Following a fire aboard an Ethiopian Airlines 787 at Heathrow Airport, British investigators today recommended removing an emergency beacon manufactured by Honeywell on all Boeing 787s while a safety review of the devices in other planes is conducted.
The Air Accidents Investigation Branch the (UK's version of the NTSB) said the Honeywell Emergency Locator Transmitter (ELT) "has shown some indications of disruption to the battery cells."
"It is not clear however, whether the combustion in the area of the ELT was initiated by a release of energy within the batteries or by an external mechanism such as an electrical short," the AAIB report stated. "In the case of an electrical short, the same batteries could provide the energy for an ignition and suffer damage in the subsequent fire."
In a statement, Boeing said, "As a party to the investigation, Boeing supports the two recommendations from the UK Air Accidents Investigation Branch (AAIB), which we think are reasonable precautionary measures to take as the investigation proceeds," the company said. "We are working proactively to support the regulatory authorities in taking appropriate action in response to these recommendations, in coordination with our customers, suppliers, and other commercial airplane manufacturers. We are confident the 787 is safe and we stand behind its overall integrity."
The company said, "The safety of passengers and crew members who fly aboard Boeing airplanes is our highest priority." The Dreamliner is Boeing's newest and most fuel-efficient aircraft, with orders for more than 500 planes on the books.
Honeywell, the maker of the aviation emergency transmitters, said it "supports the AAIB's proposal and will offer assistance to Boeing and the airlines if needed."
"The investigation continues, and it's premature to jump to conclusions," according to a statement from the company. "Temporarily addressing the ELTs on Boeing 787s as a precautionary measure is prudent. The Boeing 787 ELT product action is a straightforward process, and we do not anticipate any material financial impact to Honeywell. We also support conducting safety reviews for installations of any lithium battery-powered ELTs from the variety of manufacturers who sell them."
In response to the AAIB's report, the Federal Aviation Administration said in a statement, "We are currently reviewing the AAIB's report and recommendations to determine the appropriate action. We will work closely with the AAIB, as well as Boeing and Honeywell, as the investigation into the cause continues."
The 787 was on a remote parking stand last Friday when the fire occured and there were no passengers on board. The airport was closed to air traffic during the incident.
Boeing shares rebounded on the news that seems to clear the company of blame. Daniel Holland, equity analyst with Morningstar, said, "The fact that no airline has planned to stop flying the 787 likely means the initial drop was somewhat unwarranted, and it seems as though investors are buying the stock back to previous levels. In general, I think investors are playing the strong aerospace cycle that includes manufacturers and the supply chain."
About 6,000 units of this design of the ELT, "which are fitted to a wide range of aircraft and, to date, the incident on 12 July 2013 has been the only significant thermal event," the AAIB said.
On Saturday, the AAIB said the incident was most likely not related to a battery issue that grounded 787 planes earlier this year.
Until mid-April, the Federal Aviation Administration and other regulators grounded the global Dreamliner fleet for three months due to a battery catching fire on a plane parked in Boston, and another emergency landing in Japan. The batteries and their cases were redesigned as a result of the grounding.