AD FAA-2012-0489

We are adopting a new airworthiness directive (AD) for all BAE SYSTEMS (Operations) Limited Model 4101 airplanes. This AD was prompted by reports that the fire extinguisher in the toilet vanity unit needs to be mounted vertically rather than horizontally. This AD requires inspecting to determine if a certain fire extinguisher bottle is installed, and repositioning the affected fire extinguisher bottle to the vertical position. We are issuing this AD to detect and correct the orientation of the fire extinguisher bottle in the toilet vanity unit to the vertical position, which if not corrected, could result in a toilet waste bin fire spreading, and consequent damage to the airplane and injury to its occupants.