AD 2005-19-24

This amendment supersedes an existing airworthiness directive (AD), applicable to all Boeing Model 727 series airplanes, that currently requires repetitive pre-modification inspections to detect cracks in the forward support fitting of the number 1 and number 3 engines; and repair, if necessary. That AD also provides for an optional high frequency eddy current inspection, and, if possible, modification of the fastener holes; and various follow-on actions; which would terminate the repetitive pre-modification inspections. This amendment expands the area to be inspected; requires accomplishment of the previously optional (and subsequently revised) modification, which terminates certain repetitive inspections; and adds repetitive post- modification inspections to detect cracking of the fastener holes, and corrective actions if necessary. The actions specified by this AD are intended to prevent fatigue cracking of the forward support fitting of the number 1 and number 3 engines, which could result in failure of the support fitting and consequent separation of the engine from the airplane. This action is intended to address the identified unsafe condition. \n\nDATES: Effective October 27, 2005. \n\n\tThe incorporation by reference of Boeing Service Bulletin 727- 54A0010, Revision 6, including Appendix A, dated August 23, 2001, as listed in the regulations, is approved by the Director of the Federal Register as of October 27, 2005. \n\n\tThe incorporation by reference of Boeing Service Bulletin 727- 54A0010, Revision 4, dated January 30, 1997, as listed in the regulations, was approved previously by the Director of the Federal Register as of March 18, 1997 (62 FR 9359, March 3, 1997).

Final rule.

2005-19-24 Boeing: Amendment 39-14289. Docket 2002-NM-66-AD. Supersedes AD 97-05-08, Amendment 39-9952. \n\n\tApplicability: All Model 727 series airplanes, certificated in any category. \n\n\tNote 1: This AD applies to each airplane identified in the preceding applicability provision, regardless of whether it has been modified, altered, or repaired in the area subject to the requirements of this AD. For airplanes that have been modified, altered, or repaired so that the performance of the requirements of this AD is affected, the owner/operator must request approval for an alternative method of compliance in accordance with paragraph (t)(1) of this AD. The request should include an assessment of the effect of the modification, alteration, or repair on the unsafe condition addressed by this AD; and, if the unsafe condition has not been eliminated, the request should include specific proposed actions to address it. \n\n\tCompliance: Required as indicated, unless accomplished previously.To prevent fatigue cracking of the forward support fitting of the number 1 and number 3 engines, which could result in failure of the support fitting and consequent separation of the engine from the airplane, accomplish the following: \n\nRestatement of Requirements of AD 97-05-08 \n\nInspections \n\n\t(a) Within 100 days or 600 flight cycles after March 18, 1997 (the effective date of AD 97-05-08, amendment 39-9952), whichever occurs first, accomplish paragraphs (a)(1), (a)(2), and (a)(3) of this AD, in accordance with Boeing Service Bulletin 727-54A0010, Revision 4, dated January 30, 1997. \n\n\t(1) Perform a visual inspection to detect cracks of the upper and lower flanges, and the vertical web of the forward support fitting of the number 1 and number 3 engines, in accordance with Part 1--Pre-Modification Inspections of the Accomplishment Instructions of the service bulletin. \n\n\t(2) Perform a high frequency eddy current (HFEC) inspection to detect cracks of the forward flange ofthe support fitting adjacent to the collars of two fasteners of the number 1 and number 3 engines, in accordance with Part 1--Pre-Modification Inspections of the Accomplishment Instructions of the service bulletin. \n\n\t(3) Perform a detailed inspection to detect cracks of the upper and lower flanges adjacent to six fasteners of the fitting of the number 1 and number 3 engines, in accordance with Part 1--Pre- Modification Inspections of the Accomplishment Instructions of the service bulletin. \n\n\tNote 2: For the purposes of this AD, a detailed inspection is: "An intensive examination of a specific item, installation, or assembly to detect damage, failure, or irregularity. Available lighting is normally supplemented with a direct source of good lighting at an intensity deemed appropriate. Inspection aids such as mirror, magnifying lenses, etc., may be necessary. Surface cleaning and elaborate procedures may