U.S. agency opens probe into United flight that lost altitude near Hawaii

WASHINGTON, Feb 14 (Reuters) - The National Transportation Safety Board said on Tuesday it would investigate a Dec. 18 incident in which United Airlines (UAL.O) Flight 777, a Boeing (BA.N) 777 jet, lost altitude before recovering shortly after departing Kahului, Hawaii.

The Air Current, an aviation news website, first reported the incident on Sunday involving the San Francisco-bound United plane, saying it dropped sharply to within around 800 feet of the Pacific Ocean before recovering and landing safely.

The incident is among a number of potentially dangerous events reported among U.S. passenger airlines in recent months, including two near misses last month at New York's JFK and Austin-Bergstrom airport in Texas that the NTSB is also probing.

Flightradar24, an aviation website, said the Dec. 18 United flight departed normally until "71 seconds after take off when the aircraft entered a steep dive. The aircraft descended from 2,200 feet to just 775 feet before recovering."

The FAA said the United Airlines flight crew reported the incident to the agency "as part of a voluntary safety reporting program. The agency reviewed the incident and took appropriate action." It did not elaborate.

United said the pilots filed the appropriate safety report after landing and the carrier closely coordinated with the FAA and a pilots union "on an investigation that ultimately resulted in the pilots receiving additional training."

United said the pilots fully cooperated with the investigation and their training program is ongoing. The two pilots involved have approximately 25,000 hours of flying experience between them.

Reporting by David Shepardson; Editing by Leslie Adler and David Gregorio

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