AD FAA-2009-0915

We are adopting a new airworthiness directive (AD) for certain AVOX Systems and B/E Aerospace oxygen cylinder assemblies, as installed on various transport airplanes. This AD requires removing certain oxygen cylinder assemblies from the airplane. This AD was prompted by the reported rupture of a high-pressure gaseous oxygen cylinder, which had insufficient strength characteristics due to improper heat treatment. We are issuing this AD to prevent an oxygen cylinder from rupturing, which, depending on the location, could result in structural damage and rapid decompression of the airplane, damage to adjacent essential flight equipment, deprivation of the necessary oxygen supply for the flightcrew, and injury to cabin occupants or maintenance or other support personnel.