WASHINGTON — South Korea has grounded its fleet of F-35As after one of the aircraft had to conduct an emergency belly landing Tuesday.

Yonhap News Agency in Seoul reported that the F-35 was taking part in a training flight when it experienced issues with its avionics system. It was forced to land on its belly at Seosan Air Base south of Seoul when those problems caused the fighter’s landing gear to malfunction, Yonhap reported, citing officials there.

The pilot was unharmed, Yonhap reported. A fire engine had sprayed a special foam on the runway to keep the jet from sustaining serious damage during the skid.

South Korea’s air force plans to conduct a joint investigation with the U.S. military, Yonhap reported, and grounded its F-35A fighters in the meantime. South Korea plans to buy 40 F-35As in total, and has so far received more than 30 of them.

Lockheed Martin, which builds the F-35 Lightning II, said in a statement to Defense News it is “aware of the emergency landing that occurred Tuesday at Seosan Air Base and stand[s] ready to support the Republic of Korea Air Force.” The company referred further questions to South Korea.

This is apparently the first time an F-35 has conducted a belly landing, Yonhap reported.

Stephen Losey is the air warfare reporter for Defense News. He previously covered leadership and personnel issues at Air Force Times, and the Pentagon, special operations and air warfare at Military.com. He has traveled to the Middle East to cover U.S. Air Force operations.

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