Airworthiness Directives; The Boeing Company Airplanes, 43178-43181 [2012-17968]

Download as PDF 43178 Federal Register / Vol. 77, No. 142 / Tuesday, July 24, 2012 / Proposed Rules Technical Help Desk, 123 Garratt Boulevard, Toronto, Ontario M3K 1Y5, Canada; telephone 416–375–4000; fax 416–375–4539; email thd.qseries@aero.bombardier.com; Internet http://www.bombardier.com. You may review copies of the referenced service information at the FAA, Transport Airplane Directorate, 1601 Lind Avenue SW., Renton, Washington. For information on the availability of this material at the FAA, call 425–227–1221. Issued in Renton, Washington, on July 13, 2012. Michael Kaszycki, Acting Manager, Transport Airplane Directorate, Aircraft Certification Service. [FR Doc. 2012–17967 Filed 7–23–12; 8:45 am] BILLING CODE 4910–13–P DEPARTMENT OF TRANSPORTATION Federal Aviation Administration 14 CFR Part 39 [Docket No. FAA–2011–0652; Directorate Identifier 2010–NM–045–AD] RIN 2120–AA64 Airworthiness Directives; The Boeing Company Airplanes Federal Aviation Administration (FAA), DOT. ACTION: Supplemental Notice of Proposed Rulemaking (NPRM); reopening of comment period. AGENCY: We are revising an earlier proposed airworthiness directive (AD) for all The Boeing Company Model MD– 90–30 airplanes. That NPRM proposed to require repetitive eddy current high frequency (ETHF) inspections for cracking on the aft side of the left and right wing rear spar lower caps at station Xrs = 164.000, further ETHF inspections if cracks are found, and repair if necessary. The NPRM also proposed repetitive post-repair inspections, and repair if necessary. That NPRM was prompted by reports of cracks of the wing rear spar lower cap at the outboard flap, inboard drive hinge at station Xrs=164.000. This action revises that NPRM by adding repetitive post-repair inspections, and corrective action if necessary. We are proposing this supplemental NPRM to detect and correct cracking of the left and right rear spar lower caps, which could result in fuel leaks and damage to the wing skin or other structure, and consequent loss of the structural integrity of the wing. Since these actions impose an additional burden over that proposed in the NPRM, we are reopening the comment period to allow the public the chance to comment on these proposed changes. Emcdonald on DSK67QTVN1PROD with PROPOSALS SUMMARY: VerDate Mar<15>2010 15:27 Jul 23, 2012 Jkt 226001 We must receive comments on this supplemental NPRM by September 7, 2012. ADDRESSES: You may send comments, using the procedures found in 14 CFR 11.43 and 11.45, by any of the following methods: • Federal eRulemaking Portal: Go to http://www.regulations.gov. Follow the instructions for submitting comments. • Fax: 202–493–2251. • Mail: U.S. Department of Transportation, Docket Operations, M– 30, West Building Ground Floor, Room W12–140, 1200 New Jersey Avenue SE., Washington, DC 20590. • Hand Delivery: U.S. Department of Transportation, Docket Operations, M– 30, West Building Ground Floor, Room W12–140, 1200 New Jersey Avenue SE., Washington, DC 20590, between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. For service information identified in this AD, contact Boeing Commercial Airplanes, Attention: Data & Services Management, 3855 Lakewood Boulevard, MC D800–0019, Long Beach, California 90846–0001; telephone 206– 544–5000, extension 2; fax 206–766– 5683; Internet https:// www.myboeingfleet.com. You may review copies of the referenced service information at the FAA, Transport Airplane Directorate, 1601 Lind Avenue SW., Renton, Washington. For information on the availability of this material at the FAA, call 425–227–1221. DATES: Examining the AD Docket You may examine the AD docket on the Internet at http:// www.regulations.gov; or in person at the Docket Management Facility between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD docket contains this proposed AD, the regulatory evaluation, any comments received, and other information. The street address for the Docket Office (phone: 800–647–5527) is in the ADDRESSES section. Comments will be available in the AD docket shortly after receipt. FOR FURTHER INFORMATION CONTACT: Roger Durbin, Airframe Branch, ANM– 120L, FAA, Los Angeles Aircraft Certification Office (ACO), 3960 Paramount Boulevard, Lakewood, California 90712–4137; phone (562) 627–5233; fax (562) 627–5210; email: roger.durbin@faa.gov. SUPPLEMENTARY INFORMATION: Comments Invited We invite you to send any written relevant data, views, or arguments about this proposed AD. Send your comments PO 00000 Frm 00003 Fmt 4702 Sfmt 4702 to an address listed under the ADDRESSES section. Include ‘‘Docket No. FAA–2011–0652; Directorate Identifier 2010–NM–045–AD’’ at the beginning of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of this proposed AD. We will consider all comments received by the closing date and may amend this proposed AD because of those comments. We will post all comments we receive, without change, to http:// www.regulations.gov, including any personal information you provide. We will also post a report summarizing each substantive verbal contact we receive about this proposed AD. Discussion We issued an NPRM to amend 14 CFR part 39 to include an AD that would apply to all The Boeing Company Model MD–90–30 airplanes. That NPRM published in the Federal Register on July 8, 2011 (76 FR 40288). That NPRM proposed to require repetitive eddy current high frequency (ETHF) inspections for cracking on the aft side of the left and right wing rear spar lower caps at station Xrs=164.000, further ETHF inspections if cracks are found, and