TOKYO: A collision warning system apparently was not working in Saturday’s crash of Japanese Maritime Self-Defense Force helicopters in the Pacific, Defense Ministry officials have said.

The ministry thinks that the two SH-60K helicopters are highly likely to have collided with each other in midair and crashed into the water off Torishima in the Izu Island chain south of Tokyo on Saturday night, based on radar records and the fact that their flight recorders were found in close locations. The MSDF is searching for seven missing crew members.

The two helicopters with a total of eight crew members aboard went missing during a nighttime antisubmarine exercise about 280 kilometers east of Torishima. One of the eight has been confirmed dead.

According to the ministry officials, SH-60K helicopters have a system to share location and other information while performing the same operation. The system gives a warning sound when the aircraft approach each other beyond a limit.

It is uncertain whether the system was working properly in the latest crash. The SDF does not oblige crew members to keep the system activated throughout an exercise.

When the system is not activated, crew members turn to anticollision lights on the aircraft, mutual radio communication and radar monitoring to avoid a collision.

However, a nighttime antisubmarine training carries risks as several aircraft repeatedly move and hover in a small space amid poor visibility.

A lack of monitoring and coordination was cited as the cause of a minor midair collision between MSDF patrol helicopters in 2021.

The MSDF is checking the flight recorders of the crashed SH-60K helicopters to analyze flight data and audio records.

The analysis is still underway, and there has been no sign so far indicating abnormality with the crashed aircraft, Defense Minister Minoru Kihara said Monday.

The MSDF has found fragments of the crashed aircraft and other items, while the main parts of the aircraft remain missing. It has not been confirmed whether floats of the aircraft used to land on water were properly deployed.

The depth of the water around the crash site is about 5,500 meters. “It’s not easy to salvage (the crashed helicopters),” an MSDF official said.

“We take (the crash) seriously and will use every means for the safe operation of SDF aircraft,” Prime Minister KISHIDA Fumio told a meeting of the Budget Committee of the House of Representatives, the lower chamber of parliament.

“We offer our sincere condolences over the death of the crew member. We’ll continue our all-our efforts to search for and rescue the missing people,” he also said.

Kihara told reporters that he has instructed the Ground, Air and Maritime SDF to ensure thorough safety management of their aircraft.

Jiji Press