Boeing Commercial Airplanes

Position: The Boeing Company would like for the FAA to extend the comment period of the referenced NPRM AD for the Model 717-200 from June 25, 2012 for up to 90 additional days (September 25, 2012). This additional time is based on the need to assess the possible impact of the Boeing Alert Service Bulletin (ASB) 717-53A0034, dated October 5, 2011 in the light of recent additional reports of 717 overwing frame cracks and to inform the 717 operators of this condition. Reason for Proposed Request: It has been reported to Boeing on Saturday 31-March 2012, and posted to the FAA as COSP 2012-0155 per the FAA-Boeing COS Agreement, that a 717 airplane was inspected per Alert Service Bulletin (ASB) 717-53A0034 and a Condition No. 3-crack was found on RH frame P/N 9923405-504 at Sta Y=674. Location of crack is at upper radius of frame tab measuring approximately 0.38 inch in length. In addition, it was reported that an ASB Condition 2-crack was found during the same inspection at the corresponding LH frame at Sta Y= 674. This 717-200 fuselage line number had accumulated 22,083 flight hours and 11,991 cycles at the time of inspection. As currently approved, ASB 717-53A0034, in paragraph E. Compliance, states that all airplanes have a compliance time (whichever occurs later) “before the accumulation of 20,000 total flight cycles or within 8275 flight cycles after the original issue date on this service bulletin.” With this recent information, Boeing is seeking additional time to conduct a review, assessment, and the possible impact to the approved ASB based on this new 717 report with this airplane having accumulated flight cycles lower than the first 717 report or on the MD-80 fleet that was used to establish the initial inspection threshold and repetitive inspections for the 717 ASB. In addition, Boeing would need to also inform the FAA and the 717 operators of any changes to be made to the currently approved ASB.