A damaged battery case from a Japan Airlines Dreamliner sits at the National… (Andrew Harrer, Bloomberg )
After investigating a fire that broke out on Boeing Co.'s 787 Dreamliner passenger jet, the National Transportation Safety Board said that backup protections in the aircraft's lithium-ion batteries and electronics systems failed.
But the safety agency hasn't reached a conclusion on the cause of the fire that occurred in Boston on Jan. 7 and partly led to last week's grounding of Dreamliners worldwide that remains in effect.
Speaking to reporters Thursday from Washington, NTSB Chairwoman Deborah Hersman said the agency hadn't determined what happened, but she added that the redundant safety systems installed by Boeing did not work.
The Federal Aviation Administration grounded the jet Jan. 16 after an emergency landing by All Nippon Airways in Japan because of a second fire believed to involve the plane's onboard lithium-ion batteries. Shortly after the FAA's decision, countries around the world prohibited the new plane from flying.
"These events should not happen," said the safety board's chairwoman. "As far as design of the aircraft, there are multiple systems to protect against a battery event like this. Those systems did not work as intended."
The decision on whether 787s should continue to be grounded in the U.S. belongs to the FAA. The independent safety board is responsible for collecting forensic evidence and conducting tests to determine what happened.
There is no timeline to when tests will be completed, but Hersman said the agency has "all hands on deck" looking into the problem. Investigators around the world are disassembling and scanning the batteries.
In its search for the exact cause of the fires, the NTSB has said it is looking for possible contaminants or manufacturing defects. The agency is also working with officials from Boeing, the FAA and the Navy, as well as investigators in France and Japan.
Japan, where the second fire occurred, is also where Boeing's lithium-ion batteries are made by Kyoto-based GS Yuasa Corp. The Japan Transport Safety Board, the country's version of the FAA, is heading up the investigation into All Nippon's emergency landing and reported fire.
So far, the NTSB's investigators in the Boston fire have found that overheating was caused by short circuits and "thermal runaway," a chain reaction in which heat spreads rapidly from cell to cell, Hersman said. "The significance of these events cannot be understated."
Boeing said in a statement that it is working with its airline customers and the regulatory agencies to get the matter resolved but that it is not permitted to comment directly on the ongoing investigations.
"The company has formed teams consisting of hundreds of engineering and technical experts who are working around the clock with the sole focus of resolving the issue and returning the 787 fleet to flight status," Boeing said. "The safety of passengers and crew members who fly aboard Boeing airplanes is our highest priority."
The 787's battery systems were called into question on Jan. 7 when a smoldering fire was discovered on the underbelly of the plane operated by Japan Airlines after the 183 passengers and 11 crew members had deplaned at the gate.
In the second incident, which involved All Nippon Airways, smoke was seen swirling from the right side of the cockpit after an emergency landing related to the plane's electrical systems. All 137 passengers and crew members were evacuated from the aircraft and slid down the 787's emergency slides. Video of the event was captured by an onboard passenger and has been broadcast worldwide.
No one has been reported hurt or injured. But the recent events have become a public relations nightmare for the Chicago company, which has long heralded the Dreamliner as a representation of 21st century air travel.
Boeing has taken 848 orders for 787s from airlines and aircraft leasing firms around the world. Depending on the version ordered, the price ranges from $206.8 million to $243.6 million per jet.
The company has delivered 50 787s to eight airlines worldwide. Six are owned by Chicago-based United Airlines — the only U.S. carrier that currently has 787s in its fleet.
In an earnings conference call on Thursday, United Continental Holdings Inc. Chief Executive Jeff Smisek defended the plane.
"History teaches us that all new aircraft types have issues, and the 787 is no different," Smisek said. "We continue to have confidence in the aircraft and in Boeing's ability to fix the issues, just as they have done on every other new aircraft model they've produced."
In trading Thursday, Boeing's stock closed up $1.03, or 1.4%, at $75.32. But the stock fell in after-hours trading, at one point dropping 30 cents, or 0.4%, to $75.02.
Problems are expected with any new plane — especially one as complicated and sophisticated as the 787. But the last time the FAA grounded a large commercial jet out of safety concerns was almost 34 years ago after a DC-10 crashed at Chicago O'Hare International Airport, killing all 271 aboard.
The 787, a twin-aisle aircraft that can seat 210 to 290 passengers, is the first large commercial jet with more than half its structure made of composite materials (carbon fibers meshed together with epoxy) rather than aluminum sheets. It's also the first large commercial aircraft that extensively uses electrically powered systems involving lithium-ion batteries.