An MV-22B Osprey lands abaord the amphibious transport dock ship USS New Orleans during Keen Sword drills in the Philippine Sea, Nov. 18, 2022. (Desmond Parks/U.S. Navy)

U.S. and Japanese pilots for the first time will fly Ospreys to Yonaguni Island, the Japanese territory closest to Taiwan, as part of upcoming military drills, according to a spokesman for Japan’s Joint Staff.

The tiltrotor flights are scheduled as part of civilian evacuation drills during the allies’ annual Keen Sword exercise taking place in October and November across Japan, according to the spokesman.

In another first, the U.S. Marines are planning to send a High Mobility Artillery Rocket System, or HIMARS, to Camp Ishigaki, a Japan Ground Self-Defense Force base on Ishigaki Island, through the civil airport, the spokesman said by phone Friday.

“We don’t know yet how many of them will be transported,” he said.

Some Japanese government officials are required to speak to the media only on condition of anonymity.

Ishigaki and Yonaguni, in the Yaeyama Islands, lie southwest of Okinawa and east of Taiwan. They could become contested ground in the event of a conflict with China.

Keen Sword is scheduled from Oct. 23 to Nov. 1, with 12,000 U.S. and 33,000 Japanese troops, 40 vessels and 370 aircraft, according to a Joint Staff news release Thursday. Australian and Canadian military units will also participate.

Training is planned at U.S. and Japanese bases, 12 commercial airports and 20 commercial seaports from Hokkaido to Okinawa, with most of the exercise taking place on Okinawa and at Kagoshima on Kyushu, the southernmost of Japan’s four main islands, the spokesman said.

During the training, a Marine MV-22 Osprey and a Ground Self-Defense Force V-22 Osprey are expected to fly to Yonaguni, 67 miles east of Taiwan, the spokesman said.

“We will conduct an evacuation drill, and the Ospreys are going to be used to evacuate people from the island to Naha,” the spokesman said.

No civilians will take part in the drill, a spokesman for the Joint Staff said Monday.

U.S. and Japanese Ospreys were grounded between December and March following a Nov. 29 crash of a U.S. Air Force Special Operations Command aircraft that killed all eight aboard. The accident investigation found a catastrophic mechanical failure at fault, compounded by a “lack of urgency” by the crew at the time, according to the accident report.

The revolutionary aircraft lands and takes off like a helicopter but flies as a fixed-wing aircraft.

Okinawa Gov. Denny Tamaki, for one, has objected to the Ospreys’ continued flights over Japan. The U.S. military has said the aircraft is safe to fly but will not operate within its full mission range until 2025.

Ground Self-Defense Force Ospreys also are expected to use Naha airport for the first time during the exercise, the Joints Staff spokesman said. They will fly from the airport to Yonaguni or Tokunoshima island northeast of Okinawa for training.

Planning is underway for the exercise and “an announcement is expected in the coming weeks,” 1t Lt. Owen Hitchcock, spokesman for the III Marine Expeditionary Force, said in an email Friday. He would not confirm details from the Joint Staff.

“For operational security reasons we will not discuss the extent of participation of U.S. forces or locations of operations until the exercise begins,” he wrote.

Keen Sword, a biennial exercise begun in 1986, is designed to increase combat readiness and improve the working relationship between U.S. and Japanese forces.

The exercise comes amid increasing tensions between Tokyo and Beijing. Chinese vessels frequently intrude into Japanese waters near the Senkakus, islets about 105 miles east of Taiwan that are administered by Tokyo but claimed by Beijing and Taipei.

A Maritime Self-Defense Force warship sailed through the Taiwan Strait for the first time on Wednesday, according to a Japanese media report. Earlier this month, a Chinese aircraft carrier sailed between Yonaguni and nearby Iriomote, entering the Japan’s maritime contiguous zone, according to the Defense Ministry.

The U.S. and Japan also are increasing their cooperation as China increases its military strength and asserts its claims on maritime territory in the South and East China seas.