AD 2007-21-18

The FAA is adopting a new airworthiness directive (AD) for certain McDonnell Douglas airplanes, identified above. This AD requires a one-time inspection to determine the configuration of the airplane. This AD also requires repetitive inspections for cracking of the tee or angle doubler, and corrective actions if necessary. This AD results from a report indicating that numerous operators have found cracks on the tee. We are issuing this AD to detect and correct stress corrosion cracking of the tee or angle doubler installed on the flat aft pressure bulkhead. Cracking in this area could continue to progress and damage the adjacent structure, which could result in loss of structural integrity of the airplane.

Final rule.

2007-21-18 McDonnell Douglas: Amendment 39-15236. Docket No. FAA- 2007-27777; Directorate Identifier 2006-NM-265-AD. \n\nEffective Date \n\n\t(a) This AD becomes effective November 28, 2007. \n\nAffected ADs \n\n\t(b) None. \n\nApplicability \n\n\t(c) This AD applies to McDonnell Douglas Model DC-8-53, DC-8-55, DC-8-61, DC-8-61F, DC-8-62, DC-8-62F, DC-8-63, DC-8-63F, DC-8-71, DC-8-71F, DC-8-72, DC-8-72F, DC-8-73, DC-8-73F, DC-8F-54, and DC-8F- 55 airplanes, certificated in any category; as identified in Boeing Alert Service Bulletin DC8-53A081, dated November 14, 2006. \n\nUnsafe Condition \n\n\t(d) This AD results from a report indicating that numerous operators have found cracks on the tee installed on the left and right side of the flat aft pressure bulkhead from Longeron 9 to Longeron 13. We are issuing this AD to detect and correct stress corrosion cracking of the tee or angle doubler installed on the flat aft pressure bulkhead. Cracking in this area could continue to progress and damage the adjacent structure, which could result in loss of structural integrity 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\nInspections and Related Investigative/Corrective Actions \n\n\t(f) For all airplanes: Within 24 months after the effective date of this AD, inspect the left and right sides of the flat aft pressure bulkhead to determine if a repair has been installed. As noted in Boeing Alert Service Bulletin DC8-53A081, dated November 14, 2006, Configuration 1 applies to airplanes with no repairs installed; Configuration 2 applies to airplanes with repairs installed in accordance with DC-8 Structural Repair Manual (SRM) 53- 2-5, Figure 9; and Configuration 3 applies to airplanes with repairs that are not installed in accordance with DC-8 SRM 53-2-5, Figure 9. A review of airplane maintenance records is acceptable in lieu of this inspection if the applicable installation can be conclusively determined from that review. \n\n\t(1) For airplanes determined to be either Configuration 1 or Configuration 2: Within 24 months after the effective date of this AD, do the applicable inspection for cracking of the tee or angle doubler, and do all applicable corrective actions before further flight, by accomplishing all the actions specified in the Accomplishment Instructions of Boeing Alert Service Bulletin DC8- 53A081, dated November 14, 2006. Repeat the applicable inspection thereafter at the applicable interval specified in Paragraph 1.E, "Compliance,'' of Boeing Alert Service Bulletin DC8-53A081, dated November 14, 2006. Where the service bulletin specifies to do the pressure test, that action is not required by this AD. \n\n\t(2) For airplanes determined to be Configuration 1 airplanes: A review of the airplane maintenance records to determine if the tee was previously inspected using one of the three inspection methods specified in the DC-8 Supplemental Inspection Document (SID) L26- 011, Volume II, 53-10-18, and to determine that no crack was found, is acceptable to determine the type of inspection and corresponding repetitive interval if the inspection type and crack finding can be conclusively determined from that review. \n\n\t(3) For airplanes determined to be Configuration 3 airplanes: Within 24 months after the effective date of this AD, repair the previous installation. Where Boeing Alert Service Bulletin DC8- 53A081, dated November 14, 2006, specifies to contact Boeing for instructions, repair using a method approved in accordance with the procedures specified in paragraph (g) of this AD. \n\nAlternative Methods of Compliance (AMOCs) \n\n\t(g)(1) The Manager, Los Angeles 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, Los Angeles ACO, to make those findings. For a repair method to be approved, the repair must meet the certification basis of the airplane and 14 CFR 25.571, Amendment 45, and the approval must specifically refer to this AD. \n\n\t(4) Inspections and repairs required by this AD of specified areas of Principal Structural Elements (PSEs) 53.08.009 and 53.08.010 are acceptable for compliance with the applicable requirements of paragraphs(a) and (b) of AD 93-01-15, amendment 39-8469, including the reporting requirements for those specified areas. The remaining areas of the affected PSEs must continue to be inspected and repaired, as applicable, in accordance with AD 93-01-15. \n\t(5) AMOCs for repairs granted previously in accordance with AD 93- 01-15 are acceptable for compliance with the corresponding actions required by this AD. \n\nMaterial Incorporated by Reference \n\n\t(h) You must use Boeing Alert Service Bulletin DC8-53A081, dated November 14, 2006, to perform the actions that are required by this AD, unless the AD specifies otherwise. The Director of the Federal Register approved the incorporation by reference of this document in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Contact Boeing Commercial Airplanes, Long Beach Division, 3855 Lakewood Boulevard, Long Beach, California 90846, Attention: Data and Service Management, Dept. C1-L5A (D800-0024), for a copy of this service information. You may review copies 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/cfr/ibr-locations.html .

Discussion \n\n\tThe FAA issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 to include an AD that would apply to certain McDonnell Douglas Model DC-8-53, DC-8-55, DC-8F-54, and DC-8F-55 airplanes; and Model DC-8-60, DC-8-60F, DC-8-70, and DC-8-70F series airplanes. That NPRM was published in the Federal Register on April 5, 2007 (72 FR 16744). That NPRM proposed to require a one-time inspection to determine the configuration of the airplane. That NPRM also proposed to require repetitive inspections for cracking of the tee or angle doubler, and corrective actions if necessary. \n\nComments \n\n\tWe provided the public the opportunity to participate in the development of this AD. We have considered the comments received. \n\nRequest To Clarify Paragraph (f) of the NPRM \n\n\tAir Transport Association (ATA), on behalf of its member UPS, requests that we reword the first section of paragraph (f) of the NPRM for clarity. The commenters state that paragraph (f) of the NPRM mandates an inspection to determine if a tee or angle is installed. The commenters point out that all airplanes have a tee installed, as this is the baseline configuration, and that the angle is a repair on top of the tee. UPS suggests that we revise the paragraph to state instead, " * * * inspect the left and right side of the flat aft pressure bulkheadto determine if a repair has been installed. As noted in Boeing Service Bulletin DC8-53A081, Configuration 1 applies to airplanes with no repairs installed; Configuration 2 applies to airplanes with repairs installed in accordance with DC-8 SRM 53-2-5, Figure 9; and Configuration 3 applies to repairs which are not installed in accordance with DC-8 SRM 53-2-5, Figure 9 * * *'' \n\n\tIn addition, ABX Air, Inc. and UPS request that we fix a typographical error in paragraph (f). The Structural Repair Manual (SRM) reference should be 53-2-5 rather than 52-2-5. \n\n\tWe agree with the ATA and UPS because the suggested wording is more accurate and clear than the wording in the NPRM. We have revised paragraph (f) of this AD accordingly. We have also revised the Summary and Discussion sections of the preamble of this AD to state that the one-time inspection is simply to determine the configuration of the airplane. We have also changed the SRM reference in the AD, as requested. Operators should note that the reference to this SRM should also be 53-2-5 rather than 52-2-5 in Table 3 of Paragraph 1.E., Compliance, of Boeing Alert Service Bulletin DC8-53A081, dated November 14, 2006. \n\nRequest To Clarify Pressure Test Requirement \n\n\tATA, on behalf of its member UPS, notes that paragraph (f)(1) of the NPRM requires accomplishment of all applicable actions specified in the