Delta Air Lines

June 2, 2010 U.S. Department of Transportation Docket Operations, M-30, West Building Ground Floor, Room W12-140 1200 New Jersey Avenue SE Washington, DC 20590 Fax: (202) 493-2251 Subject: Docket No. FAA-2010-0430; Directorate Identifier 2010-NM-098-AD: Inspection of Inboard and Outboard Aft Attach Lugs of the Left and Right Elevator Control Tab Mechanism – Immediate Adopted Rule Reference: (A) Immediate Adopted Rule AD 2010-09-05 : Docket No. FAA-2010-0430; Directorate Identifier 2010-NM-098-AD SUMMARY: Reference (A) Immediate Adopted Rule for B737 Next Gen aircraft required inspections of the inboard and outboard aft attach lugs of the left and right elevator control tab mechanism and corrective actions if necessary. DELTA’S COMMENTS The Reference (A) rule affects two Delta B737-700 aircraft which have had the initial inspections accomplished with no discrepancies found. These findings have been reported to Boeing as required by the AD. Delta Air Lines has no objections to this rule. Delta Air Lines does have concerns with the requirements of the terminating action given in Paragraph (r) of the final rule. Paragraph (r) specifies that the repetitive inspections of the elevator tab control mechanism are terminated by the installation of a new, Boeing built mechanism. Service Bulletin 737-27A1297 which is the service documentation mandated by AD 2010-09-05 does not specify a requirement that the replacement mechanism be new in order to terminate the repetitive inspections given in the SB. The SB specifies only that the replacement mechanism be Boeing built in order to terminate the repetitive inspections. The requirement that the Boeing built mechanism be new in order to terminate the repetitive inspections is one that has been added by the FAA. While Note 1 of Paragraph (r) provides instructions to determine whether the mechanism is Boeing built, the AD does not define any method or process to determine if the replacement mechanism is new or not new. The AD therefore is ambiguous in this regard. As the requirement that a replacement mechanism be new in order to terminate the inspection was added by the FAA, the FAA should bear responsibility for defining the method to satisfy this requirement and its inclusion in the AD. Delta Air Lines requests that the FAA provide clarity on this requirement. Delta Air Lines feels that the intent is to install a “new or serviceable unit built by Boeing.” Delta air Lines does not feel that the intent is to install only a new unit to terminate the repetitive inspections of the AD. Delta Air Lines also requests that if the FAA is to add requirements beyond those given in the service documentation (i.e. OEM service bulletin) specified by the AD note, that the FAA define procedures or methods that operators can use to determine if the requirements added by the FAA have been satisfied. In the case of AD 2010-09-05, if the intent is truly install only a “new” unit, Paragraph (r) Note 1 should define methods or procedures to establish whether a replacement mechanism is new or not new. If you have any further questions or require additional information, please contact Dave Fritsch - Sr. Principal Engineer, Department 578, at (404) 714-1466 or email at dave.fritsch@delta.com. Thank you, Craig Amadeo General Manager – Engineering Standards & Chief Engineer Dept. 567