Federal Aviation Administration August 21, 2012 – Federal Register Recent Federal Regulation Documents

The FAA is issuing a SNPRM for the notice of proposed rulemaking (NPRM) of June 4, 2012, in order to elicit comments addressing increasing further the controlled Class E airspace area at Lewiston-Nez Perce County Airport, Lewiston, ID. The NPRM proposed a modification of Class D airspace, and Class E airspace extending upward from 700 feet above the surface and 1,200 feet above the surface, and an adjustment to the geographic coordinates. This SNPRM would further enlarge the Class E airspace 1,200 feet above the surface area to enhance safety in the Lewiston-Nez Pearce County Airport, Lewiston, ID area.

We propose to adopt a new airworthiness directive (AD) for certain The Boeing Company Model 737-100, -200, -200C, -300, -400, and -500 series airplanes. This proposed AD was prompted by a report of an approximate 8-inch crack found in the fuselage skin under the aft drain mast. This proposed AD would require a detailed inspection for cracking and corrosion of the channel and fillers adjacent to the drain mast bolts, an inspection to determine the location of the bonding strap, a measurement of the washers under the drain mast bolts, and related investigative actions and repair if necessary. We are proposing this AD to detect and correct cracking in the fuselage skin and internal support structure, which could result in uncontrolled decompression of the airplane.

We propose to supersede an existing airworthiness directive (AD) that applies to all The Boeing Company Model 737-100, -200, -200C, -300, -400, and -500 series airplanes. The existing AD currently requires repetitive inspections to detect cracking of the lower corners of the door frame and cross beam of the forward cargo door, and corrective actions if necessary. The existing AD also requires eventual modification of the outboard radius of the lower corners of the door frame and reinforcement of the cross beam of the forward cargo door, which would constitute terminating action for the existing repetitive inspections. Since we issued that AD, we have received additional reports of fatigue cracking in the radius of the lower frames and in the lower number 5 cross beam of the forward cargo door. This proposed AD would revise the compliance times for the preventive modification; add certain inspections for cracks in the number 5 cross beam of the forward cargo door; and add inspections of the number 4 cross beam if cracks are found in the number 5 cross beam, and corrective actions if necessary. For certain airplanes, this proposed AD would also add a one-time inspection for airplanes previously modified or repaired, and a one-time inspection of the reinforcement angle for excessive shimming or fastener pull-up, and corrective actions if necessary. We are proposing this AD to prevent fatigue cracking of the lower corners of the door frame and number 5 cross beam of the forward cargo door, which could result in rapid depressurization of the airplane.

The FAA is issuing this notice to advise the public of the third meeting of RTCA Special Committee 227, Standards of Navigation Performance, (Joint with EUROCAE WG-85).