HONOLULU -- A 10- by 40-foot hole ripped open around a cargo door of a United Airlines jumbo jet with 354 people aboard early Friday, sucking out nine people to their deaths 23,000 feet above the Pacific Ocean and injuring at least 21 others.
The airplane, bound for New Zealand and Australia, managed to fly the 100 miles back to Honolulu on two of its four engines. Rescue ships and aircraft were sent to search the Pacific in the area where the plane turned back.
Passengers described hearing an explosion, and investigators tried to determine whether the damage was caused by a bomb or by structural failure on the 18-year-old Boeing 747.
A law enforcement official in Washington who requested anonymity said an initial examination of the jetliner indicated that 'there was a big hole, but it was not an explosive tear (in the fuselage) in appearance.'
The hole followed 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.
Owen Miyamoto, adminstrator of the Department of Transportation, said during a news conference that 'several rows of seats' had been ripped from the airplane. He said the seats 'apparently (were) lost when the floor failed and when the side was lost.'
Eugene Glenn, head of the FBI office in Honolulu, said his agency was investigating the possiblity of a bomb blast, but both he and Miyamoto emphasized that there was no specific bomb threat against flight 811.
In addition, the regular, rectangular shape of the hole 'would suggest' that a bomb was unlikely, Glenn said. Forty FBI agents interviewed more than 300 passengers and crewmembers, Glenn said.
'After the specialists have arrived and they examine the area, then a valid judgment can be made,' Glenn said.
Dan Ohshita of KOHO radio said he received a telephone threat Jan. 23 from a caller speaking 'beautiful Japanese' who said, 'If Maruoka Osamu of Japan's Red Army is not released by Feb. 24 (the date of Emperor Hirohito's funeral) there will be a bomb explosion on an American airline.'
In March 1987 a cargo door on a Boeing 747 partially opened in flight because of a damaged lock, and 16 months later the FAA issued an 'air worthiness directive' requiring airlines to promptly inspect cargo doors on Boeing 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 an FAA flight directive concerning 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.
A passenger, Bruce Lampert, an aviation lawyer from Denver whose firm has handled air crashes, dismissed early speculation of a bomb aboard the plane and suggested metal fatigue. '(I'm) seriously concerned as to what appears to be a problem of metal fatigue in America's air fleet,' he said.
Passenger Gary Garber said some people were 'blown out' of the plane.
'There was an explosion on the plane, in the business section, probably right above the cargo area,' Garber told CBS News. 'We were in the center section of the plane and the people at the aisle section - about four, six of them, whatever -- were blown out of the plane and I presume they're lost.
'That was maybe about a foot and a half away from our seats in the center section. We just hung on for dear life until the pilot made it back,' Garber said.
Another passenger, Beverly Nisbet, 50, who was on her way home with her daughter to Hastings, New Zealand, said she 'noticed a slight change in the engine sound and almost at the same moment there was the explosion. ... I believe some people were sucked out, but I don't really know.'
'We all quickly put on our life vests and just stayed belted and silently prayed,' Nisbet said. There was 'a bit of panic' among the passengers. 'We all thought our time had come.'
The blast caused the interior wall to blow into the plane, Nisbet said, and there was 'debris flying around. ... One girl was screaming a lot. One very brave man picked her up, took her to the back of the plane and calmed her down.'
A Coast Guard plane, a helicopter, three cutters and the USS Coronado were sent to the area to search for debris and possible survivors. Coast Guard spokesman Dave Goff said debris was found just before 11 a.m. local time (4 p.m. EST) by a C-130 inside the 120-square-mile search area.
The FBI was investigating along with a 14-member National Transportation Safety Board team sent from Washington, D.C., to Honolulu.
Flight 811 was less than 20 minutes into its flight to Auckland, New Zealand, when the pilot reported a loss of power in one of his four engines. He turned around and managed to land the crippled jetliner, which carried 336 passengers and a crew of 18, at 2:33 a.m. local time (7:33 a.m. EST) at Honolulu International Airport, where the remaining passengers were evacuated.
