On a January morning in 2013, Kenichi Kawamura was taking the same flight he took every month, from Yamaguchi in southern Japan to the capital, Tokyo.
Everything about the business trip was routine, except that Kawamura was flying on a new Boeing 787 "Dreamliner".
"I felt a little thrilled as I got on board," he says. "It was so new that it still had that new smell."
All Nippon Airways (ANA) Flight 692 took off on time, and after reaching cruising altitude the pilot turned off the fasten seatbelt sign.
'Smoke coming from the fuselage'
Suddenly the plane took a steep dive. "The drink that I'd put on the pull-down table started to slide forwards," says Kawamura. "The three newspapers that I'd put on the seat next to me fell onto the floor."
"I called over a cabin attendant and was about to ask what was going on when there was an announcement from the pilot. His precise words were: 'There is smoke coming from the fuselage but there are no problems with the instrument panel. We will be making an emergency landing in Takamatsu Airport.'"
Passengers became concerned. "I thought we were going to crash. It was fear," says Kawamura.
The plane made its emergency landing safely. But 129 passengers and eight crew members still had to evacuate.
'An incident like no other'
"I was the first person to go down the chute," says Aoye Kazunori, another passenger. "Everyone was so nervous. I was given a push in the back and I left the plane."
Paramedics and firefighters were waiting. Three people were hurt as they slid down the emergency chutes to the tarmac.
"It was an incident like no other, so I remember being really nervous," says Takamatsu firefighter Amitani Noriyuki. After the passengers were taken to safety, investigators turned their attention to what had gone wrong.
"We got a cherry picker alongside the aircraft to look inside the cockpit," says Takamatsu fire investigator Takeuchi Koji. "On closer inspection, we observed a blue box that had expanded in size." It was the 787's battery.
For the second time in service, Boeing's lithium-ion power unit, built especially for the "Dreamliner", had failed.
We chose the lithium-ion battery because it was superior in performance to other battery technology at the time. We were looking for power density.
Another battery had burnt nine days earlier on a 787 owned by Japan Airlines.
Flight JA008 had landed in Boston from Narita when maintenance staff noticed the "auxiliary power unit" (APU) had shut down. A mechanic opened the electronics bay and "found smoke and flames coming from the APU battery", according to the fire report. One firefighter suffered minor injuries.
The regulator, the Federal Aviation Administration (FAA), immediately announced a review of the 787's "critical systems", while also declaring, "this is a safe aircraft". But when the second battery failure happened in Japan, the FAA went further. It grounded all 787s in service in the US.
Regulators and airlines around the world followed the FAA's lead.
Boeing scrambled to find a solution and eventually, without announcing the root cause of the failures, it came up with a fix. The company encased the battery in a heavy steel box and built in more insulation and an exhaust pipe for fumes.
The FAA approved the redesign, and the "Dreamliner" was back in the air by the end of April.
Boeing dreamed big with the 787. Harry Stonecipher, then president and CEO, promised it would be "the biggest game-changer in civil aviation since the 707 at the dawn of the jet age".
Engineers designed many parts to be radically different. For example, the 787 would rely much more on electricity. But to do so, the plane needed a more powerful battery.
Boeing chose the design that it says best met the needs of the 787, including all federal and international safety standards. "We chose the lithium-ion battery because it was superior in performance to other battery technology at the time," Boeing 787 Chief Engineer Mike Sinnett told accident investigators. "We were looking for power density," he said.
The company had chosen one of the most volatile chemistries available, lithium-cobalt. The battery produced nearly 10 times the current of its nickel-cadmium equivalent on the Boeing 777.
'Like a jet afterburner'
But with power density came new risks, as Boeing would find out on the morning of November 7, 2006 in Tucson, Arizona.
That day, a prototype lithium-ion battery for use on the "Dreamliner" failed in testing.
"All of a sudden I was lying on the floor," says Michael Leon, the technician who had been handling the battery. He described seeing a jet of fumes four metres long.
"It looked like a jet afterburner," he says. "The other engineers told me that if I was still in the way, that would have cut me in half like a Jedi light sabre."
