Federal Aviation Administration November 9, 2007 – Federal Register Recent Federal Regulation Documents

The FAA proposes to supersede an existing airworthiness directive (AD) for PW JT9D-7R4 series turbofan engines. That AD currently requires removing certain reduced cooling flow 2nd stage high pressure turbine (HPT) vane assemblies installed in certain 2nd stage HPT vane cluster assemblies. It also requires a visual and a fluorescent penetrant inspection (FPI) of the 2nd stage HPT air seal assembly, P/N 815097. This proposed AD would require a visual and fluorescent penetrant inspection (FPI) of all part number (P/N) 2nd stage HPT air seal assemblies that were used with reduced cooling flow 2nd stage HPT vane assemblies. This proposed AD results from the manufacturer identifying additional P/N air seal assemblies that are affected by the unsafe condition. We are proposing this AD to prevent uncontained failure of the 2nd stage HPT air seal assembly, leading to engine in-flight shutdown and damage to the airplane.

The FAA proposes to supersede an existing airworthiness directive (AD) that applies to certain Airbus Model A310 series airplanes. The existing AD currently requires modification of certain wires in the right-hand (RH) wing. This proposed AD would require further modification by installing an additional protection sleeve and segregating route 2S in the RH pylon area. This proposed AD results from analysis of wire routing that revealed that route 2S of the fuel electrical circuit, located in the RH wing, does not provide adequate separation of fuel quantity indication wires from wires carrying 115- volt alternating current (AC). We are proposing this AD to ensure that fuel quantity indication wires are properly separated from wires carrying 115-volt AC. Improper separation of such wires, in the event of wire damage, could lead to a short circuit and a possible ignition source, which could result in a fire in the airplane.