Drucella Anderson, an NTSB spokeswoman in Washington, said the plane was 17 minutes into its flight when the 'pilot heard an explosion ... (and) he lost the Number 3 engine.' The jetliner was at 23,000 feet altitude and still climging at the time of the accident, said Lawrence M. Nagin, a United spokesman.
Boeing noted that 23,000 feet altitude creates for the 747 its 'maximum pressurization differential,' or the greatest difference between the high pressure inside the cabin and the low pressure outside.
As the jetliner made its emergency landing, power was lost in the No. 4 engine, leaving only the two engines on the left wing functioning.
Mary Flynn, a deputy Honolulu medical examiner, said her department 'recovered multiple small body fragments and pieces of clothing from the No. 3 engine of United Flight 811.'
Kali, the Hawaiian Department of Transportation spokeswoman, said the first engine apparently was lost when the blast knocked off the right front cargo door.
The explosion also ripped a 10- by 40-foot hole in the foward baggage area on the right side of the plane. 'Through the hole you can see the seats of the first-class section,' Kali said.
FAA spokeswoman Theresa Greco in Washington said the pilot radioed air traffic controllers after losing power in the No. 3 engine and, after declaring an on-board emergency, descended to 4,400 feet.
Kali said about a dozen people, some suffering broken arms and legs, were taken to Honolulu hospitals. A canvassing of area hospitals by United Press International indicated at least 21 passengers treated for injuries.
'Many of (the injuries) may have been suffered (as passengers used) the exits down the chute,' she said.
United Airlines, which early in the day had said 16 passengers were unaccounted for, later lowered the figure to nine. 'We needed a bit of time to account for everybody,' United spokesman Russell Mack said.
Boeing said the plane was delivered to United Airlines on Nov. 3, 1970. It was the 89th 747-100 built, out of a total of 205. It was the sixth of that model delivered to United.
Boeing and Pratt & Whitney of Hartford, Conn., the manufacturer of the plane's engines, both sent investigators to Honolulu. Boeing said it was checking records to determine how many takeoff-landing cycles the plane had, as well as any records for heavy duty maintenance work on the plane.
In Washington, Rep. James Oberstar, D-Minn., chairman of a House aviation subcommittee, said preliminary information indicated the accident was caused by structural problems, not a bomb. 'I think you would be looking at internal structural failure along the fuselage,' Oberstar said.
Oberstar, who was briefed on the incident by aviation officials, said maintenance workers may have failed to identify a weakness along the rivet lines, although he emphasized United has a very good maintenance program.
A spokesman for Pratt & Whitney said the jetliner was equipped with a version of the Pratt & Whitney JT9D engine that was developed in the 1970s.
Arthur Wolk, an aviation expert in Philadelphia, said a blade from one of the plane's engine may have ripped into the fuselage. He also said the plane's design had 'inadequate containment. ... There's no way the hole should have become so big.'
A White House spokesman said President Bush had been told about the incident. 'The FAA, with the FBI in support, are conducting an inquiry into the incident involving the United Airline flight from Honolulu to Auckland, New Zealand,' he said. 'The facts are not clear yet and it is premature to speculate.'
Flight 811 originated in San Francisco and stopped to pick up passengers in Los Angeles. Authorities there also were investigating to determine whether the cause of the explosion could be traced back to Los Angeles.
The last major aviation incident in Hawaii occurred April 28, 1988, 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.
The NTSB delayed a vote scheduled for this month on the probable cause of the Aloha accident. The ruling, a spokesman said, may not be made until April. Investigators found evidence of metal fatigue and cracking around some of the plane's rivets, and the accident was unofficially blamed on structural failure.
In the worst single plane disaster in aviation history, 520 people died Aug. 12, 1985, when a Japan Air Lines Boeing 747 slammed into a mountainside in central Japan. The jumbo jet had lost parts of its tail section before the crash due to a faulty repair on the bulkhead.