational awareness in terms of their capabilities and assets in the region," Ryder said during the briefing. The fact that the IRGCN was able to steal the drone vessels in the first place calls into question Ryder's optimism.

US Navy Plans Fleet of USVs

The issue of the operational value of USVs is significant since the Department of the Navy has plans for acquiring a considerable number of the vessels over the next five years. According to an April 2022 General Accountability Office report:

"The Navy envisions using uncrewed maritime systems — robot ships and submersibles with artificial intelligence instead of sailors — to meet current and future threats at sea. The Navy estimates it will spend $4.3 billion to acquire 21 uncrewed vehicles over the next 5 years, but this estimate doesn't include the 'digital infrastructure' — e.g., data repositories and software — needed for AI."

The Navy's USV building program entails more than just small 23-foot-long Saildrone Explorer-type vessels and includes six different types of USVs. Larger autonomous surface vessels will be as long as 300 feet. Little is known about the self-defense capability of these vessels. However, operational concepts have the USVs augmenting deployed fleets. Policy regulating the use of self-defending autonomous naval vessels is not clear. The idea would be to engage enemy ships or land targets, not to turn on friendly ships. Additionally, the Navy must integrate the USV acquisitions into the larger Navy Department shipbuilding program.

Nevertheless, the experience in the Arabian Gulf and the Red Sea indicates how vulnerable autonomous vessels will be during hostile naval engagements. Consequently, some portion of the existing fleets will be tasked to protect the uncrewed vessels or count them as expendable. The US Navy's plan for USV investment is substantial. Taxpayers may be satisfied to buy MAVs to increase the Navy's combat capability, but not if these vehicles turn out to be liabilities.

The views expressed are those of the author and not of any other affiliation.