Federal Aviation Administration July 19, 2006 – Federal Register Recent Federal Regulation Documents

The FAA proposes to supersede an existing airworthiness directive (AD) that applies to all Airbus Model A330, A340-200, and A340-300 series airplanes. The existing AD currently requires repetitive inspections of a certain bracket that attaches the flight deck instrument panel to the airplane structure; replacement of the bracket with a new, improved bracket; and related investigative and corrective actions if necessary. This proposed AD would add a requirement for replacement of the existing bracket with a titanium- reinforced bracket, which would end the repetitive inspections in the existing AD. This proposed AD would also require related investigative and corrective actions while accomplishing the replacement, and would reduce the applicability in the existing AD. This proposed AD results from a report of cracking damage found on certain brackets that were replaced per the requirements in the existing AD. We are proposing this AD to prevent a cracked bracket. Failure of this bracket, combined with failure of the horizontal beam, could result in collapse of the left part of the flight deck instrument panel, and consequent reduced controllability of the airplane.

The FAA proposes to adopt a new airworthiness directive (AD) for all BAE Systems (Operations) Limited Model BAe 146 and Avro 146-RJ airplanes equipped with certain hydraulic accumulators. This proposed AD would require inspecting the hydraulic accumulators to identify certain serial numbers, and replacing any affected accumulator with a new or serviceable accumulator. Operators may delay doing the replacement by doing repetitive inspections of the affected hydraulic accumulators for signs of failure (leaking or cracking), and replacing any failed accumulator with a new or serviceable unit. This proposed AD results from a report that one hydraulic accumulator failed in service, which caused the loss of the yellow hydraulic system when the airplane was configured for landing. We are proposing this AD to prevent damage to the pressure skin, failure of certain hydraulic systems, contamination of the cabin with hydraulic mist, increased workload for the flightcrew associated with the loss of one or more hydraulic circuits, and consequent reduced controllability of the airplane.

We are adopting a new airworthiness directive (AD) that supersedes AD 2003-13-04, which applies to certain Pilatus Aircraft Ltd (Pilatus) Model PC-6 airplanes. AD 2003-13-04 currently requires you to inspect the integral fuel tank wing ribs for cracks and the top and bottom wing skins for distortion, repair any cracks or distortion before further flight, and do a fuel tank ventilating system installation. Since we issued AD 2003-13-04, the FAA determined the action should also apply to all the models of the PC-6 airplanes listed in the type certificate data sheet of Type Certificate (TC) No. 7A15 that were produced in the United States through a licensing agreement between Pilatus and Fairchild Republic Company (also identified as Fairchild Industries, Fairchild Heli Porter, or Fairchild-Hiller Corporation). In addition, the intent of the applicability of AD 2003- 13-04 was to apply to all the affected serial numbers of the airplane models listed in TC No. 7A15. This AD retains all the actions of AD 2003-13-04, adds those Fairchild Republic Company airplanes to the applicability of this AD, and lists the individual specific airplane models. We are issuing this AD to detect and correct cracks in the ribs of the inboard integral fuel tanks in the left and right wings, which could lead to wing failure during flight with consequent loss of control of the airplane.