Federal Aviation Administration February 26, 2007 – Federal Register Recent Federal Regulation Documents

The FAA is superseding an existing airworthiness directive (AD) for Pratt & Whitney PW4077D, PW4084D, PW4090, and PW4090-3 turbofan engines that were reassembled with previously used high pressure compressor (HPC) exit brush seal packs and new or refurbished HPC exit diffuser air seal lands. That AD currently requires replacing the HPC exit inner and outer brush seal packs with new brush seal packs, or replacing the HPC exit brush seal assembly with a new HPC exit brush seal assembly. This AD requires replacing the HPC exit inner and outer brush seal packs with new brush seal packs, using either original equipment manufactured (OEM) parts, or FAA-approved part manufacturer approval (PMA) parts. This proposed AD also applies to engines reassembled with a PMA HPC exit inner and or outer brush seal packs. This AD results from a request to include PMA HPC exit inner and outer brush seal packs and to include the engines with PMA parts already installed, in the AD. We are issuing this AD to prevent uncontained engine failure, damage to the airplane, and injury to passengers.

This notice proposes to amend Class E5 airspace at Middlesboro, KY. An Area Navigation (RNAV) Global Positioning System (GPS) Standard Instrument Approach Procedure (SIAP) A has been developed for Middlesboro-Bell County Airport. As a result, additional controlled airspace extending upward from 700 feet Above Ground Level (AGL) is needed to contain the SIAP.

This rule establishes a Class E airspace area extending upward from 700 feet above the surface at Potosi, MO. The effect of this rule is to provide appropriate controlled Class E airspace for aircraft departing from and executing instrument approach procedures to Potosi Washington County Airport, MO and to segregate aircraft using instrument approach procedures in instrument conditions from aircraft operating in visual conditions.

These special conditions are issued for Raytheon Aircraft Company Model BAe.125 Series 800A airplanes modified by Duncan Aviation Inc. These modified airplanes will have novel or unusual design features when compared to the state of technology envisioned in the airworthiness standards for transport category airplanes. The modification incorporates the installation of electronic flight and engine instrument systems. The applicable airworthiness regulations do not contain adequate or appropriate safety standards for protecting these systems from the effects of high-intensity radiated fields (HIRF). These special conditions contain the additional safety standards the Administrator considers necessary to establish a level of safety equivalent to that established by the existing airworthiness standards.

The FAA proposes to adopt a new airworthiness directive (AD) for certain McDonnell Douglas Model DC-10-30 and DC-10-30F (KC-10A and KDC-10) airplanes, Model DC-10-40 and DC-10-40F airplanes, and Model MD-10-30F airplanes. This proposed AD would require installing bracket assemblies and jumper wires in the center main wheel well to improve the bonding path between the structure (wall) of the lower auxiliary fuel tank and its internal fuel pumps; measuring the electrical resistance between the fuel pump housings and the fuel tank structure; and doing corrective actions if necessary. This proposed AD results from fuel system reviews conducted by the manufacturer. We are proposing this AD to detect and correct an inadequate bond between the internal fuel pump housings and the structure of the lower auxiliary fuel tank. This condition, if not corrected, could fail to meet fault current requirements and result in a potential ignition source that, in combination with flammable fuel vapors, could cause a fuel tank explosion and consequent loss of the airplane.

The FAA proposes to adopt a new airworthiness directive (AD) for all McDonnell Douglas Model MD-11 and MD-11F airplanes. This proposed AD would require installing bracket assemblies and jumper wires in the center main wheel well to improve the bonding path between the structure (wall) of the lower auxiliary fuel tank and its internal fuel pumps; measuring the electrical resistance between the fuel pump housings and the fuel tank structure; and doing corrective actions if necessary. This proposed AD results from fuel system reviews conducted by the manufacturer. We are proposing this AD to detect and correct an inadequate bond between the internal fuel pump housings and the structure of the lower auxiliary fuel tank. This condition, if not corrected, could fail to meet fault current requirements and result in a potential ignition source that, in combination with flammable fuel vapors, could cause a fuel tank explosion and consequent loss of the airplane.

The FAA proposes to adopt a new airworthiness directive (AD) for certain McDonnell Douglas airplanes described previously. This proposed AD would require installing bonding jumpers to the airplane wing structure from the fuel system in-line electrical solenoid valves along the left and right wing front spar. This proposed AD results from fuel system reviews conducted by the manufacturer. We are proposing this AD to prevent point-of-contact arcing or filament heating damage in the fuel lines that could create a potential ignition source, which, in combination with flammable fuel vapors, could cause a fuel tank explosion and consequent loss of the airplane.