AD 2005-04-14 R1

The FAA is revising an existing airworthiness directive (AD), which applies to certain Boeing Model 757-200, 757-200CB, and 757-200PF series airplanes. That AD currently requires repetitive inspections to detect horizontal or vertical movement of the shims at the joint of the mid-bulkhead and the upper link fittings; repetitive inspections for cracking of the mid-bulkhead; and corrective action if necessary. That AD also provides optional terminating action for the repetitive inspections. This AD continues to require the existing requirements and optional actions and clarifies certain terminating actions. This AD results from comments received in response to an existing AD, requesting clarification. We are issuing this AD to detect and correct migration of shims at the joint of the mid-bulkhead and the upper link fittings and cracking of the mid-bulkhead, which could result in cracking of the strut and consequent loss of the strut and engine. \n\nDATES: Effective March 15, 2005. \n\n\tOn March 15, 2005 (70 FR 9511, February 28, 2005), the Director of the Federal Register approved the incorporation by reference of Boeing Service Bulletin 757-54A0039, Revision 2, dated December 2, 2004; and Boeing Service Bulletin 757-54A0039, Revision 3, dated January 13, 2005. \n\n\tOn April 18, 2003 (68 FR 16200, April 3, 2003), the Director of the Federal Register approved the incorporation by reference of Boeing Alert Service Bulletin 757-54A0039, Revision 1, dated June 20, 2002. \n\n\tWe must receive any comments on this AD by October 11, 2005.

Final rule; request for comments.

2005-04-14 R1 Boeing: Amendment 39-14216. Docket No. FAA-2005-22054; Directorate Identifier 2005-NM-137-AD. \n\nEffective Date \n\n\t(a) The effective date of this AD is March 15, 2005. \n\nAffected ADs \n\n\t(b) This AD revises AD 2005-04-14, amendment 39-13986. \n\nApplicability \n\n\t(c) This AD applies to Boeing Model 757-200, 757-200CB, and 757- 200PF series airplanes; certificated in any category; equipped with Rolls Royce Model RB211 engines; as identified in Boeing Service Bulletin 757-54A0039, Revision 3, dated January 13, 2005. \n\nUnsafe Condition \n\n\t(d) This AD was prompted by reports of cracks in the mid- bulkhead lower vertical flange common to the lower chord and stiffener and reports of cracking at other locations on the mid- bulkhead. We are issuing this AD to detect and correct migration of shims at the joint of the mid-bulkhead and the upper link fittings and cracking on the mid-bulkhead, which could result in cracking of the strut and consequent loss of the strut andengine. \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\nRequirements of 2005-04-14 \n\nInspection for Movement of Shims and Corrective Actions \n\n\t(f) For Groups 1 and 2 airplanes, as identified in Boeing Alert Service Bulletin (ASB) 757-54A0039, Revision 1, dated June 20, 2002; Boeing Service Bulletin (SB) 757-54A0039, Revision 2, dated December 2, 2004; and Boeing SB 757-54A0039, Revision 3, dated January 13, 2005; with the exception of the airplanes specified in paragraph (j) of this AD: Within 90 days after April 18, 2003 (the effective date of AD 2003-07-08, amendment 39-13104), perform a detailed inspection to detect horizontal or vertical movement of the shims at the joint of the mid-bulkhead and the upper link fittings, per Boeing ASB 757- 54A0039, Revision 1, dated June 20, 2002; or Boeing SB 757-54A0039, Revision 2, dated December 2, 2004, or Revision 3, dated January 13, 2005. \n\n\tNote 1: For the purposes of this AD, a detailed inspection is defined as: "An intensive visual examination of a specific structural area, system, installation, or assembly to detect damage, failure, or irregularity. Available lighting is normally supplemented with a direct source of good lighting at intensity deemed appropriate by the inspector. Inspection aids such as mirror, magnifying lenses, etc., may be used. Surface cleaning and elaborate access procedures may be required." \n\n\t(g) If all laminated shims have not moved, or if all laminated shims have moved less than 0.25 inch: Before further flight, perform the actions specified in either paragraph (g)(1) or (g)(2) of this AD, per Boeing ASB 757-54A0039, Revision 1, dated June 20, 2002; or Boeing SB 