New weapons and old warships: RIMPAC's dramatic sink test unfolds
One method to test the effectiveness of anti-ship weapons is to use them against real warships. During this year's RIMPAC exercises, the Americans sank two of their own decommissioned large ships – USS Dubuque and USS Tarawa.
RIMPAC (Rim of the Pacific) is an extensive international maritime exercise in the Pacific, organised by the United States since 1971. This year, for the exercises planned from 26 June to 1 August, the Americans invited as many as 29 other countries.
The manoeuvres involve 40 ships, 150 aircraft, and more than 25,000 soldiers from around the world. One part of the manoeuvres is SINKEX exercises, during which real weapons are used to attack real—although decommissioned—warships.
This year's exercises saw the use of new LRASM anti-ship missiles, and the maritime targets were attacked by, among others, F/A-18F Super Hornet carrier-based aircraft and B-2 Spirit strategic bombers.
Two decommissioned ships—USS Dubuque (LPD 8) and USS Tarawa (LHA 1)—were used as targets. Before sinking, both ships were prepared according to the Environmental Protection Agency (EPA) guidelines to minimise potential pollution in the exercise area. Removing fuel, ammunition, and flammable substances from the ships' interiors also made them harder targets to sink.
American regulations allow ships to sink, provided that the wreck settles at a depth of at least 1,800 metres (5,900 feet) and a distance of at least 80 kilometres (about 50 miles) from the shore.
Sunk amphibious ships
The ships sunk during the exercises were notable for their size. The USS Tarawa (Tarawa class) was a large amphibious ship with a length of 250 metres (820 feet) and a displacement of 39,000 tons. It featured a flight deck and hangar capable of handling 35 helicopters and eight vertical/short takeoff and landing aircraft.
The ship could transport up to 1,800 Marine Corps soldiers and equipment, and a good deck facilitated amphibious operations—hovercraft, amphibious vehicles, and various landing craft could depart directly from the ship's interior. Five ships of this type were built.
The USS Dubuque (Austin class) displaced 17,000 tons and could transport 840 Marine Corps soldiers. It also had a good deck and a flight deck and was equipped to handle up to six large helicopters. A total of 12 ships of this type served in the US fleet.