A deliberate full-size ship sinking is among the few means of demonstrating that a modern scheme of “ship-kill” is both end-to-end, i.e. in detecting the target and the characteristics of the weapon attack, as well as in its ability to exert weapons on actual structure and flooding behavior. This is the technical rationale of the RIMPAC 2024 SINKEX activities off Hawaii, whereby retired amphibious warships served as controlled deep water instrumented warship targets.
The retired USS Dubuque (LPD-8) and USS Tarawa (LHA-1) were sunk in an assigned location deep in water of approximately 15,000 feet in a location over 50 miles north of the island of Kauai. Practically, such depth is significant: it minimizes the dangers of navigation and forms a carefully regulated field, in which militaries will be able to specialize in the weapon-target interaction instead of trying to bring ships back to the surface or clearing them of debris.
Spectacle is accidental in a SINKEX. The main deliverable is data. A big hull adds real-life complexity that cannot be well simulated in simulation: layered compartments, redundancy, air-trapping voids, members of the structure that do not react in the same way to repeated hits. Such details determine whether a weapon has been successful in creating a “mission kill” or causes the type of progressive flooding that results in a ship settling and then sliding under the surface. Prior to any of this, the targets have been prepared in terms of environment to eliminate regulated hazards like PCBs and petroleum products, a process which highlights how much logistical preparation is required before the first shot is made. The outcome is a unique live laboratory in which allied forces have the opportunity to test what counts hit placement, fuse action, blast couple into structure and what the survivability characteristics of a damaged ship really perform like at realistic loads.
The most notable aspect of the Tarawa incident was the deployment of AGM-158 C Long Range Anti-Ship Missile. The weapon came off one of an F/A-18F Super Hornet of the U.S. Navy, which placed a carrier-air “truck” and a standoff cruise missile to seek and classify its targets with a passive seeker and onboard programming instead of being guided by a continuous external signal. That missile family has been also linked to operational stockpile activity through a Pentagon budget reprogramming report, which also underscores a bigger fact: high-end munitions are not inexhaustible, and training, readiness, and actual world demands is all competing on a similar inventory.
The other significant strike thread by RIMPAC was oriented elsewhere: cheaper, flexible effects. The U.S. Air Force showed QUICKSINK a method where a JDAM-based guidance package is combined with detectors that can push the detonation towards a waterline of the ship where flooding and propulsion loss may spread rapidly. It is an engineering effort to make a family of weapons commonly available in a convenient way a maritime general-purpose solver of problems, and it rewards the accuracy of geometry, rather than the weight of warhead.
This is all also dropped at a time of transition of the launch platforms. The Super Hornet continues to be the mainstay of naval aviation but the production cycle of the aircraft is on the verge of being shut down, with Boeing indicating that last deliveries would be in 2027. This places additional pressure on modernization, networking, and weapon integration to make the current jets usable, particularly when the payload and range that the munition delivers, as well as its survivability, are becoming more and more the defining aspects of the engagement.
The 2024 RIMPAC exercise, as it were, was not so much about sinking relics as proving one modern formula; stealthy standoff missiles against complex surface targets, versatile guided bombs against defeating enemy ships with a “good enough” hand, and allied crews working out the communications and coordination to make one work or the other happen.
According to the U.S. Navy Vice Admiral John Wade, the commander of the RIMPAC 2024 Combined Task Force, sinking exercises provide an opportunity to practice our skills and learn together and get a real-life experience.