757-54A0039, Revision 2, dated December 2, 2004, or Revision 3, dated January 13, 2005. \n\n\t(1) Perform the actions specified in paragraph 3.B.6 of the Accomplishment Instructions of the ASB (e.g., measure and record movement of the shim, cut the exposed plies, and seal adjacent surfaces and edges), and repeat the detailed inspections at intervals not to exceed 12,000 flight cycles or 72 months, whichever occurs first. At each inspection interval, the previously recorded measurement must be added to the current measurement so that the cumulative total movement of the shim is recorded. If the cumulative total movement exceeds 0.25 inch but is less than 0.90 inch, before further flight, perform the actions specified in paragraph (h) of this AD. If the cumulative total movement measures 0.90 inch or more: Before further flight, perform the actions specified in paragraph (i) of this AD. Or \n\n\t(2) Perform the actions specified in paragraphs (l) and (m) of this AD. \n\n\t(h) If any laminated shim has moved 0.25 inch or more but less than 0.90 inch: Before further flight, perform the actions specified in paragraph (h)(1) or (h)(2) of this AD, per Boeing ASB 757- 54A0039, Revision 1, dated June 20, 2002; or Boeing SB 757-54A0039, Revision 2, dated December 2, 2004, or Revision 3, dated January 13, 2005. \n\n\t(1) Before further flight, perform the actions specified in paragraph 3.B.6 of the Accomplishment Instructions of the ASB (e.g., measure and record movement of the shim, cut the exposed plies and seal adjacent surfaces and edges), and repeat the detailed inspections at intervals not to exceed 3,000 flight cycles or 18 months, whichever occurs first. At each inspection interval, the previously recorded measurement must be added to the current measurement so that the cumulative total movement of the shim is recorded. If the cumulative total movement measures 0.90 inch or more, before further flight, perform the actions specified in paragraph (i) of this AD. Or, \n\n\t(2) Perform the actions specified in paragraphs (l) and (m) of this AD. \n\n\t(i) If any laminated shim has moved 0.90 inch or more: Before further flight, perform the actions specified in paragraphs (l) and (m) of this AD. \n\nInspection of Lower Mid-Spar Bolts \n\n\t(j) For airplanes on which the actions specified in Boeing ASB 757-54A0039, dated November 2, 2000, have been accomplished prior to April 18, 2003: Within 90 days after April 18, 2003, perform a detailed inspection for cracking around the four bolt heads, nuts, washers, and radius fillers specified in Figure 9 of Boeing ASB 757- 54A0039, Revision 1, dated June 20, 2002; or Boeing SB 757-54A0039, Revision 2, dated December 2, 2004, or Revision 3, dated January 13, 2005. \n\n\t(1) If no cracking is found, repeat the detailed inspection at intervals not to exceed 3,000 flight cycles. \n\n\t(2) If any cracking is found, before further flight, repair per a method approved by the Manager, Seattle Aircraft Certification Office (ACO), FAA; or per data meeting the type certification basis of the airplane approved by a Boeing Company Designated Engineering Representative (DER) who has been authorized by the Manager, SeattleACO, to make such findings; or by an Authorized Representative (AR) 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 approval must specifically reference this AD. \n\nTerminating Action for Certain Requirements of This AD \n\n\t(k) For Groups 1, 2, and 3, as identified in Boeing SB 757- 54A0039, Revision 2, dated December 2, 2004; or Revision 3, dated January 13, 2005: Accomplishment of the actions specified in paragraphs (l) and (m) of this AD constitutes terminating action for the repetitive inspection requirements of paragraphs (g)(1), (h)(1), and (r)(1) of this AD. Accomplishment of paragraphs (l) and (m) of this AD also constitutes terminating action for paragraphs (o), (p), and (q), if accomplished prior to March 15, 2005 (the effective date of AD 2005-04-14). For airplanes specified in paragraph (j) of this AD, accomplishment of paragraph (m) of this AD constitutes terminating action for paragraph (j) of this AD. \n\n\t(l) Replace any laminated shim with a solid shim; replace existing sleevebolts with new, oversized sleevebolts; and perform a general visual and high-frequency eddy