787 Inspection Plans Laid Out

Boeing Co. and U.S. regulators joined forces Friday to instruct airlines operating 787 Dreamliners world-wide to inspect, and in some cases possibly replace, emergency-locator transmitters linked to last week's fire inside a parked Ethiopian Airlines 787.

As part of the Federal Aviation Administration's announcement that it will mandate inspections of the devices in coming days, the agency laid out what investigators apparently consider to be the prime suspects behind the blaze that occurred at London Heathrow Airport: Airlines were told to look for "proper wire routing and any sign of wire damage or pinching," referring to the connections between the transmitters, or ELTs, and the lithium batteries that power them. In addition, an FAA statement said inspections should look for unusual signs of heating or moisture inside battery compartments.

Boeing in a statement said it has provided instructions to operators on performing the inspections. It also will issue its own guidance highlighting that 787 operators have the choice of checking the transmitters or voluntarily removing them.

A Boeing spokesman declined to comment on any potential cause of the fire or the ongoing investigation.

The FAA said that over the weekend it plans to communicate its action plan to air-safety regulators in other countries.

FAA officials have told industry representatives the agency could mandate disabling or replacing the transmitters based on inspection results, according to people familiar with the details. Some carriers flying 787s already have checked the devices, and the rest are expected to do so over roughly the next week.

Industry officials said the work isn't expected to disrupt flight schedules.

In an interim report released Thursday, British investigators said the Ethiopian 787's transmitter could have either started the fire or helped spread the flames in the rear of the unoccupied jetliner parked on the tarmac at London Heathrow Airport. The report, however, stopped short of definitely concluding that the device, made by Honeywell International Inc. sparked the fire near the tail, between insulation and the plane's carbon-fiber skin.

But in its brief statement Friday, the FAA provided the most details yet about what investigators apparently suspect could have caused the fire. In addition to wire routing, investigators are looking at whether condensation could have contributed to the problem, according to people familiar with the probe.

Friday's move came amid disparate and sometimes conflicting views of carriers about how to treat the Honeywell devices. Some airlines have been waiting for Boeing to issue guidance or instructions, while others are looking primarily to their own national regulators for help. Still other carriers either already opted to voluntarily remove the emergency transmitters, or decided to keep them in place after inspections disclosed no problems.

European regulators, for their part, are poised to mandate removal of the devices, according to industry officials. But as the agency that certified both the 787 and Honeywell's transmitter, the FAA's statement combined with Boeing's technical guidance could help establish a benchmark for coping with safety issues stemming from the Ethiopian Airlines incident, industry officials said.

Under U.S. rules, airlines can fly passengers on 787s with inoperative or disabled transmitters for as long as 90 days. Other regions follow similar safety standards. In the event of an accident, the roughly six-pound devices, sometimes called emergency beacons, are intended to automatically transmit a signal to help guide emergency crews to the site.

Honeywell has said that over the years it supplied roughly 6,000 of the emergency-transmitter systems, installed on various aircraft built by an array of manufacturers. The company also has said it isn't aware of a single serious thermal event on any of those aircraft.

The FAA on Friday didn't address British recommendations to launch a broad review of lithium-battery-powered emergency transmitters made by various companies and installed on a large number of commercial planes, business jets and general-aviation aircraft built by an array of manufacturers.

Source:   http://online.wsj.com