Some U.S. military Osprey aircraft took to the air in Okinawa, southern Japan, on Thursday, amid lingering local concern over the safety of the tilt-rotor military planes following a crash last year.

The resumption of flights in Japan came after Washington last week lifted a worldwide flight ban on U.S. Ospreys, imposed after a U.S. Air Force CV-22 transport plane crashed off a southwestern Japan island on Nov. 29, killing all eight crew aboard.

An MV-22 Osprey aircraft takes off from U.S. Marine Corps Air Station Futenma in Okinawa Prefecture on March 14, 2024. (Kyodo)

Some Ospreys' engines were started around 8:30 a.m. at Marine Corps Air Station Futenma, with the aircraft beginning to take off from around 8:50 a.m.

The U.S. Marine Corps' III Marine Expeditionary Force said in a press release that it "deemed the aircraft safe to fly based on a meticulous and data-driven approach prioritizing flight worthiness and safety."

The U.S. military "conducted a thorough and deliberate formulation of risk mitigation controls" to assist with the safe return of the Ospreys to their operations, the Okinawa-based unit said.

In Japan, the U.S. military has deployed 24 MV-22s, used by the Marine Corps, at the Futenma air station, and five CV-22s, used by the Air Force, at Yokota Air Base in the western suburbs of Tokyo.

On Wednesday, Japanese government officials explained the plan to fly Ospreys again in Japan as early as Thursday to local authorities in several prefectures, including Okinawa, but faced strong opposition due to a continuing lack of information about the accident's cause.

The United States grounded all of its Ospreys across the world on Dec. 6, a week after the accident took place near Yakushima Island in Kagoshima Prefecture during an exercise. Last Friday, it removed the flight ban without publicly revealing the cause of the incident.

Masanori Matsugawa, mayor of the Okinawa city of Ginowan where the Futenma base is located, told reporters it is "disappointing" that U.S. forces resumed Osprey flights without explaining what caused the accident, adding it left local citizens feeling anxious.

A U.S. military Osprey aircraft flies over Naha, the capital of Okinawa Prefecture, on March 14, 2024. (Kyodo)

"We go back to living in fear of (Ospreys) crashing. Enough is enough," said Kenei Yamashiro, 85, who lives near the Futenma base.

Chief Cabinet Secretary Yoshimasa Hayashi told a press conference that some local governments have "reacted harshly" to the resumption plan and pledged that the central government will make efforts to dispel local concerns.

Japan's Ground Self-Defense Force also has 14 V-22 Ospreys at their current temporary deployment site in Kisarazu, near Tokyo. They have been grounded since the November incident.

The cause of the crash in November has been identified but cannot be made public due to restrictions under U.S. domestic law until the U.S. side issues a report on it, according to Japanese Defense Ministry officials.

The crash was the deadliest ever involving Ospreys, which are capable of taking off and landing like a helicopter but cruising like a plane, since their combat debut in 2007.

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