be required." \n\n\t(b) If no crack is detected during the inspections requiredby paragraph (a) of this AD, repeat those inspections thereafter at intervals not to exceed 100 days or 600 flight cycles, whichever occurs first, until the initial inspections required by paragraph (d) of this AD have been accomplished. \n\n\t(c) If any crack is detected during any inspection required by paragraph (a) of this AD, prior to further flight, repair the forward support fitting in accordance with a method approved by the Manager, Seattle Aircraft Certification Office (ACO), FAA. \n\nNew Requirements of This AD \n\n\tNote 3: Where there are differences between the service bulletin and this AD, this AD prevails. \n\nInspections: All Airplanes \n\n\t(d) For all airplanes: Within 600 flight cycles or 100 days after the effective date of this AD, whichever occurs first, inspect the forward support fitting of the number 1 and number 3 engines, as specified in paragraphs (d)(1), (d)(2), (d)(3), (d)(4), and (d)(5) of this AD, in accordance with Part I of the Accomplishment Instructions of Boeing Service Bulletin 727-54A0010, Revision 6, dated August 23, 2001. Accomplishment of these initial inspections terminates the inspection requirements of paragraphs (a) and (b) of this AD. \n\n\t(1) Perform a general visual inspection to detect corrosion and cracking of the fittings in areas inboard of the side of the body, in accordance with Figure 1 of the service bulletin. If any corrosion is found, before further flight, remove the corrosion by accomplishing all of the actions in and in accordance with Figure 5 of the service bulletin, and then perform a general visual inspection to detect cracking of the area, in accordance with the service bulletin. \n\n\tNote 4: For the purposes of this AD, a general visual inspection is: "A visual examination of an interior or exterior area, installation, or assembly to detect obvious damage, failure, or irregularity. This level of inspection is made from within touching distance unless otherwise specified. A mirror may be necessary toensure visual access to all surfaces in the inspection area. This level of inspection is made under normally available lighting conditions such as daylight, hangar lighting, flashlight, or droplight and may require removal or opening of access panels or doors. Stands, ladders, or platforms may be required to gain proximity to the area being checked." \n\n\t(2) Perform an HFEC inspection to detect cracking of the upper and lower horizontal flanges and post tangs of the fittings from inside the airplane, in accordance with Figure 1 of the service bulletin. \n\n\t(3) Perform a general visual inspection to detect cracking and corrosion of the fittings in areas outboard of the side of the body, in accordance with Figure 1 of the service bulletin. If any corrosion is found, before further flight, remove the corrosion by accomplishing all of the actions in and in accordance with Figure 5 of the service bulletin, and perform a general visual inspection to detect cracking of the area, in accordance with the service bulletin. \n\n\t(4) Perform a detailed inspection to detect cracking and corrosion of the web in areas outboard of the side of the body, in accordance with Figure 1 of the service bulletin. If any corrosion is found, before further flight, remove the corrosion in accordance with Figure 5 of the service bulletin, and perform thickness measurements and detailed and HFEC inspections of the vertical web inboard and outboard of the side of the body to detect corrosion and cracking, in accordance with Figure 2 of the service bulletin. If the web thickness is less than 0.130 inch, do paragraph (i) of this AD. \n\n\t(5) Perform detailed and HFEC inspections to detect cracking of the upper and lower horizontal flanges at the side of the body, in accordance with Figure 1 of the service bulletin. \n\nAdditional Inspections: Group 2 Airplanes \n\n\t(e) For Group 2 airplanes, as identified in Boeing Service Bulletin 727-54A0010, Revision 6, dated August 23, 2001: Within 600 flightcycles or 100 days after the effective date of this AD, whichever occurs first, inspect the forward support fitting of the number 1 and number 3 engines at the firewall to detect cracking, as specified in paragraphs (e)(1), (e)(2), (e)(3), and (e)(4) of this AD, in accordance with Part I of the Accomplishment Instructions of the service bulletin. \n\n\t(1) Perform a detailed inspection to detect cracking of the aft side of the upper horizontal flange, in accordance with Figure 1 of the service bulletin. \n\n\t(2) Perform a low frequency eddy current (LFEC) or an open