repair if necessary. The NPRM also proposed repetitive post-repair inspections, and repair if necessary. Actions Since Previous NPRM (76 FR 40288, July 8, 2011) Was Issued Since we issued the previous NPRM (76 FR 40288, July 8, 2011), we have determined that it is necessary to add repetitive inspections for cracking on the wing rear spar lower caps at station Xrs=164.000 after the splice repair is done. The replacement spar cap is susceptible to fatigue cracking because its design is the same as that of the original spar cap. Comments We gave the public the opportunity to comment on the previous NPRM (76 FR 40288, July 8, 2011). The following presents the comments received on the NPRM and the FAA’s response to each comment. Request for Inspection Boeing requested that we revise the original NPRM (76 FR 40288, July 8, 2011) to require an ETHF inspection on any splice repair within 30,000 flight cycles after the repair. Boeing explained that neither Boeing Alert Service Bulletin MD90–57A026, Revision 1, dated February 23, 2011 (which was cited as the appropriate source of service information for the original E:\FR\FM\24JYP1.SGM 24JYP1 Federal Register / Vol. 77, No. 142 / Tuesday, July 24, 2012 / Proposed Rules NPRM), nor the original NPRM itself addresses inspection of the replaced spar cap segment for fatigue cracking at flap hinge station Xrs=164.000. Boeing noted that the design of the original and replacement spar caps is the same, so the replacement spar cap is also susceptible to the same fatigue cracking issue. Boeing suggested that this change would affect paragraphs (h)(1)(ii), (h)(2)(ii), (h)(3)(ii), (i)(1), (i)(2)(i)(C), (i)(2)(ii), and (i)(3) of the original NPRM. Boeing also explained that they will revise Boeing Alert Service Bulletin MD90–57A026, Revision 1, dated February 23, 2011, as soon as possible. We agree with the request, for the reasons provided by the commenter. We have added this post-repair inspection in new paragraph (j) of this AD, and reidentified subsequent paragraphs accordingly. FAA’s Determination We are proposing this supplemental NPRM because we evaluated all the relevant information and determined the unsafe condition described previously is likely to exist or develop in other products of the same type design. Certain changes described above expand the scope of the original NPRM (76 FR 40288, July 8, 2011). As a result, we have determined that it is necessary to reopen the comment period to provide additional opportunity for the public to comment on this supplemental NPRM. Proposed Requirements of the Supplemental NPRM This supplemental NPRM would require accomplishing the actions specified in the service information described previously, except as discussed under ‘‘Differences Between the Supplemental NPRM and the Service Information.’’ 43179 Differences Between the Supplemental NPRM and the Service Information Boeing Alert Service Bulletin MD90– 57A026, Revision 1, dated February 23, 2011, does not specify corrective actions if cracking is found during any inspection of repaired areas, but this proposed AD would require repairing those conditions in one of the following ways: • In accordance with a method that we approve; or • Using data that meet the certification basis of the airplane, and that have been approved by the Boeing Commercial Airplanes Organization Designation Authorization (ODA) whom we have authorized to make those findings. Costs of Compliance We estimate that this proposed AD affects 51 airplanes of U.S. registry. We estimate the following costs to comply with this proposed AD: ESTIMATED COSTS Action Labor cost Parts cost Cost per product Inspection ........................... 4 work-hours × $85 per hour = $340 per inspection cycle. N/A ..................................... $340 per inspection cycle .. Emcdonald on DSK67QTVN1PROD with PROPOSALS We have received no definitive data that would enable us to provide cost estimates for the on-condition actions specified in this AD. Authority for This Rulemaking Title 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. We 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. Regulatory Findings We determined that this proposed AD would not have federalism implications under Executive Order 13132. This VerDate Mar<15>2010 15:27 Jul 23, 2012 Jkt 226001 proposed AD would 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. For the reasons discussed above, I certify this proposed regulation: (1) Is not a ‘‘significant regulatory action’’ under Executive Order 12866, (2) Is not a ‘‘significant rule’’ under the DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979), (3) Will not affect intrastate aviation in Alaska, and (4) 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. List of Subjects in 14 CFR Part 39 Air transportation, Aircraft, Aviation safety, Incorporation by reference, Safety. Cost on U.S. operators $17,340 per inspection cycle. PART 39—AIRWORTHINESS DIRECTIVES 1. The authority citation for part 39 continues to read as follows: Authority: 49 U.S.C. 106(g), 40113, 44701. § 39.13 [Amended] 2. The FAA amends § 39.13 by adding the following new airworthiness directive (AD): The Boeing Company: Docket No. FAA– 2011–0652; Directorate Identifier 2010– NM–045–AD. (a) Comments Due Date We must receive comments by September 7, 2012. (b) Affected ADs None. (c) Applicability This AD applies to all The Boeing Company Model MD–90–30 airplanes, certificated in any category. The Proposed Amendment (d) Subject Joint Aircraft System Component (JASC)/ Air Transport Association (ATA) of America Code 57, Wings. Accordingly, under the authority