Federal Aviation Administration August 21, 2007 – Federal Register Recent Federal Regulation Documents

The FAA is revising an earlier proposed airworthiness directive (AD) for all Boeing Model 767 airplanes. The original NPRM would have required the following actions for the drive mechanism of the horizontal stabilizer: Repetitive detailed inspections for discrepancies and loose ball bearings; repetitive lubrication of the ballnut and ballscrew; repetitive measurements of the freeplay between the ballnut and the ballscrew; and corrective action if necessary. The original NPRM resulted from a report of extensive corrosion of a ballscrew in the drive mechanism of the horizontal stabilizer on a similar airplane model. This action revises the original NPRM by including additional initial and repetitive inspections of the ballscrew-to-ballnut freeplay for certain airplanes, and adding a new compliance time for those inspections. We are proposing this supplemental NPRM to prevent an undetected failure of the primary load path for the ballscrew in the drive mechanism of the horizontal stabilizer and subsequent wear and failure of the secondary load path, which could lead to loss of control of the horizontal stabilizer and consequent loss of control of the airplane.

We propose to adopt a new airworthiness directive (AD) for certain GARMIN International (GARMIN) GSM 85 servo gearbox units that are installed on airplanes. This proposed AD would require you to inspect the GSM 85 servo gearbox for foreign object debris and return the unit to the manufacturer for replacement if you find debris. This proposed AD results from reports of certain GARMIN GSM 85 servo gearbox units that have foreign object debris inside the assembly. We are proposing this AD to detect and correct defective GARMIN GSM 85 servo gearbox units, which could result in jamming of the gearbox. Jamming of the gearbox could lead to the pilot having to apply excessive manual force to control the airplane.

We are adopting a new airworthiness directive (AD) for the products listed above. This 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:

We are adopting a new airworthiness directive (AD) to supersede 93-07-11 and AD 94-04-16, which apply to certain Mitsubishi Heavy Industries MU-2B series airplanes. AD 93-07-11 and AD 94-04-16 currently require you to reduce the maximum deflection of the elevator nose-down trim to a 1-degree to 3-degree range. When the above AD actions were issued, there was no associated elevator trim indicator change. Without such change, the trim reaches the maximum nose-down limit and the indicator still shows additional nose-down trim available. In attempting to force additional nose-down trim, pilots have manually jammed the trim system preventing subsequent electric trim changes until the pilot manually freed the trim wheel. Consequently, this AD retains the actions from AD 93-07-11 and AD 94- 04-16 and adds the action of modifying the elevator trim indicator scale dial to be consistent with the reduced elevator trim capability. We are issuing this AD to prevent the above scenarios from occurring with consequent loss of control.

We are adopting a new airworthiness directive (AD) for the products listed above. This AD results from mandatory continuing airworthiness information (MCAI) issued 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:

We are adopting a new airworthiness directive (AD) for the products listed above. This AD results from mandatory continuing airworthiness information (MCAI) issued 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:

We are adopting a new airworthiness directive (AD) for the products listed above. This AD results from mandatory continuing airworthiness information (MCAI) issued by the aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI describes the unsafe condition as: