HONOLULU -- Aviation experts Saturday scrutinized the United Airlines jumbo jet that lost its cargo door 23,000 feet above the Pacific Ocean, while ships and aircraft searched for debris and signs of the nine victims sucked out of the gaping hole in the fuselage to their deaths.
Nine passengers were blown out of the plane and at least 21 others were injured when a 10-by-40-foot hole ripped open around a cargo door shortly after Flight 811 took off with 354 people aboard bound for Auckland, New Zealand, early Friday.
Federal investigators said they would not focus on any particular theory of what caused the disaster, although speculation from other authorities has concentrated on the possibility of structural failure.
'The doors are all completely wide open,' Lee Dickinson of the National Transportation Safety Board told reporters at his headquarters at the Outrigger Prince Kuhio Hotel in Waikiki of the possible causes.
'We are proceeding as if we know nothing. We are starting at ground zero ... collecting all information we possibly can. Our job is collect thorough, complete, and accurate information' for analysis in Washington, he said.
'The purpose of being here is not to determine a probable cause,' Dickinson said. 'You will not hear me say one time what the probable cause is because we don't do that.'
Dickinson said, however, he would brief reporters on the progress of the investigation at a meeting Saturday night.
The safety board held an organizational meeting earlier Saturday attended by 70 to 100 people, including the 16 safety board personnel and other parties involved in the investigation, including the FBI and bomb experts from the Federal Aviation Administration, United, Boeing, Pratt-Whitney engine company, and the airline pilots and flight attendants associations.
'We also organized six groups ... to go out to the accident site and begin investigating in their specific areas,' he said. The groups would cover operations, survival factors, structures and metallurgy, maintenance records, and engines and power plants.
The operations group would cover the history of the flight. The survival factors group would document information from the cabin area and cockpit such as floor buckling and seat removal.
A sixth group would be formed in Washington to investigate the cockpit voice recorder/flight data recorder. Officials hoped to begin reading out the voice recorder at the beginning of next week.
United Airlines spokesman William Speicher said he expects the plane will be fully repaired and put back into service unless federal authorities say otherwise.
He said there had been no flight cancellations as a result of the tragedy, and it has been 'business as usual' at the ticket counter.
The Coast Guard and Navy, meanwhile, resumed their search over a 1,000-square-mile area of the Pacific on the chance of locating the bodies of the nine passengers sucked out of the Boeing 747 when it ripped open less than 30 minutes after taking off early Friday.
The search 100 miles south of Oahu -- which had turned up two airplane seats, a shoe, a 4-by-6-foot piece of metal and several emergency escape pamphlets usually found tucked into the back of seats - involved three cutters, the USS Coronado, three helicopters and a cargo plane.
Although federal officials said it was too early to rule out foul play, most experts, including a law enforcement official in Washington who requested anonymity, agreed the incident aboard the 18-year-old jet was not the result of 'an explosive tear.'
Speculation centered on the possibility of a failed cargo door, a structural failure in the fuselage or the possibilility that an explosion in an engine had caused part of the engine to pierce the fuselage.
The findings of the safety board investigation are crucial to Boeing, which has experienced difficulties with aging aircraft and has been troubled as well by miswired emergency systems in newer planes and by 747 production delays.
The plane's age may have been a factor in the incident. Boeing said the aircraft was nearing the end of what it calls the 'economic service life' of its planes.
A number of the 336 passengers and 18 crew members aboard the jet reported hearing an explosion as the huge hole opened up around the cargo door 17 minutes into the flight.
The pilot, Capt. David Cronin, a 34-year United veteran, nursed the crippled jet the 100 miles back to Honolulu on two of its four engines after descending to 4,400 feet.
The hole follows the outline of the cargo door, extending from the baggage compartment up through the passenger area to the ceiling, Hawaii Department of Transportation spokeswoman Marilyn Kali said.
The Honolulu Medical Examiner's office found grisly evidence that a body or bodies had been sucked into an engine on the right side of the aircraft. Dr. Mary Flynn said body frangments and pieces of clothing were recovered from the No. 3 engine, one of the two that failed in the disaster.
Eugene Glenn, head of the FBI office in Honolulu, said his agency was investigating the possibility of a bomb blast, but emphasized there was no specific bomb threat against Flight 811.
In addition, the rectangular shape of the hole 'would suggest' that a bomb was unlikely, Glenn said.
One of the passengers, Bruce Lampert, an aviation lawyer from Denver whose firm has handled air crashes, suggested metal fatigue was at fault. 'The blowout was too regular in shape to be an explosion. My feeling is it was a failure in the cargo door itself,' he said.
In March 1987, a cargo door on a Boeing 747 partially opened in flight because of a damaged lock. Sixteen months later the Federal Aviation Administration issued an 'air worthiness directive' requiring airlines to promptly inspect cargo doors on 747s and to reinforce their locks with steel plates within 24 months.
Russell Mack, United's vice president for corporate communications, said the airplane 'was in complete compliance with all maintenance requirements,' including the FAA-ordered reinforcement of the cargo door.
Lawrence Nagin, a senior vice president for United, said the plane had logged 58,815 hours and 15,021 takeoffs and landings.
Despite the jarring experience, 247 of the passengers boarded a special United flight for Auckland Friday night. A number of other passengers left later on the same flight -- Flight 811 -- that they had taken the previous night.
The nine passengers killed included six Americans, two Australians and a New Zealander.
The last major aviation incident in Hawaii occurred last April 28 when the top of an Aloha Airlines Boeing 737 blew away at 24,000 feet. A flight attendant was sucked out of the plane and killed. The aircraft landed 15 minutes later at Kahului Airport on Maui.