delegated to me by the Administrator, the FAA proposes to amend 14 CFR part 39 as follows: (e) Unsafe Condition This AD was prompted by reports of cracks of the wing rear spar lower cap at the outboard flap, inboard drive hinge at station PO 00000 Frm 00004 Fmt 4702 Sfmt 4702 E:\FR\FM\24JYP1.SGM 24JYP1 43180 Federal Register / Vol. 77, No. 142 / Tuesday, July 24, 2012 / Proposed Rules Xrs=164.000. We are issuing this AD to detect and correct cracking of the left and right rear spar lower caps, which could result in fuel leaks and damage to the wing skin or other structure, and consequent loss of the structural integrity of the wing. (f) Compliance Comply with this AD within the compliance times specified, unless already done. Emcdonald on DSK67QTVN1PROD with PROPOSALS (g) Repetitive Inspections Before the accumulation of 30,000 total flight cycles, or within 10,000 flight cycles after the effective date of this AD, whichever occurs later, do an eddy current high frequency (ETHF) inspection for cracking on the aft side of the left and right wing rear spar lower caps at station Xrs=164.000, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin MD90–57A026, Revision 1, dated February 23, 2011. If no cracking is found on the left or right wing rear spar lower cap, repeat the inspection on the affected wing rear spar lower cap thereafter at intervals not to exceed 2,550 flight cycles. Doing a repair of the left or right wing rear spar lower cap required by this AD terminates the repetitive inspection required by this paragraph for that side only. (h) Further Inspections if Cracking of Two Inches or Less Is Found and Not in the Rear Spar Lower Cap, Repair, and Repetitive Post-Repair Inspections If, during any inspection required by paragraph (g) of this AD, any crack is found that is two inches or less and not in the rear spar lower cap forward horizontal leg radius: Before further flight, do an ETHF inspection for cracking on the affected wing rear spar upper cap at station Xrs = 164.000, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin MD90–57A026, Revision 1, dated February 23, 2011. (1) If no crack is found in the rear spar upper cap during the inspection required in paragraph (h) of this AD, do the actions specified in paragraph (h)(1)(i) or (h)(1)(ii) of this AD. (i) Option 1: Before further flight, do a doubler repair of the rear spar lower cap, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin MD90–57A026, Revision 1, dated February 23, 2011. Within 13,500 flight cycles after doing the doubler repair, do an ETHF inspection for any cracking in the repaired area of the rear spar lower cap, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin MD90–57A026, Revision 1, dated February 23, 2011. Repeat the inspection thereafter at intervals not to exceed 8,500 flight cycles. If any cracking is found during any inspection required by this paragraph, before further flight, repair in accordance with a method approved in accordance with the procedures specified in paragraph (l) of this AD. (ii) Option 2: Before further flight, do a splice repair of the rear spar lower cap, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin MD90–57A026, Revision 1, dated February 23, 2011. Within 20,000 flight cycles after VerDate Mar<15>2010 15:27 Jul 23, 2012 Jkt 226001 doing the splice repair, do an eddy current low frequency (ETLF) inspection and an ultrasonic (UT) inspection for cracking in the repaired area of the rear spar lower cap, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin MD90–57A026, Revision 1, dated February 23, 2011. Repeat the inspections thereafter at intervals not to exceed 3,000 flight cycles. If any cracking is found during any inspection required by this paragraph, before further flight, repair in accordance with a method approved in accordance with the procedures specified in paragraph (l) of this AD. (2) If any crack that is two inches or less is found in the rear spar upper cap during the inspection required by paragraph (h) of this AD, do the actions specified in paragraph (h)(2)(i) or (h)(2)(ii) of this AD. (i) Option 1: Before further flight, do a doubler repair of the rear spar upper and lower caps, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin MD90–57A026, Revision 1, dated February 23, 2011. Within 13,500 flight cycles after doing the doubler repair, do an ETHF inspection for any cracking in the repaired area of the rear spar upper and lower caps, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin MD90–57A026, Revision 1, dated February 23, 2011. Repeat the inspection thereafter at intervals not to exceed 8,500 flight cycles. If any cracking is found during any inspection required by this paragraph, before further flight, repair in accordance with a method approved in accordance with the procedures specified in paragraph (l) of this AD. (ii) Option 2: Before further flight, do a splice repair of the rear spar upper and lower caps, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin MD90–57A026, Revision 1, dated February 23, 2011. Within 20,000 flight cycles after doing the splice repair, do an ETLF inspection and a UT inspection for any cracking in the repaired area of the rear spar lower cap, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin MD90–57A026, Revision 1, dated February 23, 2011. Repeat the inspections thereafter at intervals not to exceed 3,000 flight cycles. If any cracking is found during any inspection required by this paragraph, before further flight, repair in accordance with a method approved in accordance with the procedures specified in paragraph (l) of this AD. (3) If