Rachel Halterman, spokesperson for the National Transportation Safety Board (NTSB), said agency investigators met with emergency medical teams from the city, county and state and representatives of the airline, the plane's manufacturer and the pilots union to maximize the search for victims and clues from the crash.

The search of the crash site, roughly the length of three football fields, "will be an inch-by-inch thing," Halterman said from the NTSB's makeshift command center in the Sioux City Convention Center.

"The flight recorder will be going back to Washington sometime today and we'll start interviewing the crew and the survivors, eyewitnesses and everybody we can who has first-hand knowledge of the accident," she said. "We're also collecting maintenance records on the plane."

Before the crash, the pilot radioed to report that the 15-year-old jumbo jet experienced "complete hydraulic failure," Federal Aviation Administration spokesperson Fred Farrar said. Parts of the plane were found 50 miles away.

Hydraulic systems allow pilots to manipulate the wing and tail controls. Without them, aviation officials say, the plane would be uncontrollable.

Virginia Jane Murray, a flight attendant, survived by crawling out of an opening in the burning wreckage.

"She said she was tumbling," said her father, Don Murray of Chester, S.C. "The walls were coming in. She said a hole opened up and the sunlight came in and she climbed out the hole. She said she knew the Lord opened up that hole."