The fire destroyed the main factory of Securaplane, the company Boeing had contracted to create a charger for that lithium-ion battery.
Second testing failure
Boeing redesigned the battery after the Securaplane fire, and "added an additional level of protection", according to the FAA.
But three years later, the new design failed at a testing facility in Illinois. Boeing made more changes.
The FAA said Boeing's design must "preclude the occurrence of self-sustaining, uncontrolled increases in temperature or pressure". The special condition for lithium-ion batteries for the 787 was identical to the requirements for other airplanes.
But by January 2013, after two in-service battery failures, it was an open question whether Boeing had met that rule.
Boeing said it had. The US accident investigator, the National Transportation Safety Board (NTSB), said its preliminary findings of the Boston incident were that one of the eight battery cells had demonstrated a "self-sustaining, uncontrolled increase in temperature".
Not enough testing
After the two battery failures, the NTSB began to ask if Boeing had done enough testing. During a two-day hearing in April 2013 to investigate the Boston fire, Boeing appeared to concede it had not.
One of the key tests it did involved hammering a nail into the battery to induce a short circuit. It sounds simplistic, although Boeing said at the time its battery was based on "state of the art" testing.
"In retrospect, I believe we don't feel that [the nail penetation test] was conservative enough," said Boeing's Mike Sinnett at the hearing.
It also emerged that Boeing had not tested in line with industry guidelines, produced by the Radio Technical Commission for Aeronautics (RTCA) and known as DO311.
The code came out three months after Boeing had certified its battery. Even though Boeing was on the board that drew it up, the company said it did not see a need to apply DO311 to the 787 battery.
By May 2014, the NTSB concluded that Boeing had fallen short. Chairman Christopher Hart issued recommendations to the FAA urging them to demand tougher testing of batteries by plane manufacturers like Boeing.
"Boeing was obligated, in my opinion, to have done everything they could to know this was never going to happen," says Richard Lukso, the man who founded Securaplane. He left the company just before the fire of November 2006.
"More testing should have been done," he says.
He says outsourcing is partially to blame. For the "Dreamliner", Boeing contracted the work to a French company called Thales, which in turn outsourced the design and build of the battery to a Japanese company called GS Yuasa. Thales chose Securaplane to make the charger. A third company called Kanto made the battery-monitoring unit.
Lukso says such a complicated supply chain impaired Boeing's oversight. So what are the implications for safety?
"It's directly relative, directly relative to the amount of time you're not there personally," says Lukso. "They don't want to increase the kind of policing they have to do. And as a result, I think a lot of stuff slips through the cracks."
Boeing's bad dream
Today, Boeing says it is confident in the enhanced battery system on the 787. The battery redesigned in 2013 now includes what Boeing describes as "improvements in production, design improvements to battery itself, changes to the battery charger and finally the encasement and exhaust structure, which ensures that any battery cell venting will not affect the airplane".
Boeing has had a nightmare with its lithium-ion battery on the "Dreamliner". The list of problems is long.
A prototype was the source of a fire that destroyed a supplier's factory in 2006. Three years later, another failed in testing. Two batteries burnt up in service in January 2013. Later, it emerged that at least 100 bateries had failed and been sent back to the manufacturer, GS Yuasa in Japan.
That was before the grounding. Afterwards, even with the modifications, there have been issues.
On June 2 last year, Japanese carrier ANA found a problem with a sensor on a modified battery, on a 787 that had only gone back into service a week earlier. In November, JAL reported problems with a battery on a Helsinki-to-Tokyo flight, and ANA announced it had replaced a battery charger. In January 2014, JAL grounded one its "Dreamliners" after white smoke was seen coming from the battery system during a check ahead of take-off.
Whether or not Boeing did enough testing, one thing is clear: The battery came with certain risks that the company may not have fully anticipated.
The benefits of extra electrical power came at the cost of fires, failures and the grounding of an entire fleet.
Read Boeing's full responses
Follow Will Jordan on Twitter: @WillJordan
Source: Al Jazeera