Japan's two leading airlines have grounded their fleets of Boeing 787s after one of the Dreamliner passenger jets made an emergency landing, 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 aboard a domestic flight indicated a battery error, triggering emergency warnings to the pilots. It said the battery in the forward cargo hold was the same lithium-ion type as one involved in a fire on another Dreamliner at a United States airport last week.
The carrier grounded all 17 of its 787s, and Japan Airlines suspended its 787 flights scheduled for Wednesday. ANA said its planes could be back in the air as soon as Thursday once checks were completed. The two carriers operate around half of the 50 Dreamliners delivered by Boeing to date.
Wednesday's 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.
"I think you're nearing the tipping point where they need to regard this as a serious crisis," said Richard Aboulafia, a senior analyst with the Teal Group in the US. "This is going to change people's perception of the aircraft if they don't act quickly."
The 787, which has a list price of US$207 million (NZ$246 million), 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 shortly after 8am local time (noon NZT) bound for Haneda Airport near Tokyo, a 65-minute flight. About 18 minutes into the flight, at 9000 metres, the plane began a descent, cutting its altitude to 6000 metres 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 at 8.45am All 129 passengers and eight crew evacuated via the plane's inflatable chutes. Chief Cabinet Secretary Yoshihide Suga said five people were slightly injured.
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 an odour like burning plastic on the plane as soon as it took off. "There was a bad smell as soon as we started and before we made the emergency landing there was an announcement and the stewardess' voice was shaking, so I thought this was serious," one passenger told TBS TV.
Shigeru Takano, a senior safety official at the 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.
One man told a local broadcaster there was a burning smell in the plane. "There was a strong, burning smell, but the smoke appeared after they opened the emergency doors, after we landed," he said.
Marc Birtel, a Boeing spokesman, told Reuters: "We've seen the reports, we're aware of the events and are working with our customer."
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.
Air New Zealand is to start flying a larger variant of the Dreamliner, known as the 787-9, next year, Radio New Zealand reported.
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, told Reuters.
United Airlines, the only U.S. 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.