By Ava Wilhiteawilhite@abcnews4.com
Charleston, S.C. (WCIV) The National Transportation Safety Board's chairman Debbie Hersman said they now know where the fires are starting inside the Boeing 787's lithium ion batteries.
"Based upon findings from the examinations and identifying thermal and mechanical damage, we believe that the evidence points to a single cell as the initiating event," said Hersman.
The NTSB says these batteries are made up of 8 cells. And the problem appears to be in cell number six, which has showed signs of short circuiting in their tests.
"They've isolated it down to a battery, so that's good news for Boeing. Since it's now down to a battery and they are looking at a battery and how they can contain this problem," said Mary Schiavo, airplane attorney.
NTSB Chair Debbie Hersman said their investigation is two fold. One side of the investigation will discover the cause of the battery fire. The other side of the investigation is the review of battery design certification and testing.
"Because the 787 incorporated a number of what the FAA calls novel or unusual design features the applicable air worthiness regulations at the time did not address those new features. So as a result in 2007 the FAA issued nine special conditions for the 787 in regard to the use of lithium ion batteries," said Hersman.
According to Schiavo, Boeing suggested the chance of a fire in those batteries as early as 2007. But Boeing and the Federal Aviation Administration reportedly agreed the risk of fire was low, and approved the design.
"The NTSB wants to know why the FAA approved that in the first place, because allowing a plane to fly with a fire or explosion risk that they know about is quite rare. Usually the government requires you to eliminate that," said Schiavo.
Schiavo said Boeing must now find a better way to contain those batteries.
"Boeing has to change that, that has to be more robust that actually has to do the job and they are talking about putting more separation between the batteries cooling them building a better containment box and that should improve safety," said Schiavo.
The NTSB expects to publish a report in 30 days that is expected to include the cause of the battery fires.