any crack that is greater than two inches is found in the rear spar upper cap during the inspection required by paragraph (h) of this AD, do the actions specified in paragraph (h)(3)(i) or (h)(3)(ii) of this AD. (i) Option 1: Before further flight, do a splice repair of the rear spar upper cap and a doubler repair of the rear spar lower cap, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin MD90–57A026, Revision 1, dated February 23, 2011. Within 13,500 flight cycles after doing the doubler repair, do an ETHF inspection for any cracking in the repaired area of the rear spar lower cap, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin MD90–57A026, PO 00000 Frm 00005 Fmt 4702 Sfmt 4702 Revision 1, dated February 23, 2011. Repeat the inspection thereafter at intervals not to exceed 8,500 flight cycles. If any cracking is found during any inspection required by this paragraph, before further flight, repair in accordance with a method approved in accordance with the procedures specified in paragraph (l) of this AD. (ii) Option 2: Before further flight, do a splice repair of the rear spar upper and lower caps, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin MD90–57A026, Revision 1, dated February 23, 2011. Within 20,000 flight cycles after doing the splice repair, do an ETLF inspection and a UT inspection for any cracking in the repaired area of the rear spar lower cap, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin MD90–57A026, Revision 1, dated February 23, 2011. Repeat the inspections thereafter at intervals not to exceed 3,000 flight cycles. If any cracking is found during any inspection required by this paragraph, before further flight, repair in accordance with a method approved in accordance with the procedures specified in paragraph (l) of this AD. (i) Further Inspections if Cracking That Is Greater Than Two Inches Is Found or Is in the Rear Spar Lower Cap, Repair, and Repetitive Post-Repair Inspections If, during any inspection required by paragraph (g) of this AD, any crack is found that is greater than two inches or is in the rear spar lower cap forward horizontal leg radius, before further flight, do an ETHF inspection for cracking on the affected wing rear spar upper cap at station Xrs = 164.000, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin MD90–57A026, Revision 1, dated February 23, 2011. (1) If no crack is found in the rear spar upper cap, before further flight, do a splice repair of the rear spar lower cap, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin MD90–57A026, Revision 1, dated February 23, 2011. Within 20,000 flight cycles after doing the splice repair, do an ETLF inspection and a UT inspection for any cracking of the repaired area of the lower rear spar cap, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin MD90–57A026, Revision 1, dated February 23, 2011. Repeat the inspections thereafter at intervals not to exceed 3,000 flight cycles. If any cracking is found during any inspection required by this paragraph, before further flight, repair in accordance with a method approved in accordance with the procedures specified in paragraph (l) of this AD. (2) If any crack that is two inches or less is found in the rear spar upper cap, do the actions specified in paragraph (i)(2)(i) or (i)(2)(ii) of this AD. (i) Option 1: Do the actions specified in paragraphs (i)(2)(i)(A), (i)(2)(i)(B), and (i)(2)(i)(C) of this AD. (A) Before further flight, do a doubler repair of the rear spar upper cap and a splice repair of the rear spar lower cap, in accordance with the Accomplishment E:\FR\FM\24JYP1.SGM 24JYP1 Emcdonald on DSK67QTVN1PROD with PROPOSALS Federal Register / Vol. 77, No. 142 / Tuesday, July 24, 2012 / Proposed Rules Instructions of Boeing Alert Service Bulletin MD90–57A026, Revision 1, dated February 23, 2011. (B) Within 13,500 flight cycles after doing the doubler repair required by paragraph (i)(2)(i)(A) of this AD, do an ETHF inspection for any cracking in the repaired area of the rear spar upper cap, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin MD90–57A026, Revision 1, dated February 23, 2011. Repeat the inspection thereafter at intervals not to exceed 8,500 flight cycles. If any cracking is found during any inspection required by this paragraph, before further flight, repair in accordance with a method approved in accordance with the procedures specified in paragraph (l) of this AD. (C) Within 20,000 flight cycles after doing the splice repair required by paragraph (i)(2)(i)(A) of this AD, do an ETLF inspection and a UT inspection for cracking in the repaired area of the rear spar lower cap, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin MD90–57A026, Revision 1, dated February 23, 2011. Repeat the inspections thereafter at intervals not to exceed 3,000 flight cycles. If any cracking is found during any inspection required by this paragraph, before further flight, repair in accordance with a method approved in accordance with the procedures specified in paragraph (l) of this AD. (ii) Option 2: Before further flight, do a splice repair of the rear spar upper and lower caps, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin MD90–57A026, Revision 1, dated February 23, 2011. Within 20,000 flight cycles after doing the splice repair, do an ETLF inspection and a UT inspection for cracking in the repaired area of the rear spar lower cap, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin MD90–57A026, Revision 1, dated February 23, 2011. Repeat the inspections thereafter at intervals not to exceed 3,000 flight cycles. If any cracking is found during any inspection