TOKYO_A massive fuel leak could have triggered the explosions that ripped apart a China Airlines jet in southern Japan just seconds after its passengers fled to safety, aviation officials said Tuesday.
The 157 passengers and eight-member crew on board slid down inflatable flutes and jumped out of windows in a dramatic evacuation moments before flames engulfed the Boeing 737-800 at Okinawa's Naha airport on Monday.
Authorities said they were focusing on evidence - backed up by sightings from ground engineers - that the stricken plane's right engine leaked a large amount of jet fuel as it pulled into a parking spot after arriving from Taiwan.
"From the size and intensity of the fire, we may be looking at a very large fuel leak," said Hiromi Tsurumi, a spokesman with Japan's Aircraft and Railway Accidents Investigation Commission.
News reports said damage to the pylon connecting the plane's engine to the right wing could have punctured a key fuel pipe, causing fuel to rush into the engine and ignite.
The jet was carrying some 4.7 metric tons (5.18 tons) of fuel when it landed, according to the Yomiuri newspaper. Authorities were also investigating whether any loose plane parts could have been sucked into the engine, damaging the fuel pipe.
Meanwhile, Taiwan's Civil Aviation Authority said the plane had suffered problems with a sensor connected to one of its wings earlier this month. The problem recurred the next day and was unrelated to Monday's explosion, according to the authority.
A joint investigation by Japanese, Taiwanese and U.S. aviation experts was slated to begin Wednesday, Japan's Transport Ministry said. Boeing is also dispatching an investigator to Japan, according to company spokesman Jim Proulx.
China Airlines president Zhao Guo-shi said Tuesday that he was sorry and embarrassed at the incident.
"What's important is that our passengers forgive us," Zhao told broadcaster TV Asahi after boarding a busload of Taiwanese tourists to apologize directly.
The tourists later waved red envelopes containing US$100 dollars they said Zhao had given them in compensation.
"I'm not satisfied. This is not enough to replace my luggage destroyed in the fire," one female tourist told the broadcaster.
Still, airline officials praised the plane's pilots for the quick evacuation. The entire operation took just three minutes after ground crew told the pilot they spotted fires on the jet's wings, according to airline spokesman Johnson Sun.
Pilots Yu Chien-kuo and Tseng Ta-wei jumped from the plane's two-story cockpit window after making sure all passengers had been evacuated.
"I saw flames coming from the left, so I escaped from the right," a jubilant Yu told reporters at a press conference Tuesday. "After I jumped, my mind went blank."
The fire started in one of the engines as the plane pulled into place at Naha airport, officials have said. With the plane's wings and midsection ablaze, the passengers fled to the tarmac on inflated emergency chutes.
Just minutes later, as the pilots scrambled out of a cockpit window, the jet erupted in a fireball that billowed flames and black smoke.
No one was injured. Two passengers were hospitalized because they felt unwell, while a ground engineer was knocked off his feet by the force of the blast, but not hurt.
Earlier Tuesday, Chinese authorities ordered China Airlines and its subsidiary Mandarin Airlines to ground their 13 other Boeing 737-800s pending a thorough inspection. Japan's Transport Ministry said they found no problems in all Boeing 737-800 planes owned by Japanese airlines.
The incident has come as a blow to an already rocky safety record at the Taiwanese airline.
A China Airlines 747 crashed in 2002 as it flew from Taipei to Hong Kong, leading to 225 deaths. Some 450 people died in China Airlines accidents during the 1990s.