Boeing 787 operators have been advised to look for "pinched wiring" and evidence of moisture during their soon-to-be-mandated inspections of the emergency locator transmitter (ELT) and surrounding equipment.
The recommendation was made by the US Federal Aviation Administration following initial investigation of the 12 July Ethiopian Airlines Dreamliner fire, which occurred in the rear cabin ceiling area where the ELT is positioned.
Having reviewed the initial findings of the UK Air Accidents Investigation Branch, the FAA says it is "working with Boeing to develop instructions to operators for inspection of the ELTs on 787 aircraft".
"These inspections would ask operators to inspect for proper wire routing and any signs of wire damage or pinching, as well as inspect the battery compartment for unusual signs of heating or moisture," it adds.
An airworthiness directive is to be issued "in the coming days", adds the FAA, which notes: "Federal Aviation Regulations do not require large commercial aircraft in scheduled service to be equipped with these devices."
Other aviation authorities will be informed of the FAA's intentions: "As an active participant in the AAIB's investigation, we continue to work closely with the AAIB, along with Boeing and Honeywell [the ELT manufacturer] as the investigation continues."