Federal Aviation Administration September 6, 2012 – Federal Register Recent Federal Regulation Documents

We propose to adopt a new airworthiness directive (AD) for certain Bombardier, Inc. Model BD-100-1A10 (Challenger 300) airplanes. This proposed AD was prompted by reports of failure of a screw cap or end cap of the auxiliary hydraulic system accumulator while on the ground, which resulted in loss of use of that hydraulic system and high-energy impact damage to adjacent systems and structures. This proposed AD would require inspecting for the correct serial number of a certain hydraulic system accumulator, and replacing affected hydraulic system accumulators with new or serviceable accumulators. We are proposing this AD to prevent failure of a screw cap or end cap and loss of the related hydraulic system, which could result in damage to airplane structure and consequent reduced controllability of the airplane.

We propose to supersede an existing airworthiness directive (AD) that applies to certain The Boeing Company Model 747-400 and 747- 400F series airplanes. The existing AD currently requires installing drains and drain tubes to eliminate water accumulation in the dripshield above the M826 cardfile in the main equipment center. Since we issued that AD, we received reports of continued water damage to diode fire card 285U0072-1 in the M826 automatic fire overheat logic test system cardfile following a false FWD CARGO FIRE message, with no change in frequency, which resulted in an air turn back. This proposed AD would instead require installing drain tubes, relocating wire bundle routing, installing a new drip shield and drip shield deflectors, and replacing insulation blankets. For certain airplanes, this proposed AD would also concurrently require sealing the drain slot, installing spuds, and installing drain tubes. We are proposing this AD to prevent water from exiting over the edge of the existing drip shield and contaminating electrical components in the M826 cardfile, which could result in an electrical short and potential loss of several functions essential for safe flight.

We propose to adopt a new airworthiness directive (AD) for certain The Boeing Company Model 737-300, -400, -500, -600, -700, - 700C, -800, -900, and -900ER series airplanes. This proposed AD was prompted by a review of the tail strobe light installation, which revealed that the tail strobe light is not electrically bonded to primary structure of the airplane. This proposed AD would require installing a new tail strobe light housing and a new disconnect bracket, and changing the wire bundles. We are proposing this AD, in case of a direct lightning strike to the tail strobe light, to prevent damage to the operation of other critical airplane systems due to electromagnetic coupling and large transient voltages, and damage to the control mechanisms or surfaces due to a fire, which could result in loss of control of the airplane.

We are adopting a new airworthiness directive (AD) for certain The Boeing Company Model DC-9-10, DC-9-20, DC-9-30, DC-9-40, and DC-9- 50 series airplanes; and Model DC-9-81 (MD-81), DC-9-82 (MD-82), DC-9- 83 (MD-83), DC-9-87 (MD-87), MD-88, and MD-90-30 airplanes; equipped with center wing fuel tank and Boeing original equipment manufacturer- installed auxiliary fuel tanks. This AD was prompted by fuel system reviews conducted by the manufacturer. This AD requires adding design features to detect electrical faults and to detect a pump running in an empty fuel tank. We are issuing this AD to reduce the potential of ignition sources inside fuel tanks, which, in combination with flammable fuel vapors, could result in fuel tank explosions and consequent loss of the airplane.

This action proposes to modify VHF Omnidirectional Range (VOR) Federal airway V-170 between Devils Lake, ND (DVL), and Jamestown, ND (JMS). The FAA is proposing this action to ensure the airway provides the necessary clearance from the western boundary of the newly established restricted area R-5402, Devils Lake, ND, to support non- radar separation requirements when the restricted area is active.

We are adopting a new airworthiness directive (AD) for certain Pratt & Whitney Division PW4000-94'' and PW4000-100'' turbofan engines having a 1st stage high-pressure turbine (HPT) seal support, part number (P/N) 55K601 (contained within assembly P/N 55K602-01) or P/N 50K532 (contained within assembly P/N 50K530-01), installed. This AD was prompted by 58 reports of cracked 1st stage HPT air seal rings, including 15 in-flight engine shutdowns. This AD requires removal and replacement of the 1st stage HPT seal support and inspection of the 1st stage HPT air seal ring. We are issuing this AD to prevent failure of the 1st stage HPT air seal ring, which could lead to an internal oil fire, uncontained engine failure, and damage to the airplane.

The Federal Aviation Administration is requesting public comment on request by the Louisville Regional Airport Authority to change a portion of airport property from aeronautical to non- aeronautical use at the Louisville International Airport, Louisville, Kentucky. The request consists approximately of 1.27 acres of fee simple release. This action is taken under the provisions of Section 125 of the Wendell H. Ford Aviation Investment Reform Act for the 21st Century (AIR 21).

We are adopting a new airworthiness directive (AD) for certain The Boeing Company Model 747-400 series airplanes. This AD was prompted by reports of water leaking into electrical and electronic equipment in the main equipment center (MEC). This AD requires modifying the floor panels; removing drains; installing floor supports, floor drain trough doublers, drain troughs, and drains; and sealing and taping the floor panels. We are issuing this AD to prevent water from entering the MEC, which could result in an electrical short and potential loss of several functions essential for safe flight.

We are adopting a new airworthiness directive (AD) for certain Eurocopter France Model AS350 helicopters. This AD requires installing protection sleeves over certain forward (pitch) servo-control hydraulic hoses. This AD was prompted by an in-flight fire caused by the ignition of hydraulic fluid leaking from a damaged forward servo-control hydraulic hose. This AD's actions are intended to prevent the forward servo-control hydraulic hoses from becoming damaged and leaking hydraulic fluid that could ignite in flight, which could result in loss of main rotor (M/R) control, power loss, structural damage, propagation of fire, and subsequent loss of control of the helicopter.