current (HFEC) inspection to detect cracking and deformation in the sleevebolt holes and in the fittings, as shown in Part II, Figure 3, of Boeing ASB 757-54A0039, Revision 1, dated June 20, 2002; or Boeing SB 757-54A0039, Revision 2, dated December 2, 2004, or Revision 3, dated January 13, 2005. If any shim cannot be removed, or if any cracking or deformation is found: Before further flight, repair per a method approved by the Manager, Seattle ACO, FAA; or per data meeting the type certification basis of the airplane approved by a Boeing DER who has been authorized by the Manager, Seattle ACO, to make such findings; or by an AR for the Boeing DOA Organization who has been authorized by the Manager, Seattle ACO, to make those findings. For a repair to be approved, the approval must specifically reference this AD. No further action is required by this paragraph. \n\n\t(m) Perform a one-time HFEC inspection for cracking in and around the bolt holes of the left and right side of the mid-bulkhead strut as shown in Part III, Figure 9, of Boeing ASB 757-54A0039, Revision 1, dated June 20, 2002; or Boeing SB 757-54A0039, Revision 2, dated December 2, 2004, or Revision 3, dated January 13, 2005. \n\n\t(1) If no cracking is found during any inspection specified in paragraph (m) of this AD, before further flight, install oversized bolts per Figure 10 of the ASB. No further action is required by this paragraph. \n\n\t(2) If any cracking is found during any inspection specified in paragraph (m) of this AD that is within the limits specified in the ASB: Before further flight, repair per the ASB. \n\n\t(3) If any cracking is found during any inspection specified in paragraph (m) of this AD that is outside the limits specified by the ASB and the ASB specifies to contact Boeing for appropriate action: Before further flight, repair per a method approved by the Manager, Seattle ACO, FAA; or per data meeting the type certification basis of the airplane approved by a Boeing DER who has been authorized by the Manager, Seattle ACO, to make such findings; or by an AR 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 approval must specifically reference this AD. \n\nDetailed Inspections of the Mid-Bulkhead \n\n\t(n) For all airplanes: Prior to the accumulation of 8,000 total flight cycles, or within 90 days after March 15, 2005, whichever occurs later, perform a detailed inspection for cracking of the entire mid-bulkhead, in accordance with the Accomplishment Instructions of Boeing SB 757-54A0039, Revision 3, dated January 13, 2005. \n\n\t(1) If no cracking is detected, repeat the inspection thereafter at intervals not to exceed 3,000 flight cycles. \n\n\t(2) If any cracking is detected, before further flight, repair in accordance with a method approved by the Manager, Seattle ACO, FAA; or according to data meeting the certification basis of the airplane approved by an AR 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 approval must specifically reference this AD. Thereafter, repeat the inspection at intervals not to exceed 3,000 flight cycles. \n\nInspections for Migration of Shims for Certain Airplanes \n\n\t(o) For Group 3 airplanes, as identified in Boeing SB 757- 54A0039, Revision 3, dated January 13, 2005: Within 90 days after March 15, 2005, perform a detailed inspection to detect horizontal or vertical movement of the shims at the joint of the mid-bulkhead and the upper link fittings; in accordance with the Accomplishment Instructions of the SB. If the total shim migration is 0.3 inch or less, repeat the inspection thereafter at intervals not to exceed 3,000 flight cycles. Accomplishment of paragraphs (l) and (m) of this AD constitute terminating action for the requirements of this paragraph, if accomplished prior to March 15, 2005. \n\nInspections for Migration of Shims for Certain Other Airplanes \n\n\t(p) For Groups 1 and 2 airplanes, as identified in Boeing SB 757-54A0039, Revision 3, dated January 13, 2005: If the total shim migration was 0.3 inch or less at the last inspection performed in accordance with paragraph (g)(1) of this AD, within 3,000 flight cycles after the last inspection performed, or within 90 days after March 15, 2005, whichever occurs later, perform the next shim migration inspection in accordance with the Accomplishment Instructions of Revision 3 of the SB. Thereafter, repeat the inspection at intervals not to exceed 3,000 flight cycles. Accomplishment of the initial inspection in accordance with Revision 3 terminates the requirements of paragraphs (g) and (h) of this AD. Accomplishment of paragraphs (l) and (m) of this AD constitute terminating action for the requirements of this paragraph, if accomplished prior to March 15, 2005. \n\nFor Shim Migration That Is More Than 0.3 Inch \n\n\t(q) For Groups 1, 2, and 3 airplanes, as identified in Boeing SB 757-54A0039, Revision 3, dated January 13, 2005: If any total shim migration is more than 0.30 inch, prior to further flight or within 90 days after March 15, 2005, whichever occurs later, perform the actions specified in paragraphs (t) and (u) of this AD. Accomplishment of paragraphs (l) and (m) of this AD constitute terminating action for the requirements of this paragraph, if accomplished prior to March 15, 2005. \n\n\tNote 2: 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 to ensure 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\nInspection of Lower Mid-Spar Bolts \n\n\t(r) For Groups 1, 2, and 3 airplanes, identified in Boeing SB 757-54A0039, Revision 3, dated January 13, 2005: Within 90 days after March 15, 2005, or within 3,000 flight cycles after the last inspection of the lower mid-spar bolts required by paragraph (j) of this AD, whichever occurs later, perform a detailed inspection for cracking around the four bolt heads, nuts, washers, and radius fillers specified in Figure 9 or 17 of the Accomplishment Instructions of Boeing SB 757-54A0039, Revision 3, dated January 13, 2005. Accomplishing the initial detailed inspection ends therepetitive detailed inspection requirements of paragraph (j)(1) this AD. \n\n\t(1) If no cracking is found, repeat the detailed inspection at intervals not to exceed 3,000 flight cycles. \n\n\t(2) If any cracking is found, before further flight, repair per a method approved by the Manager, Seattle ACO, FAA; or per data meeting the type certification basis of the airplane approved by an AR for the Boeing DOA Organization who has been authorized by the Manager, Seattle ACO, to make such findings. For a repair method to be approved, the approval must specifically reference this AD. Thereafter, repeat the inspection at intervals not to exceed 3,000 flight cycles. \n\nTerminating Action for Certain Requirements \n\n\t(s) For Groups 1, 2, and 3 airplanes, identified in Boeing SB 757-54A0039, Revision 3, dated January 13, 2005: Accomplishment of paragraphs (t) and (u) of this AD constitutes terminating action for the repetitive inspections of paragraphs (g)(1), (h)(1), (o), (p), and (r)(1) of this AD. \n\nReplacement of Shims and Sleevebolts \n\n\t(t) For Groups 1, 2, and 3 airplanes, identified in Boeing SB 757-54A0039, Revision 3, dated January 13, 2005: Replace all laminated shims with solid shims; replace existing sleevebolts with new, oversized sleevebolts; and perform a general visual and HFEC inspection to detect cracking and deformation in the sleevebolt holes and in the fittings; as specified in Part II of the Accomplishment Instructions of Boeing SB 757-54A0039, Revision 3, dated January 13, 2005. If any shim cannot be removed, or if any cracking or deformation is found: Before further flight, repair in accordance with a method approved by the Manager, Seattle ACO, FAA; or according to data meeting the certification basis of the airplane approved by an AR 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 approval must specifically reference this AD. \n\nOne-Time HFEC Inspection \n\n\t(u) For Groups 1, 2, and 3, as identified in Boeing SB 757- 54A0039, Revision 3, dated January 13, 2005: Perform a one-time HFEC inspection for cracking in and around the bolt holes of the right and left side of the mid-bulkhead lower flanges, in accordance with Part III of the Accomplishment Instructions of Boeing SB 757- 54A0039, Revision 3, dated January 13, 2005. \n\n\t(1) If no cracking is found: Before further flight, install oversized bolts per Figure 10 of the SB. \n\n\t(2) If any cracking is found that is within the limits of the SB: Before further flight, repair per the SB. \n\n\t(3) If any cracking is found that is outside the limits of the SB and the SB specifies to contact Boeing for appropriate action: Before further flight, repair in accordance with a method approved by the Manager, Seattle ACO, FAA; or according to data meeting the certification basis of the airplane approved by an AR 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 approval must specifically reference this AD. \n\nAlternative Methods of Compliance (AMOCs) \n\n\t(v)(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) 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 AR 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 approval must specifically reference this AD. \n\nMaterial Incorporated by Reference \n\n\t(w) You must use Boeing Alert Service Bulletin 757-54A0039, Revision 1, dated June 20, 2002; Boeing Service Bulletin 757- 54A0039, Revision 2, dated December 2, 2004; or Boeing Service Bulletin 757-54A0039, Revision 3, dated January 13, 2005; to perform the actions that are required by this AD, unless the AD specifies otherwise. \n\n\t(1) On March 15, 2005 (70 FR 9511, February 28, 2005), the Director of the Federal Register approved the incorporation by reference of Boeing Service Bulletin 757-54A0039, Revision 2, dated December 2, 2004; and Boeing Service Bulletin 757-54A0039, Revision 3, dated January 13, 2005. \n\n\t(2) On April 18, 2003 (68 FR 16200, April 3, 2003), the Director of the Federal Register approved the incorporation by reference of Boeing Alert Service Bulletin 757-54A0039, Revision 1, dated June 20, 2002. \n\n\t(3) Contact Boeing Commercial Airplanes, P.O. Box 3707, Seattle, Washington 98124-2207, for a copy of this service information. You may review copies at the Docket Management Facility, U.S. Department of Transportation, 400 Seventh Street, SW., Room PL-401, Nassif Building, Washington, DC; on the Internet at http://dms.dot.gov; 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.

Discussion \n\n\tOn February 14, 2005, we issued AD 2005-04-14, amendment 39-13986 (70 FR 9511, February 28, 2005). That AD applies to certain Boeing Model 757-200, 757-200CB, and 757-200PF series airplanes. That AD requires repetitive detailed inspections to detect horizontal or vertical movement of the shims at the joint of the mid-bulkhead and the upper link fittings; repetitive detailed inspections for cracking of the mid-bulkhead; and corrective action if necessary. That AD also provides optional terminating action for the repetitive inspections. That AD resulted from reports of cracks in the mid-bulkhead lower vertical flange common to the lower chord and stiffener and reports of cracking at other locations on the mid-bulkhead. The actions specified in that AD are intended to detect and correct migration of shims at the joint of the mid-bulkhead and the upper link fittings and cracking of the mid-bulkhead, which could result in cracking of the strutand consequent loss of the strut and engine. \n\nComments \n\n\tWe provided the public the opportunity to submit any relevant written data, views, or arguments about AD 2005-04-14. We have considered the comments received. We have revised AD 2005-04-14 based on the following comments: \n\nRequests To Clarify Terminating Actions \n\n\tOne commenter, the airplane manufacturer, requests that paragraph (k) of AD 2005-04-14 be revised to clarify that accomplishing the optional one-time high frequency eddy current (HFEC) inspection specified only in paragraph (m) ends the repetitive inspections required by paragraph (j)(1). The commenter notes that those repetitive inspections are only applicable to airplanes on which the actions specified in Boeing Alert Service Bulletin (ASB) 757-54A0039, dated November 2, 2000, have been accomplished prior to April 18, 2003. The commenter states that operators of those airplanes have already done the shim replacement specified in paragraph (l), making thataction redundant. \n\n\tWe agree and have revised paragraph (k) of AD 2005-04-14 in this AD accordingly. \n\n\tThe same commenter also requests that paragraphs (k) and (s) of AD 2005-04-14 be revised to clarify that accomplishing the optional one- time HFEC inspection specified in paragraphs (m) and (u), as applicable, ends the repetitive detailed inspections required by paragraph (r)(1). The commenter notes that, in paragraph (k), similar repetitive detailed inspections required by paragraph (j)(1) are terminated by accomplishing the optional actions specified in paragraphs (l) and (m). The commenter also states that the optional one-time HFEC inspection in paragraph (m) is equivalent to that in paragraph (u). \n\n\tWe partially agree. We agree with the commenter that paragraphs (k) and (s) need to be revised. However, we do not agree with the commenter that accomplishing the actions specified only in paragraphs (m) and (u), as applicable, ends the repetitive inspection in paragraph (r)(1). We have determined that accomplishing the optional terminating actions specified in both paragraphs (l) and (m) and both paragraphs (t) and (u), as applicable, are necessary to end the repetitive detailed inspections in paragraph (r)(1). We have revised paragraphs (k) and (s) of AD 2005-04-14 in this AD accordingly. \n\n\tAnother commenter requests that AD 2005-04-14 be revised to clarify that accomplishing the initial detailed inspection required by paragraph (r) ends the repetitive detailed inspections required by paragraph (j)(1). The commenter believes that the detailed inspections in paragraph (r) are redundant to those in paragraph (j). The commenter states that the detailed inspections required by paragraph (r) seem inconsistent with the explanation in "Differences Between the AD and the Service Information" section of AD 2005-04-14. That section states, "(The FAA has) determined that, for airplanes on which the actions specified in Parts I and II of the Accomplishment Instructions of Boeing Alert SB 757-54A0039, dated November 2, 2000, have been accomplished previously, a detailed inspection for cracking, and repair if necessary, within 90 days of the effective date of this AD, and repetitive detailed inspections, are adequate to continue to provide an acceptable level of safety for this interim action." The commenter further states that paragraph (r) requires a detailed inspection of all airplanes, including those on which the optional one-time HFEC inspection specified in paragraph (m) or (u) has been previously done. \n\n\tWe agree with the commenter that clarification is necessary. The detailed inspections required by paragraphs (j) and (r) of AD 2005-04- 14 are identical. The affected airplanes of those two paragraphs are different; however, there is some overlap in the affected airplanes. Paragraph (r), which is applicable to "Groups 1, 2, and 3 airplanes, identified in Boeing Service Bulletin 757-54A0039, Revision 3, dated January 13, 2005," includes all airplanes specified in paragraph (j) (i.e., airplanes on which the actions specified in Boeing ASB 757- 54A0039, dated November 2, 2000, have been accomplished prior to April 18, 2003). It was our intent that, after accomplishing the initial detailed inspection required by paragraph (r) at the new compliance time, the repetitive detailed inspections required by paragraph (j)(1) end for affected airplanes. Therefore, we have revised paragraph (r) of this AD to clarify this point. \n\n\tIn addition, our intent in the "Difference Between the AD and the Service Information" section of AD 2005-04-14 was to point out that referenced Boeing ASB 757-54A0039 recommended a one-time non- destructive test and/or HFEC inspection whereas the AD required repetitive detailed inspections. As discussed in that AD, we determined that the repetitive detailed inspections were adequate to continue to provide an acceptable level of safety for the interim. That section does not reappear in this AD. Therefore, no change to this AD is necessary in this regard. \n\nRequest To Refer to Additional Figure \n\n\tOne commenter requests that the last sentence in paragraph (r) be revised to "* * * perform a detailed inspection for cracking around the four Lower Mid-Spar Bolts as shown in Figure 9 or Figure 17 of SB 757-54A0039, Revision 3, dated January 13, 2005." The commenter believes that, like Figure 9, Figure 17 "Mid-Bulkhead Inspection" in Revision 3 of Boeing Service Bulletin 757-54A0039 also addresses the areas around the four lower mid-spar bolts. The commenter states that Figure 17 provides pictorial views of the subject two front and two rear lower mid-bulkhead bolts whereas Figure 9 shows a sectional view of the area