Japan's two leading airlines grounded their fleets of Boeing 787s today after one of the Dreamliner passenger jets made an emergency landing.
This was the latest and most serious in a series of incidents to heighten safety concerns over a plane many see as the future of commercial aviation.
All Nippon Airways said instruments on a domestic flight indicated a battery error, triggering emergency warnings.
It said the battery in the cargo hold was the same lithium-ion type as one involved in a fire on another Dreamliner in the US last week.
The carrier grounded all 17 of its 787s, and Japan Airlines Co suspended its 787 flights scheduled for today.
ANA said its planes could be back in the air as soon as tomorrow once checks were completed. The two carriers operate around half of the 50 Dreamliners delivered by Boeing to date.
The latest incident, described by a transport ministry official as "highly serious" - language used in international safety circles as indicating there could have been an accident - is the latest in a line of mishaps - fuel leaks, a battery fire, wiring problem, brake computer glitch and cracked cockpit window - to hit the world's first mainly carbon-composite airliner in recent days.
The 787, which has a list price of $207m, represents a leap in the way planes are designed and built, but the project has been plagued by cost overruns and years of delays. Some have suggested Boeing's rush to get planes built after those delays resulted in the recent problems, a charge the company strenuously denies.
Both the US Federal Aviation Administration (FAA) and the National Transportation Safety Board (NTSB) said they were monitoring the latest incident as part of a comprehensive review of the Dreamliner announced late last week.
ANA flight 692 left Yamaguchi Airport in western Japan last night bound for Haneda Airport near Tokyo, a 65-minute flight. About 18 minutes into the flight, at 30,000 feet, the plane began a descent, cutting its altitude to 20,000 feet in about four minutes.
It made an emergency landing 16 minutes later, according to flight-tracking website Flightaware.com. A spokesman for Osaka airport authority said the plane landed at Takamatsu and that all 129 passengers and eight crew evacuated via the plane's inflatable chutes.
At a news conference - where ANA's vice-president Osamu Shinobe bowed deeply in apology - the carrier said a battery in the forward cargo hold triggered emergency warnings to the pilots, who decided on the emergency action.
"There was a battery alert in the cockpit and there was an odd smell detected in the cockpit and cabin, and the pilot decided to make an emergency landing," Shinobe said.
Passengers leaving the ANA flight told local TV there was a smell like burning plastic on the plane as soon as it took off.
A senior safety official at Japan's Civil Aviation Bureau said that an emergency light indicating a malfunction had gone off in the cockpit, followed by another warning light indicating smoke. Checks showed a battery error and smoke was smelled in the cockpit, he added.
In Asia, only the Japanese and Air India have the Dreamliner in service, but other airlines are among those globally to have ordered around 850 of the new aircraft. Australia's Qantas Airways said its order for 15 Dreamliners remained on track, with its Jetstar subsidiary due to take delivery of the first of the aircraft in the second half of this year.
India's aviation regulator said it was reviewing the Dreamliner's safety and would talk to parts makers, but had no plans to ground the six planes operated by state-owned Air India. "We are not having any problem with our Dreamliners. The problems we had earlier were fixed," Arun Mishra, Director General of Civil Aviation, said.
United Airlines, the only US carrier currently flying the 787, said it was not taking any immediate action in response to the latest incident. "We are looking at what is happening with ANA and we will have more information tomorrow," a spokeswoman said.
The Dreamliner's problems echo those of rival Airbus , which a year ago survived a crisis of public confidence after a series of incidents with wing cracks on its A380, the world's largest passenger jet. Those problems tested the manufacturer's relations with airlines, but no plane orders were cancelled.
The use of new battery technology is among the cost-saving features of the 787, which Boeing says burns 20% less fuel than rival jets using older technology. Lithium-ion batteries can catch fire if they are overcharged, and once alight, they are difficult to put out as the chemicals produce oxygen, Boeing's chief engineer for the 787, Mike Sinnett, told reporters last week.
The 787 is Boeing's first new jet in more than a decade, and the company's financial fortunes are largely tied to its success. The plane offers airlines unprecedented fuel economy, but the huge investment to develop it coupled with years of delay in delivery has caused headaches for customers, hurt Boeing financially and created a delivery bottleneck.