Accomplishment Instructions of Boeing Alert Service Bulletin DC8- 53A081, dated November 14, 2006. UPS states that the applicable actions in paragraph B.4 of those instructions include a pressure test of the fuselage as given in theDC-8 aircraft maintenance manual 21-31-0. The commenters do not believe that the pressure test is necessary to accomplish either the inspections or repairs successfully. They note that Boeing concurs with deleting this requirement, and refer to Boeing Message 1-283162455-4, dated February 12, 2007, as the relevant correspondence between Boeing and UPS. \n\n\tWe agree that the pressure test is not necessary for accomplishing either the inspections or repairs. We have added a sentence to paragraph (f)(1) of this AD to state that where the service bulletin specifies to do the pressure test, that action is not required by this AD. \n\nRequests To Supersede AD 93-01-15 \n\n\tThe same commenters have three requests related to AD 93-01-15, amendment 39-8469 (58 FR 5576, January 22, 1993). The commenters believe that the AD resulting from the NPRM should supersede AD 93-01- 15 for the area of concern, which is Principal Structural Element (PSE) 53.08.009 and PSE 53.08.010. The commenters also believe that the AD resulting from the NPRM should specifically mention that it removes the reporting requirements of AD 93-01-15 for the area of concern. UPS notes that a similar request to remove the reporting requirements was granted as an alternative method of compliance (AMOC) approval for all airplanes affected by AD 2006-03-04, amendment 39-14468 (71 FR 5969, February 6, 2006). UPS also requests that we revise paragraph (g) of the NPRM (the AMOC paragraph) to mention that prior AMOC approvals for AD 93-01-15 for repairs in the area of concern be automatically accepted as AMOCs for this new AD. \n\n\tWe partially agree with the commenters. We agree that inspections and repairs required by this AD of specified areas of PSEs 53.08.009 and 53.08.010 are acceptable for compliance with the applicable requirements of paragraphs (a) and (b) of AD 93-01-15, including the reporting requirements for those specified areas. The remaining areas of the affected PSEs must be inspected and repaired, as applicable, in accordance with AD 93-01-15. We also agree that AMOCs for repairs granted previously in accordance with AD 93-01-15 are acceptable for compliance with the corresponding actions required by this AD. We have added new paragraphs (g)(4) and (g)(5) to this AD to address these requests. \n\n\tWe do not agree that it is necessary to supersede AD 93-01-15. We find that the revisions to this AD are sufficient to address the area of concern noted by the commenters. \n\nConclusion \n\n\tWe have carefully reviewed the available data, including the comments received, and determined that air safety and the public interest require adopting the AD with the changes described previously. We have determined that these changes will neither increase the economic burden on any operator nor increase the scope of the AD. \n\nCosts of Compliance \n\n\tThere are about 321 airplanes of the affected design in the worldwide fleet. This AD affects about 139 airplanes of U.S. registry. The following table provides the estimated costs for U.S. operators to comply with this AD. The average labor rate is $80 per work hour. \n\n\tEstimated Costs\n\n\nAction\nWork hours\nCost per airplane\nFleet cost\nInspection to determine the configuration of the airplane, and to determine previous inspection method\n1\n$80\n$11,120\nConfiguration 1, per inspection cycle\n11\n$880, per inspection cycle\nUp to $122,320, per inspection cycle\nConfiguration 2, per inspection cycle\n5\n$400, per inspection cycle\nUp to $55,600, 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\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\tWe have determined that this 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\t(2) Is not a "significant rule'' under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and \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\tWe prepared a regulatory evaluation of the estimated costs to comply with this AD and placed it in the AD docket. See the ADDRESSES section for a location to examine the regulatory evaluation. \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):