USS Theodore Roosevelt sails with Japanese, Australian, Canadian and French warships in Keen Sword

The aircraft carrier USS Theodore Roosevelt and its escorts sailed in formation with Japanese, Australian, Canadian and French warships in the Philippine Sea on Wednesday 21 October, as the US-Japan exercise Keen Sword 27 moved out to sea. Imagery released by the US Navy showed the carrier and the cruiser USS Chosin steaming with the Japanese helicopter destroyer JS Ise, the destroyers JS Kongo and JS Asahi, the Australian frigate HMAS Stuart, the Canadian frigate HMCS Regina and a French frigate, USNI News reported.

The Theodore Roosevelt strike group is made up of the carrier with Carrier Air Wing 11 embarked, the cruiser Chosin and the destroyer USS Decatur. It had stopped at the US Navy base at Yokosuka for a port visit from Friday 16 October and sailed again on Monday, the day the exercise began. The US Navy describes Keen Sword as a routine exercise held every two years to raise readiness and interoperability between US forces and the Japan Self-Defense Forces, with other partners taking part.

Figures for the size of this year's drills vary slightly between accounts. Citing a US Navy release, USNI News put participation at about 45,000 Japanese personnel and 11,000 US troops, with 260 aircraft and 40 ships. The Defence Blog gave about 12,000 Americans and close to 300 aircraft and ships in total. Australia, Canada, France, New Zealand and the Philippines are sending forces, while South Korea and the United Kingdom have sent observers. The exercise began on 19 October and is scheduled to end on 29 October.

Aboard the carrier, the US Navy is using the drills to show allies a new way of organising information warfare. On 20 October the commander of Information Warfare Squadron 9, Captain Edward McLellan, met Japanese and Australian naval personnel on the ship to explain the unit, which pulls a strike group's information warfare functions under one commander to speed up decisions. Japanese sailors have also been embarked to watch flight deck operations, according to USNI News.

In the air, US Air Force F-22 Raptors from the 525th Expeditionary Fighter Squadron are flying from the Japan Air Self-Defense Force base at Tsuiki on Kyushu. The Defence Blog reported that the stealth fighters deployed from Joint Base Elmendorf-Richardson in Alaska and were photographed at Tsuiki on 19 October, the opening day. KC-135 tankers and a C-130J transport have also arrived for the exercise. A separate air combat event links US F-35 simulators with live Japanese F-35 fighters and E-2 early warning aircraft in a shared defensive counter-air scenario.

On the ground, US Marines from Marine Wing Support Squadron 172, airmen from the 18th Wing and Japanese soldiers practised rapid repair of a damaged runway at Kadena Air Base on Okinawa on 20 October, combining the two countries' manual and machine methods to cut the time the work takes. The US Navy release quoted by USNI News said the aim was to repair airfields faster under contested conditions.

The Defence Blog noted that Japan's Joint Staff has said the drills are spread across Japanese and US military facilities, civilian airports and ports, and the sea and airspace around Japan. The carrier formation on 21 October brought the naval side of the exercise together in the open waters of the Philippine Sea, east of Japan's southwest island chain.