hole HFEC inspection to detect cracking of the aft side of the upper horizontal flange, in accordance with Figure 1 of the service bulletin. \n\n\t(3) Perform a detailed inspection to detect cracking of the aft side of the lower horizontal flange, in accordance with Figure 1 of the service bulletin. \n\n\t(4) Perform an HFEC inspection to detect cracking of the aft side of the lower horizontal flange, in accordance with Figure1 of the service bulletin. \n\nNo Cracking Found: Follow-on Inspections, All Airplanes \n\n\t(f) For all airplanes: If no cracking is found during any inspection required by paragraph (d) of this AD, repeat the applicable inspections within the applicable intervals specified in paragraph 1.E., Table 1, of Boeing Service Bulletin 727-54A0010, Revision 6, dated August 23, 2001, until the modification required by paragraph (j) of this AD has been done. \n\nNo Cracking Found: Additional Follow-on Inspections, Group 2 Airplanes \n\n\t(g) For Group 2 airplanes only: If no cracking is found during the inspections required by paragraph (e) of this AD, repeat the inspections on the upper and lower outboard flange at the firewall within the applicable intervals specified in paragraph 1.E., Table 1, of Boeing Service Bulletin 727-54A0010, Revision 6, dated August 23, 2001. \n\n\t(1) Repeat the inspections of the upper outboard flange at the firewall until the modification required by paragraph (j)of this AD has been done. \n\n\t(2) Repeat the inspections of the lower outboard flange at the firewall indefinitely. There is no terminating action for the inspections of this area. \n\n\tNote 5: Boeing Service Bulletin 727-54A0010, Revision 6, dated August 23, 2001, does not provide instructions for modifying the fastener holes of the lower outboard flange at the firewall. \n\nCracking Found: Any Airplane \n\n\t(h) For any airplane: If any crack is found during any inspection required by paragraph (d), (e), (f), or (g) of this AD, before further flight, do the actions specified in either paragraph (h)(1) or (h)(2) of this AD. \n\n\t(1) Replace or repair the fitting in accordance with a method approved by the Manager, Seattle ACO; or according to data meeting the certification basis of the airplane approved by an Authorized Representative for the Boeing Delegation Option Authorization (DOA) 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; or \n\n\t(2) Do the modification specified in paragraph (j) of this AD. \n\nWeb Thickness Less Than 0.130 Inch: Any Airplane \n\n\t(i) For any airplane: If the web thickness measured during accomplishment of paragraph (d)(4) of this AD is less than 0.130 inch, before further flight, replace or repair the fitting in accordance with a method approved by the Manager, Seattle ACO; or according to data meeting the certification basis of the airplane approved by an Authorized Representative for the Boeing DOA 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\nModification \n\n\t(j) Except as required by paragraphs (h), (i), and (q) of this AD: Within 3,000 flight cycles or 24 months after the effective date of this AD, whichever occurs first, modify the fastener holes, in accordance with Part II of the Accomplishment Instructions of Boeing Service Bulletin 727-54A0010, Revision 6, dated August 23, 2001. Accomplishment of the modification terminates the repetitive inspections required by paragraphs (f) and (g)(1) of this AD. \n\nModification in Accordance With Prior Service Bulletin Revision \n\n\t(k) For airplanes modified before the effective date of this AD in accordance with Boeing Service Bulletin 727-54A0010, Revision 4, dated January 30, 1997: Paragraph (j) of this AD requires accomplishment of additional procedures in accordance with Revision 6 of the service bulletin. To the extent that certain modification procedures were performed in accordance with Revision 4, those actions do not need to be repeated when performing the modification required in paragraph (j) of this AD.\n \n\t(l) A modification done before the effective date of this ADin accordance with Boeing Alert Service Bulletin 727-54A0010, Revision 5, dated February 15, 2001, is acceptable for compliance with the requirements of paragraph (j) of this AD. \n\nPost-Modification Inspections \n\n\t(m) Inspect as specified in paragraphs (m)(1), (m)(2), and (n) of this AD, as applicable, to detect cracking and corrosion, in accordance with Part III of the Accomplishment Instructions of Boeing Service Bulletin 727-54A0010, Revision 6, dated August 23, 2001. Inspections done before the effective date of this AD in accordance with Part III of Boeing Alert Service Bulletin 727- 54A0010, Revision 5, dated February 15, 2001, are acceptable for compliance with the corresponding inspection requirements of this paragraph. \n\n\t(1) For all airplanes: Do an open hole HFEC inspection of the fastener holes in the forward support fitting of the number 1 and number 3 engines, at the locations shown in Figure 4 of the service bulletin. \n\n\t(2) For Group 2 airplanes: Do an open holeHFEC inspection of the fastener holes in the forward support fitting of the number 1 and number 3 engines, at the locations shown in Figure 4 of the service bulletin. \n\n\t(n) Perform the inspections specified in paragraph (m) of this AD at the later of the times specified in paragraphs (n)(1) and (n)(2) of this AD. \n\n\t(1) Within 3,000 flight cycles or 24 months, whichever occurs first, after accomplishment of the modification required by paragraph (j) of this AD. \n\n\t(2) Within 600 flight cycles or 100 days, whichever occurs first, after the effective date of this AD. \n\nFollow-On/Corrective Actions \n\n\t(o) If no cracking is found during any inspection required by paragraph (m) of this AD: Repeat the inspections specified in paragraph (m) of this AD thereafter within the applicable intervals specified in paragraph 1.E., Table 1, of Boeing Service Bulletin 727-54A0010, Revision 6, dated August 23, 2001. Accomplishment of the modification specified in paragraph (j) of this AD doesnot terminate the requirement to repetitively perform the post- modification inspections specified in Part III of the service bulletin. \n\n\t(p) If any cracking is detected during any inspection required by paragraph (m) of this AD: Before further flight, repair in accordance with Boeing Service Bulletin 727-54A0010, Revision 6, dated August 23, 2001; except as required by paragraph (q) of this AD. \n\nException to Corrective Actions \n\n\t(q) Where Boeing Service Bulletin 727-54A0010, Revision 6, dated August 23, 2001, specifies to contact Boeing for appropriate action: Before further flight, replace or repair the fitting in accordance with a method approved by the Manager, Seattle ACO; or according to data meeting the certification basis of the airplane approved by an Authorized Representative for the Boeing DOA 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 ofthe airplane, and the approval must specifically refer to this AD. \n\nReporting Not Required \n\n\t(r) Boeing Service Bulletin 727-54A0010, Revision 6, dated August 23, 2001, recommends that operators report inspection results to the manufacturer; however, this AD does not contain this requirement. \n\nParts Installation \n\n\t(s) As of the effective date of this AD, no person may install a forward support fitting on any airplane, unless it has been inspected and modified, as applicable, in accordance with the requirements of this AD. \n\nAlternative Methods of Compliance \n\n\t(t)(1) The Manager, Seattle 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) AMOCs previously approved according to AD 97-05-08 are acceptable for compliance with the corresponding requirements of this AD. \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 DOA 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\n\tNote 6: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Seattle ACO. \n\nSpecial Flight Permits \n\n\t(u) Special flight permits may be issued according to sections 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 21.197 and 21.199) to operate the airplane to a location where the requirements of this AD can be accomplished. \n\nIncorporation by Reference \n\n\t(v) Unless otherwise specified in this AD, the actions must be done in accordance with Boeing Service Bulletin 727-54A0010, Revision 4, dated January 30, 1997; and Boeing Service Bulletin 727- 54A0010, Revision 6, including Appendix A, dated August 23, 2001; as applicable. \n\n\t(1) The incorporation by reference of Boeing Service Bulletin 727-54A0010, Revision 6, including Appendix A, dated August 23, 2001, is approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. \n\n\t(2) The incorporation by reference of Boeing Service Bulletin 727-54A0010, Revision 4, dated January 30, 1997, was approved previously by the Director of the Federal Register as of March 18, 1997 (62 FR 9359, March 3, 1997). \n\n\t(3) Copies may be obtained from Boeing Commercial Airplanes, P.O. Box 3707, Seattle, Washington 98124-2207. Copies may be inspected 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 the NARA, call (202) 741-6030, or go to http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html . \n\nEffective Date(w) This amendment becomes effective on October 27, 2005.

A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) by superseding AD 97-05-08, amendment 39-9952 (62 FR 9359, March 3, 1997), which is applicable to all Boeing Model 727 series airplanes, was published in the Federal Register on May 1, 2003 (68 FR 23231). The action proposed to continue to require repetitive pre-modification inspections to detect cracks in the forward support fitting of the number 1 and number 3 engines, and repair if necessary. The action also proposed to expand the area to be inspected; require accomplishment of the previously optional (and subsequently revised) modification, which would terminate certain repetitive inspections; and add repetitive post-modification inspections to detect cracking of the fastener holes, and corrective actions if necessary. \n\nComments \n\n\tInterested persons have been afforded an opportunity to participate in the making of this amendment. Due consideration has been given to thecomments received. \n\nRequests To Revise the Applicability \n\n\tOne commenter requests that the applicability of the proposed AD be revised to apply only to Boeing Model 727 airplanes equipped with fittings having part number (P/N) 65-18722-xx. The commenter states that its Model 727-100 fleet does not include any airplanes equipped with fittings having that P/N. Because it changed the affected fittings during a re-engine modification in accordance with Supplemental Type Certificate (STC) SA8472SW, it was granted an alternate method of compliance (AMOC) for AD 97-05-08. The commenter asserts that revising the proposed applicability will prevent operators that do not have the affected fittings installed from having to request an AMOC for the requirements of the proposed AD. \n\n\tAnother commenter requests that a statement be added to the proposed AD to exempt airplanes modified in accordance with STC SA4363NM. The commenter asserts that inclusion of this statement will make it perfectly clear to operators whether or not they are in compliance with the AD. \n\n\tWe acknowledge the commenters' concern and, as we state in paragraph (t)(2) of this AD, AMOCs previously approved according to AD 97-05-08 are acceptable for compliance with the corresponding requirements of this AD. These AMOCs address the commenter's concern. We find that no further clarifications are necessary and have made no change to the final rule in this regard. \n\nRequest To Add Language Specific to Airplanes With "Hush Kit" STCs Installed \n\n\tA third commenter requests that specific language be included in the final rule stating that airplanes modified in accordance with STCs SA3993NM, SA4833NM, SA5839NM, and ST00350AT may be inspected and modified in accordance with Boeing Service Bulletin 727-54A0010, Revision 6, without change. (Boeing Service Bulletin 727-54A0010, Revision 6, dated August 23, 2001, was referenced in the proposed AD as the appropriate source of service information for accomplishing the new actions). These STCs install noise suppression modification equipment (hush kits) on Model 727 airplanes. The commenter states that including this information in the AD, in lieu of making operators request AMOCs, will avoid confusion among operators with airplanes equipped with these STCs. The commenter submitted substantiating data to support its request. \n\n\tWe do not agree. The static strength data analysis of the affected structure submitted was not sufficient to show that the commenter's request would result in an acceptable level of safety. Damage tolerance assessment is needed to determine if the inspections and modifications described in Boeing Service Bulletin 727-54A0010, Revision 6, are appropriate for airplanes modified in accordance with these STCs. In this case, the ability to inspect the affected area and changes in fatigue stress levels need to be addressed. Additionally, the inspections and modifications specified in the service bulletin specifically address only affected original equipment manufacturer configurations. However, as we explained previously, we will consider requests for AMOCs submitted with sufficient technical justification to support the request. We have made no change to the final rule regarding this issue. \n\nRequest To Change the Method of Inspection \n\n\tAnother commenter, the manufacturer, requests that we revise paragraphs (d)(1) and (d)(3) of the proposed AD to revise the method of inspection. Specifically, the commenter recommends revising "* * * If any corrosion is found, before further flight, remove the corrosion in accordance with Figure 5 of the service bulletin, and perform a general visual inspection to detect cracking * * *" to read "* * * If any corrosion is found, before further flight, remove the corrosion in accordance with Figure 5 of the service bulletin, and perform a HFEC inspection to detect cracking * * *." The commenter asserts that the high frequency eddy current (HFEC) inspection is a better method than a surveillance inspection and will provide an adequate level of safety by enabling operators to find small cracks. \n\n\tWe partially agree with the commenter. We find that an HFEC inspection should be accomplished after removal of corrosion. However, we do not agree that it is necessary to revise paragraphs (d)(1) and (d)(3) of this final rule as requested. Paragraphs (d)(1) and (d)(3) require any corrosion found to be removed in accordance with Figure 5 of Boeing Service Bulletin 727-54A0010, Revision 6, dated August 23, 2001. Step 5 of Figure 5 of the service bulletin includes procedures for doing an HFEC inspection for cracks and repairing any cracks found once the corrosion has been identified and removed from the affected area. The general visual inspection required by paragraphs (d)(1) and (d)(3) follows the instructions given in Figure 1, Step 2, of the service bulletin. We find that no change to the final rule is necessary regarding this issue. \n\nRequest To Refer Specifically to Post-Modification Inspections \n\n\tThe same commenter also requests that paragraph (m) of the proposed AD be revised to refer to the post-modification inspections in Revision 5 of Boeing Alert Service Bulletin 727-54A0010, dated February 15, 2001. Specifically, the commenter recommends revising "* * * Inspections done before the effective date of this AD in accordance with Boeing Alert Service Bulletin 727-54A0010, Revision 5, dated February 15, 2001, are acceptable for compliance with the corresponding inspection requirements of this paragraph * * *." to "* * * Inspections done before the effective date of this AD in accordance with Part III of the Accomplishment Instructions of Boeing Alert Service Bulletin 727-54A0010, Revision 5, dated February 15, 2001, are acceptable for compliance with the corresponding inspection requirements of this paragraph * * *." The commenter believes that, for airplanes that have accomplished the modification, only the repeat post-modification inspection requirements of Revision 5 of the service bulletin provide an equivalent level of safety for the fleet. \n\n\tWe agree with the request for the reason provided by the commenter. It was our intent to refer specifically to Part III of the Accomplishment Instructions of Revision 5 of the service bulletin in paragraph (m). Therefore, we have revised paragraph (m) of this final rule to specifically refer to Part III of the Accomplishment Instructions of Revision 5 of the service bulletin for accomplishment of post-modification inspections done before the effective date of the AD. \n\nExplanation of Additional Changes to the Proposed AD \n\n\tBoeing has received a Delegation Option Authorization (DOA). We have revised this final rule to delegate the authority to approve an alternative method of compliance for any repair required by this AD to the Authorized Representative for the Boeing DOA Organization rather than the Designated Engineering Representative (DER). Accordingly, we have added paragraph (t)(3) to this final rule and revised the wording of paragraphs (h)(1) and (i) of this AD. We have also revised the wording of paragraph (t)(1) of this final rule (specified as paragraph (s)(1) in the proposed AD) for reasons discussed under "Changes to 14 CFR part 39/Effect on the AD." \n\n\tBecause the language in Note 6 of the proposed AD is regulatory in nature, that note has been redesignated as paragraph (r) of this final rule. We have