MANILA, Philippines – The 346 passengers were cruising at 29,000 feet Friday when an explosive bang shook the Qantas jumbo jet. The plane descended and oxygen masks popped from the ceiling as debris flew through the cabin from a hole that had suddenly appeared in the floor.

After an emergency landing, they saw how lucky they had been: A hole the size of a small car had been ripped into the Boeing 747-400 and penetrated the fuselage.

AP

An airline mechanic walks past the damaged right wing fuselage of a Qantas Airways Boeing 747-400 passenger plane following an emergency landing at the Ninoy Aquino International Airport Friday July 25, 2008 in Manila, Philippines. The plane, with 350 passengers and 19 crew, was enroute to Australia from London when a loud bang punched a hole in the right wing fuselage, passengers said.

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The eerie scene aboard Flight QF 30, captured on a passenger's cellphone video-camera, showed a tense quiet punctuated only by a baby's cries as passengers sat with oxygen masks on their faces. The jerky footage showed a woman holding tightly to the seat in front of her as rapidly approaching land appeared through a window. Loud applause and relieved laughter went up as the plane touched down.

There were no injuries and only a few cases of nausea, airline officials said. An official of the U.S. Transportation Security Administration said initial reports indicated no link to terrorism.

The passengers and crew arrived in Melbourne on a different plane Saturday morning and were greeted by hundreds of relieved family members.

Investigators appeared to be focusing on a structural problem.

"From the pictures that we've seen out of Manila during the course of the day, it would seem that one of the panels to the outer skin of the aircraft has literally come away from the rest of the fuselage," Chris Yates, a Jane's aviation expert, told The Associated Press.

While it is not uncommon for metal panels to be lost from aircraft in flight, he said: "It's relatively rare that when a bit falls off the airplane it causes the sort of instance that we saw in relation to Qantas. In other words that it causes the aircraft cabin to depressurize."

Mr. Yates said investigators will examine closely the fracture points that showed up on the skin of the aircraft to determine whether metal fatigue or manufacturing defect caused the panel to peel away.

Boeing spokeswoman Liz Verdier said it was too soon to determine what caused the hole, but the company was providing technical assistance as part of an investigation led by the National Transportation Safety Board.

Boeing and the safety board said Friday that they were sending teams to aid in an investigation by the Australian Air Transport Safety Bureau. Under international treaty, the U.S., as the country where the plane was built, will be an official participant in the investigation.

The plane had recently undergone a major overhaul, in which engineers discovered a great deal of corrosion inside the cargo hold, The Daily Telegraph of Australia reported in today's editions.

The Associated Press,

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