Sandy Dahl, the widow of a pilot who died in the Sept. 11, 2001, terror attacks, has died.

Dahl, 52, passed away in her sleep, said family friend David Dosch, according to the Denver Post.

'I want to make sure history is written.'

- Sandy Dahl

Dahl's husband, Jason, was the captain of United Flight 93 on 9/11, when passengers fought back against terrorists and kept the plane from crashing into the U.S. Capitol or the White House. The plane crashed in a field in Shanksville, Pa. 

After Jason's death, Dahl became a public face for all grieving 9/11 families, the paper reports.

She founded a scholarship fund in her late husband's honor to provide funding for young pilots to receive their education.

"They did what would almost never be asked of anyone," Dahl told The Denver Post last year. "I want to make sure history is written."

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