DILLINGHAM, ALASKA (AP) -- Federal investigators say the plane carrying former Sen. Ted Stevens crashed into a mountain with such force that it left a 300-foot gash on the slope.

NTSB chairwoman Deborah Hersman provided new details about the Monday crash in a rugged section of Alaska.

She said the group had left a lodge for a salmon fishing camp and crashed about 15 minutes later. A doctor and two EMTs were flown to the scene three hours later and tended to the injured during a damp and chilly night.

Hersman said the 1957 plane was overhauled in 2005 and flown by a pilot with 29,000 hours of flight time.

The crash killed Stevens and four others. Four people survived, including former NASA chief Sean O'Keefe.

Click here to read more about Sean O'Keefe, and his time as a professor at Syracuse University's Maxwell School.

(Copyright ©2010 by The Associated Press. All Rights Reserved.)