30 November 2023

Could USS Eisenhower Now in Strait of Hormuz Stop Iranian Swarming Small Boats?

KRIS OSBORN, WARRIOR MAVEN

A powerful US Navy Carrier USS Dwight D. Eisenhower, cruiser and several destroyers joined a French destroyer transiting through the highly dangerous Strait of Hormuz bordering Iran, a narrow passageway connecting the Persian Gulf to the open ocean and Gulf of Oman.

The passageway is referred to as among the most critical “choke points” in the world, as massive amounts of commercial ship traffic travels through the waterway to deliver oil, supplies, food and other critical items traveling to and from key areas of the Middle East and beyond.

The Strait is only 90-miles wide in some places and as narrow at 35 miles at its most narrow point, so a US Navy aircraft carrier and its accompanying warships are well positioned to launch massive, impactful air and weapons attacks deep into parts of Iran should that be necessary. The show of US Navy power is likely a message of deterrence to Iran in response to Iranian-backed terrorist attacks on US personnel and facilities. The presence of such firepower is perhaps a reminder to Iran that indeed the US Navy operates with what is arguably an unparalleled ability to project destructive power.

The entire Persian Gulf spans roughly 210 miles across in many points, placing the Iranian coastline and other bordering areas easily within reach of carrier-launched fighter jets. Destroyers armed with Tomahawks, for instance, can also strike from hundreds of miles away from the Persian Gulf. Therefore, while the Persian Gulf’s Strait of Hormuz enhances and does not limit offensive strike capability for US warships, it does raise questions about ship-defenses and potential vulnerability to Iranian mines, shore-launched missiles and small boat attacks.

Of course littoral areas increase the risk of moored or freer floating sea mines intended to deny access to coastal areas, and certainly Iran operates a wide sphere of cruise missiles and ballistic missiles capable of targeting ships in the Persian Gulf, however the level of guidance accuracy, precision and ability to track and hit moving targets may be less certain. Nonetheless, concern over Iranian attacks are both quite significant and justified, given the geography of ocean passageways and known Iranian tactics. A report from US Central Command says Iran has interfered with or seized more than 20 vessels since 2021.

The largest Iranian threat, however, could perhaps best be described by possible attacks from small boats swarms designed to harass, intimidate, intercept or even attack commercial and military vessels passing through the Strait of Hormuz. This kind of threat is very real and by no means unusual as Iran is known to regularly swarm commercial and military ships with high-speed, maneuverable swarming groups of armed small boats.

While seemingly composed of only small boats, a collection or swarm of small attack boats do present a serious risk to large warships in a number of key respects. The tactical concept would be to attack a surface ship from so many angles at one time in order to overwhelm and break through ship defenses. Boats could be packed with explosives intended to collide with surface warships or fire anti-armor weapons from a large number of angles and locations at one time.

Given this tactical scenario, the US Navy has for many years been taking the small boat threat very seriously and made special efforts to engineer upgraded layered ship defenses in order to improve protections for larger-draft warships facing small boat attacks. Certainly the US Navy is well known for its well-evolved layered defense system against enemy anti-ship cruise missiles, ballistic missiles and even aerial drones, helicopters and fighter jets, yet many of these defenses may not specifically address closer-in surface threats.

Longer Range Threats

A US Navy destroyer SM-3, SM-6 and SM-2, for example, can rely upon ship based radar and fire control to track and intercept ballistic missiles from a wide range of distances. Newer advanced variants of the SM-3 such as the SM-3 Block IIA for example, can even track ICBM-type targets re-entering the earth’s atmosphere. The newest SM-3 Block IIA is larger, longer range and capable of improved guidance and target discrimination due to software upgrades. Using an aerial gateway to sense “beyond the horizon,” an SM-6 can track and destroy anti-ship cruise missiles from much safer stand-off distances. For example, the SM-6 provides the key building block for the Navy’s now-deployed Naval Integrated Fire Control - Counter Air system which forms a meshed relay of sensors, radar and threat indicators to alert ship-integrated command and control of approaching anti-ship cruise missiles from beyond the horizon.

Navy warships also operate the Evolved Sea Sparrow Missile Block II, a ship-fired interceptor capable of sea-skimming mode operating beneath the radar aperture emitting from enemy ships to intercept and destroy anti-ship missiles as well. In more recent years, new generations of technology are also greatly enhancing layered defenses, with weapons like lasers and EW increasingly capable of tracking and destroying incoming threats.

Closer In Threats

As part of this, the Navy has also for years been making modifications to ship defenses to ensure improved protection against surface threats, and small boats in particular. EW and lasers can be critical in these efforts, as they can potentially hit multiple targets at once at the speed of light or “jam” the rf signal or guidance systems of closer-in fired weapons or enemy communications networks. Also, as far back as 10 years ago, the Navy worked to be “in front” of the small boat threat and regularly conducted live-fire training exercises to approximate small boat attacks. Deck mounted guns were improved with guidance, suppressive fire, lethality and range, and defensive weapons such as Close-In-Weapons-System have been modified. CWIS, as its called, relies upon a Phalanx weapon to blanket an area with hundreds of interceptors to blanket an area with protection, intercept incoming munitions or drones or simply deny an air threat any ability to operate in close proximity to a surface warship. As far back as ten years ago, the Navy upgraded its CWIS weapons to a new “block ib” variant which added “surface” protection to what had been primarily an air-focused “area weapon.” This was both ground breaking and extended throughout the entire surface fleet, giving warships and ability to thwart, intercept, stop or destroy closer in surface threats such as surface drones and small boat swarms. The ability to blanket large surface areas with suppressive fire shooting hundreds of mini projectiles per minute could, at very least, complicate any efforts by small boats to succeed with an attack on a warship. Unmanned systems are also key to this equation as well, meaning they can perform forward surveillance at safer stand-off distances and, if needed, detect, intercept or stop attacking small boat swarms.

The IKE carrier therefore, could arguably be reasonably well positioned to defend a small boat threat by virtue of being flanked by several destroyers. Not only could the carrier launch aircraft in position to destroy small boat with precision targeting from the air, but nearby destroyers could encircle the carrier and use CWIS Ib along with other closer in interceptor weapons such as SeaRAM or Rolling Airframe Missile, both of which use fire control radar and threat tracking technology to attack closer-in threats.

No comments: