US, partner nations sink 2 decommissioned American warships during RIMPAC

Multinational forces sent two decommissioned U.S. Navy warships to the bottom of the Pacific off the coast of Hawaii as part of the biennial Rim of the Pacific exercise.

A flurry of weapons fire from warships and aircraft from the United States and six participating nations sank the guided-missile cruiser USS Mobile Bay on July 12 and the amphibious assault ship USS Peleliu on July 17, the Navy said in a news release Thursday.

The two ships sank to a depth of 15,000 feet about 50 miles off the island of Kauai’s north coast.

RIMPAC, a biennial exercise billed as the largest international series of naval drills, includes 30 nations, 35 warships and more than 190 aircraft and 30,000 personnel this year. The exercise began June 24 and concludes July 31.

“Watching our Sailors work side-by-side with partners from around the world, executing complex maritime events together, is the strongest reminder of why these relationships matter,” U.S. Navy Vice Adm. Jeff Jablon, RIMPAC commander, said in the release. “[Sinking exercises] are a prime example of the strength and readiness our partnerships create.”

Among the participants were the Kentucky National Guard’s 623rd Field Artillery Regiment and the Japan Ground Self-Defense Force, who fired a High Mobility Artillery Rocket System, or HIMARS, from the Pacific Missile Range Facility at Barking Sands on Kauai, according to a separate U.S. 3rd Fleet news release.

“Few artillerymen ever have the privilege of conducting a combined live-fire exercise with another nation’s forces,” battalion commander Lt. Col. Tyler Brown said in the release. “While our equipment, procedures and even our languages may be different, our professionalism and dedication to our nations are the same.”

Navy and Air Force personnel and forces from Australia, Canada, Italy, New Zealand and Spain, including the Spanish air defense frigate Alvaro de Bazan, joined in the sinking exercise, according to the Navy.

The sinking is the second consecutive RIMPAC exercise to include two warships, following the 2024 sinking of the amphibious transport dock USS Dubuque and the amphibious assault ship USS Tarawa. Previous RIMPAC sinking exercises typically included just one “hulk.”

The 3rd Fleet did not immediately respond Thursday to an email requesting comment and additional details on the exercise.

Neither ship involved in the training was a stranger to the Indo-Pacific.

Tugboats escort the hulk of decommissioned amphibious assault ship USS Peleliu through Pearl Harbor, Hawaii, in preparation for a combined sinking exercise as part of Rim of the Pacific drills, July 15, 2026. (Nathan Cahall/U.S. Navy)

The Mobile Bay, a Ticonderoga-class cruiser, was homeported for years at Yokosuka Naval Base, home of the U.S. 7th Fleet.

Commissioned in 1987, the ship spent more than three decades in service and supported major operations, including Desert Shield, Desert Storm and Iraqi Freedom. It was decommissioned in August 2023.

The Peleliu, a Tarawa-class amphibious assault ship, was commissioned in 1980 and homeported with the 3rd Fleet in San Diego. The vessel supported Operation Enduring Freedom — it was the first ship to disembark Marines in Afghanistan — and Desert Storm and Iraqi Freedom.

Both ships were also involved in humanitarian missions, including relief efforts following the 1991 eruption of Mount Pinatubo in the Philippines.