The Pentagon says that personnel on the Wasp class amphibious assault ship USS Boxer knocked down an Iranian drone that came within a “threatening range” as the ship sailed through the volatile Strait of Hormuz. Subsequent reports said that a U.S. Marine Corps all-terrain vehicle with an anti-drone detection and jamming system sitting on the ship’s flight deck brought down the unmanned aircraft with an electronic warfare attack.
President Donald Trump was first to announce that Boxer had taken defensive action in the Strait of Hormuz during a press conference at the White House on July 18, 2019. The Pentagon subsequently released a statement regarding the incident. The amphibious assault ship, which is carrying elements of the 11th Marine Expeditionary Unit, was sailing in a convoy at the time that also included a Harpers Ferry class dock landing ship, an Arleigh Burke class destroyer, and the expeditionary sea base USS Lewis B. Puller, a highly specialized vessel the War Zone has profiled in-depth in the past. A Henry J. Kaiser class underway replenishment oiler was also present for at least a portion of the voyage. The first-in-class USS Harpers Ferry was likely the dock landing ship that was sailing with Boxer as that ship is presently assigned to the Boxer Amphibious Ready Group. Puller, one of the Navy’s main anti-mine warfare platforms, which is capable of supporting MH-53E Sea Dragon mine-sweeping helicopters, is permanently deployed to the Middle East region.
Even without external weapons, the drone could have presented a real threat to the Boxer and personnel on board, either by acting as a loitering munition or otherwise harassing or interfering with the ship’s operations, especially the launch and recovery of any aircraft or helicopters from its flight deck. A mass drone attack, to say nothing of one from an actual swarm of unmanned aircraft networked together, could overwhelm the defenses on even the most heavily defended ship and wreak havoc.
CNN initially reported that personnel used a “soft-kill” electronic warfare attack rather than a missile, such as the ship’s RIM-116 Rolling Airframe Missiles (RAM), or a gun system, such as the Phalanx Close-in Weapon System (CIWS). Fox News then subsequently reported that the system in question was the Marine Corps’ new Light Marine Air Defense Integrated System (LMADIS). Pictures the Navy has released of the Boxer making the transit in the Strait of Hormuz already showed a specially configured 4×4 Polaris MRZR associated with LMADIS on the ship’s forward flight deck.
LMADIS, which you can read about in more detail in this past widely circulated War Zone piece, consists of a pair of MRZRs, both of which are equipped with the RADA RPS-42 hemispheric air surveillance active electronically-scanned array (AESA) radar system. One them also has a CM202 sensor turret with electro-optical and infrared full-motion video cameras. The CM202 offers an additional means of positively identifying potential threats that the RPS-42s detect.
If it becomes clear that the target is hostile, Marines can then use a Modi jammer to disrupt the drone’s links to its ground control station, potentially causing it to crash. The Marine’s specifically developed LMADIS to respond to the ever-growing threat of small unmanned aircraft. In January 2019, USS Kearsarge, another Wasp class ship, deployed the same system as it passed through the Suez Canal.