required by this paragraph, before further flight, repair in accordance with a method approved in accordance with the procedures specified in paragraph (l) of this AD. (3) If any crack that is greater than two inches is found in the rear spar upper cap, before further flight, do a splice repair of the rear spar upper and lower caps, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin MD90–57A026, Revision 1, dated February 23, 2011. Within 20,000 flight cycles after doing the splice repair, do an ETLF inspection and a UT inspection for cracking in the repaired area of the rear spar lower cap, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin MD90–57A026, Revision 1, dated February 23, 2011. Repeat the inspections thereafter at intervals not to exceed 3,000 flight cycles. If any cracking is found during any inspection required by this paragraph, before further flight, repair in accordance with a method approved in accordance with the procedures specified in paragraph (l) of this AD. VerDate Mar<15>2010 15:27 Jul 23, 2012 Jkt 226001 (j) Repeat ETHF Inspection For airplanes on which any splice repair was required by this AD: Within 30,000 flight cycles after the splice repair, repeat the inspection required by paragraph (g) of this AD for the repaired wing. If no cracking is found on the on the rear spar lower cap of the repaired wing, repeat the inspection on the affected wing rear spar lower cap thereafter at intervals not to exceed 2,550 flight cycles. If any cracking is found during any inspection required by this paragraph, before further flight, repair in accordance with a method approved in accordance with the procedures specified in paragraph (l) of this AD. (k) Credit for Previous Actions This paragraph provides credit for the actions required by paragraphs (g), (h), and (i) of this AD, if those actions were performed before the effective date of this AD using Boeing Alert Service Bulletin MD90–57A026, dated February 11, 2010. (l) Alternative Methods of Compliance (AMOCs) (1) The Manager, Los Angeles Aircraft Certification Office (ACO), FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. In accordance with 14 CFR 39.19, send your request to your principal inspector or local Flight Standards District Office, as appropriate. If sending information directly to the manager of the ACO, send it to the attention of the person identified in the Related Information section of this AD. (2) Before using any approved AMOC, notify your appropriate principal inspector, or lacking a principal inspector, the manager of the local flight standards district office/ certificate holding district office. (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 the Boeing Commercial Airplanes Organization Designation Authorization (ODA) that 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. (m) Related Information (1) For more information about this AD, contact Roger Durbin, Airframe Branch, ANM–120L, FAA, Los Angeles ACO, 3960 Paramount Boulevard, Lakewood, California 90712–4137; phone: (562) 627–5233; fax: (562) 627–5210; email: roger.durbin@faa.gov. (2) For service information identified in this AD, contact Boeing Commercial Airplanes, Attention: Data & Services Management, 3855 Lakewood Boulevard, MC D800–0019, Long Beach, California 90846– 0001; telephone 206–544–5000, extension 2; fax 206–766–5683; Internet https:// www.myboeingfleet.com. You may review copies of the referenced service information at the FAA, Transport Airplane Directorate, 1601 Lind Avenue SW., Renton, Washington. For information on the availability of this material at the FAA, call 425–227–1221. PO 00000 Frm 00006 Fmt 4702 Sfmt 4702 43181 Issued in Renton, Washington, on July 13, 2012. Michael Kaszycki, Acting Manager, Transport Airplane Directorate, Aircraft Certification Service. [FR Doc. 2012–17968 Filed 7–23–12; 8:45 am] BILLING CODE 4910–13–P DEPARTMENT OF TRANSPORTATION Federal Aviation Administration 14 CFR Part 71 Docket No. FAA–2012–0705; Airspace Docket No. 12–AWP–4 Proposed Establishment of Class E Airspace; Coaldale, NV Federal Aviation Administration (FAA), DOT. ACTION: Notice of proposed rulemaking (NPRM). AGENCY: This action proposes to establish Class E airspace at Coaldale VHF Omni-Directional Radio Range Tactical Air Navigational Aid (VORTAC), Coaldale, NV to facilitate vectoring of Instrument Flight Rules (IFR) aircraft under control of Oakland Air Route Traffic Control Center (ARTCC). The FAA is proposing this action to enhance the safety and management of aircraft operations within the National Airspace System. DATES: Comments must be received on or before September 7, 2012. ADDRESSES: Send comments on this proposal to the U.S. Department of Transportation, Docket Operations, M– 30, West Building Ground Floor, Room W12–140, 1200 New Jersey Avenue SE., Washington, DC 20590; telephone (202) 366–9826. You must identify FAA Docket No. FAA–2012–0705; Airspace Docket No. 12–AWP–4, at the beginning of your comments. You may also submit comments through the Internet at http://www.regulations.gov. FOR FURTHER INFORMATION CONTACT: Eldon Taylor, Federal Aviation Administration, Operations Support Group, Western Service Center, 1601 Lind Avenue SW., Renton, WA 98057; telephone (425) 203–4537. SUPPLEMENTARY INFORMATION: SUMMARY: Comments Invited Interested parties are invited to participate in this proposed rulemaking by submitting such written data, views, or arguments, as they may desire. Comments that provide the factual basis supporting the views and suggestions presented are particularly helpful in developing reasoned regulatory E:\FR\FM\24JYP1.SGM 24JYP1

