Summary
We propose to adopt a new airworthiness directive (AD) for certain The Boeing Company Model 777F series airplanes. This proposed AD was prompted by a report of a fire that originated near the first officer's seat and caused extensive damage to the flight deck. This proposed AD would require replacing the low-pressure oxygen hoses with non-conductive low-pressure oxygen hoses in the stowage box and supernumerary ceiling area. We are proposing this AD to prevent electrical current from passing through an internal, anti-collapse spring of the low-pressure oxygen hose, which can cause the low- pressure oxygen hose to melt or burn and lead to an oxygen-fed fire on the flight deck.