Federal Aviation Administration April 8, 2010 – Federal Register Recent Federal Regulation Documents

This action proposes to revise Class E airspace at Galena, AK. The amendment of three Standard Instrument Approach Procedures (SIAPs), and the development of one Obstacle Departure Procedure (ODP) at the Edward G. Pitka Sr. Airport have made this action necessary to enhance safety and management of Instrument Flight Rules (IFR) operations.

We propose to adopt a new airworthiness directive (AD) for the products listed above. This proposed AD results from mandatory continuing airworthiness information (MCAI) originated by an aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI describes the unsafe condition as: Following five reported cases of balance washer screw failure on similar ADGs [air-driven generators]/ram air turbines installed on other aircraft types, investigation by Hamilton Sundstrand determined that a specific batch of the screws had a metallographic non-conformity that increased their susceptibility to brittle fracture. Failure of a balance washer screw can result in loss of the related balance washer, with consequent turbine imbalance. Such imbalance could potentially result in ADG structural failure (including blade failure), loss of ADG electrical power and structural damage to the aircraft and, if deployment was activated by a dual engine shutdown, could also result in loss of hydraulic power for the flight controls [and consequent reduced ability of the flightcrew to maintain the safe flight and landing of the airplane].

We propose to adopt a new airworthiness directive (AD) for certain Model 767 airplanes. This proposed AD would require doing a detailed inspection for correct main track downstop assembly, thread protrusion, and damaged and missing parts of the main track downstop assemblies of the outboard slats, and related investigative and corrective actions if necessary. This proposed AD would also require doing a detailed inspection for foreign objects debris and damage to the wall of the track housing of the outboard slats, and corrective actions if necessary. This proposed AD results from reports of broken bolts in the outboard slat main track downstop assembly. We are proposing this AD to detect and correct incorrectly installed main track downstop assemblies, which can allow the main track downstop hardware to fall into the track housing and cause a puncture in the track housing when the slat is retracted. This condition, if not corrected, could result in a fuel leak and an increased risk of fire.

The FAA proposes to supersede an existing airworthiness directive (AD) that applies to all Model 750 airplanes. The existing AD currently requires inspecting the inboard-hinge brackets of the left and right elevators for cracking and doing related investigative and corrective actions if necessary. For certain airplanes, this proposed AD would require inspecting for cracks and corrosion of the bracket of the inboard horizontal stabilizer and measuring the lug thickness of the horizontal stabilizer hinges; doing corrective actions if necessary; modifying the left and right elevators and left and right horizontal stabilizer. For all airplanes, this proposed AD would require replacing the existing elevator assemblies with new elevator assemblies, which would terminate the requirements of the existing AD. This proposed AD would also revise the applicability to remove certain airplanes. This proposed AD results from a report of cracking and corrosion found on the elevator inboard-hinge brackets and the horizontal stabilizer hinges. We are issuing this AD to prevent such cracking and corrosion of the elevator inboard-hinge brackets and the horizontal stabilizer hinges, which could result in structural failure of the elevators and consequent loss of control of the airplane.

This action corrects the final rule published in the Federal Register December 29, 2009, amending Class E airspace in the Altus, OK area. The geographic coordinates were incorrect for the Altus Localizer. This action corrects that error.