Dahl, 52, was found dead in her home in Colorado on Friday. Jefferson County Deputy Coroner Carl Blesch said yesterday that there was no indication of foul play.
Dahl worked tirelessly running the Captain Jason Dahl Scholarship Fund and her death was a surprise, CNN quoted David Dosch, a family friend as saying.
"Sandy was instrumental in the creation of the Dahl Fund following the tragic events of 9/11, and her guiding light will be missed," the fund said in a statement posted on its website.
She died in her sleep from natural causes, it said.
The scholarship fund gives money to aspiring pilots to help them attend commercial flight training schools.
Jason Dahl was piloting United Flight 93 on September 11, 2001 when it crashed in a field in Shanksville, Pennsylvania. It is believed that passengers aboard that flight thwarted a plot to steer the plane through the US Capitol dome and eventually caused it to crash in a field.