re-identified subsequent notes and paragraphs accordingly. \n\nConclusion \n\n\tAfter careful review of the available data, including the comments noted above, the FAA has determined that air safety and the public interest require the adoption of the rule with the changes previously described. The FAA has determined that these changes will neither increase the economic burden on any operator nor increase the scope of the AD. \n\nChanges to 14 CFR Part 39/Effect on the AD \n\n\tOn July 10, 2002, the FAA issued a new version of14 CFR part 39 (67 FR 47997, July 22, 2002), which governs the FAA's airworthiness directives system. The regulation now includes material that relates to altered products, special flight permits, and AMOCs. Because we have now included this material in part 39, only the office authorized to approve AMOCs is identified in each individual AD. However, for clarity and consistency in this final rule, we have retained the language of the NPRM regarding that material, except for the revisions to certain language discussed previously. \n\nChange to Labor Rate Estimate and Airplane Fleet Data \n\n\tWe have reviewed the figures we have used over the past several years to calculate AD costs to operators. To account for various inflationary costs in the airline industry, we find it necessary to increase the labor rate used in these calculations from $60 per work hour to $65 per work hour. The cost impact information, below, reflects this increase in the specified hourly labor rate. \n\n\tWe havealso revised the cost impact information to more accurately describe the number of airplanes of the affected design in the current worldwide and U.S. fleets. \n\nCost Impact \n\n\tThere are approximately 1,009 airplanes of the affected design in the worldwide fleet. The FAA estimates that 587 airplanes of U.S. registry will be affected by this AD. \n\n\tWe provide the following cost estimates for this AD: \n\n\nAction \nWork hours \nAverage labor rate per hour \nCost of parts \nCost per airplane \nCost for the U.S. fleet \n\n\n\n\n\n\nAD 97-05-08 inspections, per inspection cycle. \n2 \n$65 \n$0 \n$130 \n$76,310, per inspection cycle. \n\n\n\n\n\n\nInspections before structural rework, per inspection cycle. \n14 \n65 \n0 \n910 \n534,170, per inspection cycle. \nStructural rework \n7 \n65 \n7,875 \n8,330 \n4,889,710. \n\n\n\n\n\n\nInspections after structural rework, per inspection cycle. \n12 \n65 \n0 \n780 \n457,860, per inspection cycle. \n\n\n\tThe cost impact figures discussed above are based on assumptions that no operator has yet accomplished any of the requirements of this AD action, and that no operator would accomplish those actions in the future if this AD were not adopted. The cost impact figures discussed in AD rulemaking actions represent only the time necessary to perform the specific actions actually required by the AD. These figures typically do not include incidental costs, such as the time required to gain access and close up, planning time, or time necessitated by other administrative actions. \n\nRegulatory Impact \n\n\tThe regulations adopted herein 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. Therefore, it is determined that this final rule does not have federalism implications under Executive Order 13132. \n\n\tFor the reasons discussed above, I certify that this action (1) is not a "significant regulatory action" under Executive Order 12866; (2) is not a "significant rule" under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and (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. A final evaluation has been prepared for this action and it is contained in the Rules Docket. A copy of it may be obtained from the Rules Docket at the location provided under the caption ADDRESSES. \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, pursuant to the authority delegated to me by the Administrator, the Federal Aviation Administration amends part 39 of the Federal Aviation Regulations (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. Section 39.13 is amended by removing amendment 39-9952 (62 FR 9359, March 3, 1997), and by adding a new airworthiness directive (AD), amendment 39-14289, to read as follows: