Federal Aviation Administration September 1, 2005 – Federal Register Recent Federal Regulation Documents

This action corrects errors in certain amendments to the required IFR (instrument flight rules) altitudes and changeover points for certain Federal airways, jet routes, or direct routes for which a minimum or maximum en route authorized IFR altitude is prescribed listed in a final rule published in the Federal Register on August 2, 2005 (70 FR 44278).

The FAA proposes to adopt a new airworthiness directive (AD) for certain EMBRAER Model EMB-135 airplanes, and Model EMB-145, -145ER, -145MR, -145LR, -145XR, -145MP, and -145EP airplanes. This proposed AD would require modification of the upper frame of the firewall for the auxiliary power unit (APU). This proposed AD results from the discovery of a hole in the upper frame of the firewall for the APU. We are proposing this AD to prevent smoke from entering the passenger cabin in the event of a fire in the APU compartment.

The FAA proposes to supersede an existing airworthiness directive (AD) that was issued for General Electric Company (GE) CF34- 3A1 and -3B1 series turbofan engines with certain part numbers (P/Ns) and serial numbers (SNs) of stage 5 low pressure turbine (LPT) disks and stage 6 LPT disks. These engines are installed in Bombardier Canadair CL600-2B19 Regional Jet (RJ) airplanes. This proposed AD would add SNs to the affected disk population for RJ airplanes. This proposed AD would also add GE CF34-1 and -3 series turbofan engines with certain P/Ns and SNs of stage 5 LPT disks and stage 6 LPT disks, to the applicability section. These engines are installed in Bombardier Canadair models CL-600-2A12 (CL-601), CL-600-2B16 (CL-601-3A), (CL-601- 3R), and (CL-604) Business Jet (BJ) airplanes. This proposed AD would require initial and repetitive visual and eddy current inspections (ECI) of the affected disk population. This proposed AD would also allow replacement of those disks as optional terminating action to the repetitive inspections. Also, this proposed AD would require eventual replacement of the affected disks as terminating action to the repetitive inspections. This proposed AD results from the discovery of additional suspect stage 5 LPT disks and stage 6 LPT disks. These disks could fail due to low-cycle fatigue cracking that may start at the site of an electrical arc-out on the disk. We are proposing this AD to prevent low-cycle-fatigue (LCF) failure of stage 5 LPT disks and stage 6 LPT disks, which could lead to uncontained engine failure.

This notice announces the availably of and requests comments on a proposed Advisory Circular (AC) 20-DATABUS, Aviation Databus Assurance. This proposed AC provides guidance for manufacturers of aircraft, aircraft engine, and avionics incorporating databuses and databus technology in the design of their aircraft, aircraft engine, or avionics systems. In the proposed AC, we recommend how you as the manufacturer, may get design and airworthiness approval for your databus.

The Federal Aviation Administration (FAA) announces its findings on the Noise Compatibility Program revision submitted by the city of Austin under the provisions of 49 U.S.C. (the Aviation Safety and Noise Abatement Act, hereinafter referred to as ``the Act'') and 14 CFR part 150. These findings are made in recognition of the description of Federal and nonfederal responsibilities in Senate Report No. 96-52 (1980). On April 5 and May 8, 2000, The FAA determined that the noise exposure maps submitted by the city of Austin under part 150 complied with applicable requirements. On August 5, 2005, the FAA approved a revision to the Austin-Bergstrom International Airport Noise Compatibility Program. The program measure in this revision was fully approved.

The FAA is superseding an existing airworthiness directive (AD), which applies to certain Bombardier Model CL-215-1A10 and CL-215- 6B11 series airplanes. That AD currently requires repetitive ultrasonic inspections to detect cracking of the lower caps of the wing front spar and rear spar, and corrective action if necessary. This new AD reduces the threshold to do the initial inspections and revises the repetitive inspection interval. This new AD also adds a repetitive ultrasonic inspection of the wing lower skin. This AD results from reports of cracks in the front and rear spar lower caps. We are issuing this AD to detect and correct cracking of the lower caps of the wing front spar and rear spar, which could result in reduced structural integrity of the airplane.

The FAA is superseding an existing airworthiness directive (AD) for Pratt & Whitney (PW) PW2000 series turbofan engines. That AD currently requires revisions to the engine manufacturer's time limits section (TLS) to include enhanced inspection of selected critical life- limited parts at each piece-part opportunity. This AD requires modifying the airworthiness limitations section of the manufacturer's manual and an air carrier's approved continuous airworthiness maintenance program to incorporate additional inspection requirements. This AD results from an FAA study of in-service events involving uncontained failures of critical rotating engine parts that indicates the need for mandatory inspections. The mandatory inspections are needed to identify those critical rotating parts with conditions, which if allowed to continue in service, could result in uncontained failures. We are issuing this AD to prevent critical life-limited rotating engine part failure, which could result in an uncontained engine failure and damage to the airplane.

This action amends Title 14 Code of Federal Regulations (14 CFR) part 71 relating to airspace designations to reflect the approval by the Director of the Federal Register of the incorporation by reference of FAA Order 7400.9N, Airspace Designations and Reporting Points. This action also explains the procedures the FAA will use to amend the listings of Class A, B, C, D, and E airspace areas; air traffic service routes; and reporting points incorporated by reference.