Federal Aviation Administration December 21, 2009 – Federal Register Recent Federal Regulation Documents

This action proposes to modify Class E airspace at Yellowstone Airport, West Yellowstone, MT, to accommodate aircraft using a new Area Navigation (RNAV) Global Positioning System (GPS) Standard Instrument Approach Procedure (SIAP) at Yellowstone Airport, West Yellowstone, MT. The FAA is proposing this action to enhance the safety and management of instrument flight rules (IFR) operations at the airport.

The FAA proposes to revise an existing airworthiness directive (AD) for Pratt & Whitney JT8D-209, -217, -217C, and -219 turbofan engines with front compressor front hub (fan hub), part number (P/N) 5000501-01 installed. That AD currently requires cleaning the front compressor front hubs (fan hubs), initial and repetitive eddy current (ECI) and fluorescent penetrant inspections (FPI) of tierod and counterweight holes for cracks, removal of bushings, cleaning and ECI and FPI of bushed holes for cracks and, if necessary, replacement with serviceable parts. In addition, that AD currently requires reporting the findings of cracked fan hubs and monthly reports of the number of inspections completed. This proposed AD would require the same actions, except for the monthly reporting of the number of completed inspections. This proposed AD results from the FAA determining that it has collected a sufficient amount of data since issuing AD 97-17-04 and that therefore, it no longer needs the monthly reporting of the number of completed inspections. We are proposing this AD revision to prevent fan hub failure due to tierod, counterweight, or bushed hole cracking, which could result in an uncontained engine failure and damage to the airplane.

The FAA proposes to supersede an existing airworthiness directive (AD) for CFM International, S.A. CFM56-5B series turbofan engines. That AD currently requires reviewing exhaust gas temperature (EGT) monitoring records to determine EGT margin deterioration, and for airplanes where both engines have greater than 80 [deg]centigrade (C) of EGT margin deterioration, borescope-inspecting the high-pressure compressor (HPC) of both engines. That AD also currently requires removing from service any engine that does not pass the borescope inspection and, if both engines pass, removing and replacing one of the engines with an engine that has 80 [deg]C or less of EGT margin deterioration. That AD also currently requires continuous monitoring of EGT margin deterioration on engines in service to prevent two engines on an airplane from having greater than 80 [deg]C of EGT margin deterioration. This proposed AD would require continuous monitoring of EGT margin deterioration, removing FADEC software version 5.B.Q and earlier versions from the engine as mandatory terminating action to the repetitive recalculating and EGT monitoring for certain engine models, and removing other certain engine models from service if the EGT margin deterioration is greater than 75 [deg]C. This proposed AD results from the need to reduce the affected engine models listed in AD 2009-01-01 from 25 to 19, the need to reduce the engine EGT margin deterioration removal threshold from greater than 80 [deg]C to greater than 75 [deg]C, the need to mandate a terminating action to the repetitive recalculating and EGT monitoring for certain engines, and the need to remove certain engines from service if the EGT margin deterioration is greater than 75 [deg]C. We are proposing this AD to prevent HPC stalls, which could prevent continued safe flight or landing.

This notice contains a summary of a petition seeking relief from specified requirements of 14 CFR. The purpose of this notice is to improve the public's awareness of, and participation in, this aspect of FAA's regulatory activities. Neither publication of this notice nor the inclusion or omission of information in the summary is intended to affect the legal status of the petition or its final disposition.

The FAA is issuing this notice to advise the public that a meeting of the Federal Aviation Administration Air Traffic Procedures Advisory Committee (ATPAC) will be held to review present air traffic control procedures and practices for standardization, revision, clarification, and upgrading of terminology and procedures.