Agencies

[Federal Register Volume 77, Number 142 (Tuesday, July 24, 2012)]
[Proposed Rules]
[Pages 43178-43181]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2012-17968]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2011-0652; Directorate Identifier 2010-NM-045-AD]
RIN 2120-AA64


Airworthiness Directives; The Boeing Company Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Supplemental Notice of Proposed Rulemaking (NPRM); reopening of 
comment period.

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SUMMARY: We are revising an earlier proposed airworthiness directive 
(AD) for all The Boeing Company Model MD-90-30 airplanes. That NPRM 
proposed to require repetitive eddy current high frequency (ETHF) 
inspections for cracking on the aft side of the left and right wing 
rear spar lower caps at station Xrs = 164.000, further ETHF inspections 
if cracks are found, and repair if necessary. The NPRM also proposed 
repetitive post-repair inspections, and repair if necessary. That NPRM 
was prompted by reports of cracks of the wing rear spar lower cap at 
the outboard flap, inboard drive hinge at station Xrs=164.000. This 
action revises that NPRM by adding repetitive post-repair inspections, 
and corrective action if necessary. We are proposing this supplemental 
NPRM to detect and correct cracking of the left and right rear spar 
lower caps, which could result in fuel leaks and damage to the wing 
skin or other structure, and consequent loss of the structural 
integrity of the wing. Since these actions impose an additional burden 
over that proposed in the NPRM, we are reopening the comment period to 
allow the public the chance to comment on these proposed changes.

DATES: We must receive comments on this supplemental NPRM by September 
7, 2012.

ADDRESSES: You may send comments, using the procedures found in 14 CFR 
11.43 and 11.45, by any of the following methods:
     Federal eRulemaking Portal: Go to http://www.regulations.gov. Follow the instructions for submitting comments.
     Fax: 202-493-2251.
     Mail: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue SE., Washington, DC 20590.
     Hand Delivery: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue SE., Washington, DC 20590, between 9 a.m. and 5 p.m., 
Monday through Friday, except Federal holidays.
    For service information identified in this AD, contact Boeing 
Commercial Airplanes, Attention: Data & Services Management, 3855 
Lakewood Boulevard, MC D800-0019, Long Beach, California 90846-0001; 
telephone 206-544-5000, extension 2; fax 206-766-5683; Internet https://www.myboeingfleet.com. You may review copies of the referenced service 
information at the FAA, Transport Airplane Directorate, 1601 Lind 
Avenue SW., Renton, Washington. For information on the availability of 
this material at the FAA, call 425-227-1221.

Examining the AD Docket

    You may examine the AD docket on the Internet at http://www.regulations.gov; or in person at the Docket Management Facility 
between 9 a.m. and 5 p.m., Monday through Friday, except Federal 
holidays. The AD docket contains this proposed AD, the regulatory 
evaluation, any comments received, and other information. The street 
address for the Docket Office (phone: 800-647-5527) is in the ADDRESSES 
section. Comments will be available in the AD docket shortly after 
receipt.

FOR FURTHER INFORMATION CONTACT: Roger Durbin, Airframe Branch, ANM-
120L, FAA, Los Angeles Aircraft Certification Office (ACO), 3960 
Paramount Boulevard, Lakewood, California 90712-4137; phone (562) 627-
5233; fax (562) 627-5210; email: roger.durbin@faa.gov.

SUPPLEMENTARY INFORMATION: 

Comments Invited

    We invite you to send any written relevant data, views, or 
arguments about this proposed AD. Send your comments to an address 
listed under the ADDRESSES section. Include ``Docket No. FAA-2011-0652; 
Directorate Identifier 2010-NM-045-AD'' at the beginning of your 
comments. We specifically invite comments on the overall regulatory, 
economic, environmental, and energy aspects of this proposed AD. We 
will consider all comments received by the closing date and may amend 
this proposed AD because of those comments.
    We will post all comments we receive, without change, to http://www.regulations.gov, including any personal information you provide. We 
will also post a report summarizing each substantive verbal contact we 
receive about this proposed AD.

Discussion

    We issued an NPRM to amend 14 CFR part 39 to include an AD that 
would apply to all The Boeing Company Model MD-90-30 airplanes. That 
NPRM published in the Federal Register on July 8, 2011 (76 FR 40288). 
That NPRM proposed to require repetitive eddy current high frequency 
(ETHF) inspections for cracking on the aft side of the left and right 
wing rear spar lower caps at station Xrs=164.000, further ETHF 
inspections if cracks are found, and repair if necessary. The NPRM also 
proposed repetitive post-repair inspections, and repair if necessary.

Actions Since Previous NPRM (76 FR 40288, July 8, 2011) Was Issued

    Since we issued the previous NPRM (76 FR 40288, July 8, 2011), we 
have determined that it is necessary to add repetitive inspections for 
cracking on the wing rear spar lower caps at station Xrs=164.000 after 
the splice repair is done. The replacement spar cap is susceptible to 
fatigue cracking because its design is the same as that of the original 
spar cap.

Comments

    We gave the public the opportunity to comment on the previous NPRM 
(76 FR 40288, July 8, 2011). The following presents the comments 
received on the NPRM and the FAA's response to each comment.

Request for Inspection

    Boeing requested that we revise the original NPRM (76 FR 40288, 
July 8, 2011) to require an ETHF inspection on any splice repair within 
30,000 flight cycles after the repair. Boeing explained that neither 
Boeing Alert Service Bulletin MD90-57A026, Revision 1, dated February 
23, 2011 (which was cited as the appropriate source of service 
information for the original

[[Page 43179]]

NPRM), nor the original NPRM itself addresses inspection of the 
replaced spar cap segment for fatigue cracking at flap hinge station 
Xrs=164.000. Boeing noted that the design of the original and 
replacement spar caps is the same, so the replacement spar cap is also 
susceptible to the same fatigue cracking issue. Boeing suggested that 
this change would affect paragraphs (h)(1)(ii), (h)(2)(ii), (h)(3)(ii), 
(i)(1), (i)(2)(i)(C), (i)(2)(ii), and (i)(3) of the original NPRM.
    Boeing also explained that they will revise Boeing Alert Service 
Bulletin MD90-57A026, Revision 1, dated February 23, 2011, as soon as 
possible.
    We agree with the request, for the reasons provided by the 
commenter. We have added this post-repair inspection in new paragraph 
(j) of this AD, and re-identified subsequent paragraphs accordingly.

FAA's Determination

    We are proposing this supplemental NPRM because we evaluated all 
the relevant information and determined the unsafe condition described 
previously is likely to exist or develop in other products of the same 
type design. Certain changes described above expand the scope of the 
original NPRM (76 FR 40288, July 8, 2011). As a result, we have 
determined that it is necessary to reopen the comment period to provide 
additional opportunity for the public to comment on this supplemental 
NPRM.

Proposed Requirements of the Supplemental NPRM

    This supplemental NPRM would require accomplishing the actions 
specified in the service information described previously, except as 
discussed under ``Differences Between the Supplemental NPRM and the 
Service Information.''

Differences Between the Supplemental NPRM and the Service Information

    Boeing Alert Service Bulletin MD90-57A026, Revision 1, dated 
February 23, 2011, does not specify corrective actions if cracking is 
found during any inspection of repaired areas, but this proposed AD 
would require repairing those conditions in one of the following ways:
     In accordance with a method that we approve; or
     Using data that meet the certification basis of the 
airplane, and that have been approved by the Boeing Commercial 
Airplanes Organization Designation Authorization (ODA) whom we have 
authorized to make those findings.

Costs of Compliance

    We estimate that this proposed AD affects 51 airplanes of U.S. 
registry. We estimate the following costs to comply with this proposed 
AD:

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                      Cost per
            Action                Labor cost        Parts cost        product          Cost on U.S. operators
----------------------------------------------------------------------------------------------------------------
Inspection...................  4 work-hours x    N/A............  $340 per         $17,340 per inspection cycle.
                                $85 per hour =                     inspection
                                $340 per                           cycle.
                                inspection
                                cycle.
----------------------------------------------------------------------------------------------------------------

    We have received no definitive data that would enable us to provide 
cost estimates for the on-condition actions specified in this AD.

Authority for This Rulemaking

    Title 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.
    We 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.

