AD 2008-02-13

We are adopting a new airworthiness directive (AD) for all Boeing Model 727 airplanes. This AD requires repetitive external high frequency eddy current (HFEC) inspections of the crown skin for cracks at certain stringer attachment holes, and repair if necessary. This AD results from a report of cracks at multiple locations on certain areas of the crown skin. We are issuing this AD to detect and correct fatigue cracks of the crown skin, which could result in rapid decompression of the airplane.

Final rule.

2008-02-13 Boeing: Amendment 39-15343. Docket No. FAA-2007-28884; Directorate Identifier 2007-NM-116-AD. \n\nEffective Date \n\n\t(a) This airworthiness directive (AD) is effective February 28, 2008. \n\nAffected ADs \n\n\t(b) None. \n\nApplicability \n\n\t(c) This AD applies to all Boeing Model 727, 727C, 727-100, 727- 100C, 727-200, and 727-200F series airplanes, certificated in any category. \n\nUnsafe Condition \n\n\t(d) This AD results from a report of cracks at multiple locations on certain areas of the crown skin. We are issuing this AD to detect and correct fatigue cracks of the crown skin, which could result in rapid decompression of the airplane. \n\nCompliance \n\n\t(e) You are responsible for having the actions required by this AD performed within the compliance times specified, unless the actions have already been done. \n\nRepetitive Inspections and Repair \n\n\t(f) Before the accumulation of 66,000 total flight cycles, or within 3,500 flight cycles after the effective date of this AD, whichever occurs later, do an external high frequency eddy current inspection of the crown skin for cracks at stringer attachment holes between stringer 11 left and stringer 11 right and from body station (BS) 259.5 to BS 1183. Repair any crack found before further flight. Do the actions in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 727-53A0224, dated April 10, 2003, except as provided by paragraph (g) of this AD. Repeat the inspection at intervals not to exceed 3,500 flight cycles. \n\n\t(g) Although Boeing Alert Service Bulletin 727-53A0224, dated April 10, 2003, specifies to submit certain information to the manufacturer, this AD does not include that requirement. \n\nAlternative Methods of Compliance (AMOCs) \n\n\t(h)(1) The Manager, Seattle Aircraft Certification Office (ACO), FAA, has the authority to approve AMOCs for this AD, if requested in accordance with the procedures found in 14 CFR 39.19. \n\n\t(2) To request a different method of compliance or a different compliance time for this AD, follow the procedures in 14 CFR 39.19. Before using any approved AMOC on any airplane to which the AMOC applies, notify your appropriate principal inspector (PI) in the FAA Flight Standards District Office (FSDO), or lacking a PI, your local FSDO. \n\n\t(3) An AMOC that provides an acceptable level of safety may be used for any repair required by this AD, if it is approved by an Authorized Representative for the Boeing Commercial Airplanes Delegation Option Authorization Organization who has been authorized by the Manager, Seattle ACO, to make those findings. For a repair method to be approved, the repair must meet the certification basis of the airplane, and the approval must specifically refer to this AD. \n\nMaterial Incorporated by Reference \n\n\t(i) You must use Boeing Alert Service Bulletin 727-53A0224, dated April 10, 2003, unless the AD specifies otherwise. \n\n\t(1) The Director of the Federal Register approved the incorporation by reference of this service information under 5 U.S.C. 552(a) and 1 CFR part 51. \n\n\t(2) For service information identified in this AD, contact Boeing Commercial Airplanes, P.O. Box 3707, Seattle, Washington 98124-2207. \n\n\t(3) You may review copies of the service information incorporated by reference at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, call 202-741-6030, or go to: http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html .

Discussion \n\n\tWe issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 to include an airworthiness directive (AD) that would apply to all Boeing Model 727 airplanes. That NPRM was published in the Federal Register on August 8, 2007 (72 FR 44433). That NPRM proposed to require repetitive external high frequency eddy current (HFEC) inspections of the crown skin for cracks at certain stringer attachment holes, and repair if necessary. \n\nComments \n\n\tWe gave the public the opportunity to participate in developing this AD. We considered the comment received from the commenter. \n\nRequest to Delegate Approval of Alternative Methods of Compliance (AMOC) for Repairs \n\n\tBoeing requests that paragraph (h) of the NPRM be revised to allow AMOCs for any required repair to be approved by an Authorized Representative for the Boeing Commercial Airplanes Delegation Option Authorization Organization who has been authorized by the Manager, Seattle Aircraft Certification Office. \n\tWe agree with Boeing's request and have revised paragraph (h) of the AD accordingly. \n\nConclusion \n\n\tWe reviewed the relevant data, considered the comment received, and determined that air safety and the public interest require adopting the AD with the change described previously. We also determined that this change will not increase the economic burden on any operator or increase the scope of the AD. \n\nCosts of Compliance \n\n\tThere are about 842 airplanes of the affected design in the worldwide fleet. This AD affects about 459 airplanes of U.S. registry. The inspection takes about 110 work hours per airplane, at an average labor rate of $80 per work hour. Based on these figures, the estimated cost of the AD for U.S. operators is $4,039,200, or $8,800 per airplane, per inspection cycle. \n\nAuthority for This Rulemaking \n\n\tTitle 49 of the United States Code specifies the FAA's authority to issue rules on aviation safety. Subtitle I, section 106,describes the authority of the FAA Administrator. "Subtitle VII: Aviation Programs,'' describes in more detail the scope of the Agency's authority. \n\n\tWe are issuing this rulemaking under the authority described in "Subtitle VII, Part A, Subpart III, Section 44701: General requirements.'' Under that section, Congress charges the FAA with promoting safe flight of civil aircraft in air commerce by prescribing regulations for practices, methods, and procedures the Administrator finds necessary for safety in air commerce. This regulation is within the scope of that authority because it addresses an unsafe condition that is likely to exist or develop on products identified in this rulemaking action. \n\nRegulatory Findings \n\n\tThis AD will not have federalism implications under Executive Order 13132. This AD will not have a substantial direct effect on the States, on the relationship between the national government and the States, or on the distribution of power and responsibilities among the various levels of government. \n\n\tFor the reasons discussed above, I certify that this AD: \n\n\t(1) Is not a "significant regulatory action'' under Executive Order 12866, \n\n\t(2) Is not a "significant rule'' under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979), and \n\n\t(3) Will not have a significant economic impact, positive or negative, on a substantial number of small entities under the criteria of the Regulatory Flexibility Act. \n\n\tYou can find our regulatory evaluation and the estimated costs of compliance in the AD Docket. \n\nList of Subjects in 14 CFR Part 39 \n\n\tAir transportation, Aircraft, Aviation safety, Incorporation by reference, Safety. \n\nAdoption of the Amendment \n\nAccordingly, under the authority delegated to me by the Administrator, the FAA amends 14 CFR part 39 as follows: \n\nPART 39--AIRWORTHINESS DIRECTIVES \n\n1. The authority citation for part 39 continues to read as follows: \n\n\tAuthority: 49 U.S.C. 106(g), 40113, 44701. \n\nSec. 39.13 (Amended) \n\n2. The Federal Aviation Administration (FAA) amends Sec. 39.13 by adding the following new airworthiness directive (AD):