Federal Aviation Administration October 24, 2007 – Federal Register Recent Federal Regulation Documents

We propose to adopt a new airworthiness directive (AD) for certain Cessna Aircraft Company (Cessna) Models 172R and 172S. This proposed AD would require you to inspect the fuel return line assembly for chafing; replace the fuel return line assembly if chafing is found; and inspect the clearance between the fuel return line assembly and both the right steering tube assembly and the airplane structure, adjusting as necessary. This proposed AD results from reports of chafed fuel return line assemblies, which were caused by the fuel return line assembly rubbing against the right steering tube assembly during full rudder pedal actuation. We are proposing this AD to detect and correct chafing of the fuel return line assembly, which could result in fuel leaking under the floor and fuel vapors entering the cabin. This condition could lead to fire under the floor or in the cabin area.

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) 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:

The FAA is adopting a new airworthiness directive (AD) for GE CF6-80C2D1F turbofan engines, installed on, but not limited to, McDonnell Douglas Corporation MD-11 series airplanes. This AD requires removing previous software versions from the engine electronic control unit (ECU). Engines with new version software will have increased margin to flameout. This AD results from reports of engine flameout events during flight, including reports of events where all engines simultaneously experienced a flameout or other adverse operation. Although the root cause investigation is not yet complete, we believe that exposure to ice crystals during flight is associated with these flameout events. We are issuing this AD to minimize engine flameout caused by ice accretion and shedding during flight.

The FAA is adopting a new airworthiness directive (AD) for certain McDonnell Douglas airplanes, identified above. This AD requires a one-time inspection to determine the configuration of the airplane. This AD also requires repetitive inspections for cracking of the tee or angle doubler, and corrective actions if necessary. This AD results from a report indicating that numerous operators have found cracks on the tee. We are issuing this AD to detect and correct stress corrosion cracking of the tee or angle doubler installed on the flat aft pressure bulkhead. Cracking in this area could continue to progress and damage the adjacent structure, which could result in loss of structural integrity of the airplane.