Federal Aviation Administration October 1, 2010 – Federal Register Recent Federal Regulation Documents

We are revising an earlier proposed airworthiness directive (AD) for certain Model 747-100, 747-100B, 747-100B SUD, 747-200B, 747- 200C, 747-200F, 747-300, 747SR, and 747SP series airplanes. The original NPRM would have required adding two new indicator lights on the P10 panel to inform the captain and first officer of a low pressure condition in the left and right override/jettison pumps of the center wing tanks. The original NPRM would also have required replacing the left and right override/jettison switches on the M154 fuel control module on the P4 panel with improved switches and doing the associated wiring changes. The original NPRM would have also required a revision to the maintenance program to incorporate airworthiness limitation No. 28-AWL-22. The original NPRM resulted from fuel system reviews conducted by the manufacturer. This action revises the original NPRM by adding a revision to the airplane flight manual to advise the flightcrew what to do in the event that the pump low pressure light on the flight engineer's panel does not illuminate when the pump is selected off; and requiring, for certain airplanes, installation of a mounting bracket for the new indicator lights. We are proposing this supplemental NPRM to prevent uncommanded operation of the override/ jettison pumps of the center wing tanks, and failure to manually shut off the override/jettison pumps at the correct time, either of which could lead to an ignition source inside the center wing tank. This condition, in combination with flammable fuel vapors, could result in a center fuel tank explosion and consequent loss of the airplane.

We propose to adopt a new airworthiness directive (AD) for all Model MD-90-30 airplanes. This proposed AD would require repetitive high frequency eddy current inspections for cracking on the hinge bearing lugs of the left and right sides of the center section ribs of the horizontal stabilizer, and related investigative and corrective actions if necessary. This proposed AD results from reports of cracks found on either the left or right (or in one case, both) sides of the center section ribs of the horizontal stabilizer. We are proposing this AD to detect and correct cracking in the hinge bearing lugs of the center section of the left and right ribs, which could result in failure of the hinge bearing lugs and consequent inability of the horizontal stabilizer to sustain the required loads.

We propose to adopt a new airworthiness directive (AD) for all Model 45 airplanes. This proposed AD would require a general visual inspection for damage of wiring (including chafing, pinched wires, and exposed wires) and correct routing of wires in the left and right circuit breaker panels, and related investigative and corrective actions if necessary. This proposed AD results from reports of wire damage on the pilot and copilot circuit breaker panels caused by a short circuit between chafed wires. We are proposing this AD to detect and correct damaged or misrouted wires, which could result in a short circuit and the loss of systems associated with the wiring (including fire suppression function for one engine and essential avionics systems).

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.

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: * * * * * Two cases of complete nose landing gear (NLG) shock absorber bolts failure were reported to the manufacturer. In both cases, the crew was unable to retract the gear and was forced to an In Flight Turn Back. In one case, the aircraft experienced a low speed runway excursion. The root cause of the bolts failure has been identified being due to a bolt(s) over-torque. The investigation has highlighted that the design of the NLG shock absorber was not tolerant to the over-torque, and an inspection plan has been developed to track any NLG shock absorber-to-main barrel attachment bolts status. * * * * * * * * We are issuing this AD to require actions to correct the unsafe condition on these products.

We are adopting a new airworthiness directive (AD) for certain Model DC-10-10, DC-10-10F, DC-10-15, DC-10-30, DC-10-30F (KC-10A and KDC-10), DC-10-40, DC-10-40F, MD-10-10F, MD-10-30F, MD-11, and MD-11F airplanes. This AD requires installing an in-line fuse in certain float level switches and sleeving the wires between the fuel tank and the in- line fuse. For certain airplanes, this AD also requires installing an in-line fuse in certain fuel pump pressure switches. This AD results from fuel system reviews conducted by the manufacturer. We are issuing this AD to prevent fuel tank explosions and consequent loss of the airplane.