only. \n\n\tWe partially agree. We agree with the commenter to revise paragraph (r) to refer to Figure 17 as an alternative figure for accomplishing the required detailed inspection, but do not agree with the commenter's revised description of the area. We find that "around the four bolt heads, nuts, washer, and radius fillers" is more descriptive of the required inspection area. Therefore, we have revised paragraph (r) to state, "* * * perform a detailed inspection * * * specified in Figure 9 or 17 of the Accomplishment Instructions of Boeing SB 757-54A0039, Revision 3, dated January 13, 2005." \n\nFAA's Determination and Requirements of This AD \n\n\tThe unsafe condition described previously is likely to exist or develop on other airplanes of the same type design. For this reason, we are issuing this AD to revise AD 2005-04-14. This new AD continues to require repetitive detailed inspections to detect horizontal or vertical movement of the shims at the joint of the mid-bulkhead and the upper link fittings; repetitive detailed inspections for cracking of the mid-bulkhead; and corrective action if necessary. This new AD also continues to provide optional terminating actions for certain repetitive inspections. This new AD also clarifies certain terminating actions. \n\nInterim Action \n\n\tThis is considered to be interim action. We are currently considering requiring HFEC inspections for cracking in and around the bolt holes of the left and right side of the mid-bulkhead strut, and repair if necessary. However, the planned compliance time for the HFEC inspections in this AD "is sufficiently long so that notice and opportunity for prior public comment will be practicable." \n\nFAA's Determination of the Effective Date \n\n\tAn unsafe condition exists that requires the immediate adoption of this AD; therefore, providing notice and opportunity for public comment before the AD is issued is impracticable, and good cause exists to make this AD effective in less than 30 days. \n\nComments Invited \n\n\tThis AD is a final rule that involves requirements that affect flight safety and was not preceded by notice and an opportunity for public comment; however, we invite you to submit any relevant written data, views, or arguments regarding this AD.Send your comments to the address listed under the ADDRESSES section. Include "Docket No. FAA- 2005-22054; Directorate Identifier 2005-NM-137-AD" at the beginning of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of the AD that might suggest a need to modify it. \n\n\tWe will post all comments we receive, without change, to http://dms.dot.gov , including any personal information you provide. We will also post a report summarizing each substantive verbal contact with FAA personnel concerning this AD. Using the search function of that Web site, anyone can find and read the comments in any of our dockets, including the name of the individual who sent the comment (or signed the comment on behalf of an association, business, labor union, etc.). You may review the DOT's complete Privacy Act Statement in the Federal Register published on April 11, 2000 (65 FR 19477-78), or you may visit http://dms.dot.gov. \n\nExamining the Dockets \n\n\tYou may examine the AD docket on the Internet at http://dms.dot.gov , or in person at the Docket Management Facility office between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The Docket Management Facility office (telephone (800) 647- 5227) is located on the plaza level of the Nassif Building at the DOT street address stated in the ADDRESSES section. Comments will be available in the AD docket shortly after the Docket Management System receives them. \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\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 the regulation: \n\n\t1. Is not a "significant regulatory action" under Executive Order 12866; \n\n\t2. Is not a "significant rule" under the DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and \n\n\t3. Will nothave 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 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. The Federal Aviation Administration (FAA) amends Sec. 39.13 by removing amendment 39-13986 (70 FR 9511, February 28, 2005) and addingthe following new airworthiness directive (AD):