WASHINGTON, Oct 21 (Reuters) - The chair of the National Transportation Safety Board said Tuesday a weather balloon may be responsible for cracking a United Airlines UAL.O windshield at 36,000 feet, prompting emergency landing.

WindBorne said in a statement late Monday that it believes it was one of its balloons that struck the United Flight 1093, a Boeing 737 MAX, on Thursday over Utah. NTSB Chair Jennifer Homendy said it had received the report from the company and is looking at it has part of the investigation. She said the incident "could have been really devastating for the aircraft and those on board."

(Reporting by David Shepardson)

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