Personnel at Wheeler Army Airfield near Honolulu told the Coast Guard that it lost contact with the crew of a UH-60 Black Hawk helicopter during a training exercise Tuesday night, the Coast Guard said in a statement.
Night training offshore is routine, said Lt. Col. Curtis Kellogg, public affairs officer for the Army's 25th Infantry Division.
The search began immediately after one aircrew lost visual and video contact with the other helicopter, Kellogg said.
Responding teams reported spotting a debris field about 2 miles west of Kaena Point, Oahu, shortly before 11:30 p.m., the Coast Guard statement said.
An airplane, two helicopters -- which are elements of the 25th Combat Aviation Brigade -- and several boats are being used in the search across an area with light winds and 2-foot seas.
Two Black Hawk crews were conducting training between Kaena Point and Oahu's Dillingham Airfield at the time communications were lost, officials said.
The UH-60 Black Hawk is a four-bladed, twin-engine utility helicopter manufactured for the Army by Sikorsky Aircraft starting in the 1970s.
Kaena Point is northwest of Honolulu.
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