FAA Grounds 787s

[Machaca]

The NTSB held a press briefing today.

Here's a running synopsis compiled by Leeham News & Comment on Deborah Hersman's (Chair of NTSB) remarks:

• Expectation in aviation is never experience a fire on an aircraft. In two weeks time saw two battery events and groundings.
• Significance of these events can’t be overstated.
• Been working since Jan. 7 to understand what happened and why Lithium ion battery experienced thermal runaway, short circuits and a fire.
• Still trying to find out why.
• 10:49 to 12:15 fire fighters fought the JAL blaze.
• Fire confined to an area within 20 inches on the battery.
• The batteries are unique to the Boeing 787.
• The main battery is the final power source should all other power fail.
• Minor faults found, not unusual following damage. Trying to determine the significance.
• Still trying to gather data.
• Boeing, FAA conducting more activities. NTSB is participating as well.
• Evaluating failure modes, manufacturing records for potential issues or trends, supplier audits.
• Tremendous amount of work going on around the world and around the clock.
• Still trying to analyze failure modes.
• [NTSB will post its PPT presentation on its website later today.]
• [Going through slides right now of components of battery construction]
• Independent examination in DC area for NTSB has been conducted.
• Examining electrodes individually and a number of other methods looking for contaminates or defects.
• We’ve done CT scan of the entire battery.
• We’re looking for signs of thermal runaway (uncontrolled runaway), short circuits, manufacturing defects that could be foreign materials or material defects.
• We have found some short circuits.
• There is bulging present, signs of thermal runaway and short circuiting.
• Still have lab testing on damaged battery and will do testing on an exemplar battery.
• We’ll look at airworthiness, design components, to evaluate the safety of the systems that are integral to the battery.
• FAA and Boeing are parties to investigation, Japan JTSB, GS Yuasa, Japan Airlines, France’s BEA, Thales
• Naval Surface Warfare also assisting; have used lithium ion batteries for decades
• JTSB in Japan is leading investigation on ANA 787 incident.
• Japan ATC did see smoke around ANA aircraft.
• We have to understand why there was a fire when there were so many protections built into the system.
• Not yet determining the cause of the event; just sharing characteristics right now.

Q&A:

• Would not answer a question if the plane would be safe to fly based on information known today. Deferred to FAA’s authority on this.
• It’s very hard to tell how long investigation will take. Working hard to understand failure mode and the solution.
• Grounding is unprecedented and we are very concerned. We don’t expect to see fire on an aircraft.
• We are seeing symptoms right now but have to determine whether these are cause or effect. We need to understand why and how and what came first. Haven’t identified this.
• We are working with JTSB to determine if there is a common cause between JAL and ANA. NTSB is a bit ahead because JAL happened a week earlier, but as yet not enough data to know if there is a common thread.
• Does not answer question if Boeing thought grounding was an over-reaction, again deferring to FAA.
• This JAL airplane had been in the air less than 100 hours and would not expect to see a fire.
• We do not have any data to suggest the battery over-charged beyond design limit.
• Still unsure if there are internal defects to the battery. This is why we are tearing down the batteries.
• It is still open question if this is only the battery or if other components are involved.
• We don’t know if it is possible for one cell to overcharge but the battery overall is not overcharged.
• The ANA event has not been called a fire event, it’s a smoke event.
• We are looking at certification standards, whether they were adhered to and whether they were appropriate. What we have seen in these two events do not comport with any design to protect against the battery events. Those systems did not work as intended. We need to understand why.
• We are still evaluating all failure scenarios.
• [NTSB expert]: damaged cell, short circuits could result in thermal runaway.
• [NTSB chairman]: Testing exemplar batteries and how long it will take: this is interesting technology and are looking for other expertise to assist us. It can take a week to do one of the tests. This is not something we expect to be solved overnight. If we have a breakthrough, and find something that will point to a cause, we’ll get that out. But prepared to be methodical.
• Our investigation will certainly look at the certification process and if we find there are vulnerability we will make recommendations. In past focused on aircraft type but could be global if safety of flight issue.
• We’re looking to see if batteries were from the same batch. Looking at flight data recorders from ANA and JAL events.
• We don’t know if short came first or thermal runaway came first. Have not identified sequence of events. Trying to establish why the events occurred and the sequence.