Regulatory Findings

    We determined that this proposed AD would not have federalism 
implications under Executive Order 13132. This proposed AD would 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.
    For the reasons discussed above, I certify this proposed 
regulation:
    (1) Is not a ``significant regulatory action'' under Executive 
Order 12866,
    (2) Is not a ``significant rule'' under the DOT Regulatory Policies 
and Procedures (44 FR 11034, February 26, 1979),
    (3) Will not affect intrastate aviation in Alaska, and
    (4) 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.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, Safety.

The Proposed Amendment

    Accordingly, under the authority delegated to me by the 
Administrator, the FAA proposes to amend 14 CFR part 39 as follows:

PART 39--AIRWORTHINESS DIRECTIVES

    1. The authority citation for part 39 continues to read as follows:

    Authority:  49 U.S.C. 106(g), 40113, 44701.


Sec.  39.13  [Amended]

    2. The FAA amends Sec.  39.13 by adding the following new 
airworthiness directive (AD):

The Boeing Company: Docket No. FAA-2011-0652; Directorate Identifier 
2010-NM-045-AD.

(a) Comments Due Date

    We must receive comments by September 7, 2012.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to all The Boeing Company Model MD-90-30 
airplanes, certificated in any category.

(d) Subject

    Joint Aircraft System Component (JASC)/Air Transport Association 
(ATA) of America Code 57, Wings.

(e) Unsafe Condition

    This AD was prompted by reports of cracks of the wing rear spar 
lower cap at the outboard flap, inboard drive hinge at station

[[Page 43180]]

Xrs=164.000. We are issuing this AD to detect and correct cracking 
of the left and right rear spar lower caps, which could result in 
fuel leaks and damage to the wing skin or other structure, and 
consequent loss of the structural integrity of the wing.

(f) Compliance

    Comply with this AD within the compliance times specified, 
unless already done.

(g) Repetitive Inspections

    Before the accumulation of 30,000 total flight cycles, or within 
10,000 flight cycles after the effective date of this AD, whichever 
occurs later, do an eddy current high frequency (ETHF) inspection 
for cracking on the aft side of the left and right wing rear spar 
lower caps at station Xrs=164.000, in accordance with the 
Accomplishment Instructions of Boeing Alert Service Bulletin MD90-
57A026, Revision 1, dated February 23, 2011. If no cracking is found 
on the left or right wing rear spar lower cap, repeat the inspection 
on the affected wing rear spar lower cap thereafter at intervals not 
to exceed 2,550 flight cycles. Doing a repair of the left or right 
wing rear spar lower cap required by this AD terminates the 
repetitive inspection required by this paragraph for that side only.

(h) Further Inspections if Cracking of Two Inches or Less Is Found and 
Not in the Rear Spar Lower Cap, Repair, and Repetitive Post-Repair 
Inspections

    If, during any inspection required by paragraph (g) of this AD, 
any crack is found that is two inches or less and not in the rear 
spar lower cap forward horizontal leg radius: Before further flight, 
do an ETHF inspection for cracking on the affected wing rear spar 
upper cap at station Xrs = 164.000, in accordance with the 
Accomplishment Instructions of Boeing Alert Service Bulletin MD90-
57A026, Revision 1, dated February 23, 2011.
    (1) If no crack is found in the rear spar upper cap during the 
inspection required in paragraph (h) of this AD, do the actions 
specified in paragraph (h)(1)(i) or (h)(1)(ii) of this AD.
    (i) Option 1: Before further flight, do a doubler repair of the 
rear spar lower cap, in accordance with the Accomplishment 
Instructions of Boeing Alert Service Bulletin MD90-57A026, Revision 
1, dated February 23, 2011. Within 13,500 flight cycles after doing 
the doubler repair, do an ETHF inspection for any cracking in the 
repaired area of the rear spar lower cap, in accordance with the 
Accomplishment Instructions of Boeing Alert Service Bulletin MD90-
57A026, Revision 1, dated February 23, 2011. Repeat the inspection 
thereafter at intervals not to exceed 8,500 flight cycles. If any 
cracking is found during any inspection required by this paragraph, 
before further flight, repair in accordance with a method approved 
in accordance with the procedures specified in paragraph (l) of this 
AD.
    (ii) Option 2: Before further flight, do a splice repair of the 
rear spar lower cap, in accordance with the Accomplishment 
Instructions of Boeing Alert Service Bulletin MD90-57A026, Revision 
1, dated February 23, 2011. Within 20,000 flight cycles after doing 
the splice repair, do an eddy current low frequency (ETLF) 
inspection and an ultrasonic (UT) inspection for cracking in the 
repaired area of the rear spar lower cap, in accordance with the 
Accomplishment Instructions of Boeing Alert Service Bulletin MD90-
57A026, Revision 1, dated February 23, 2011. Repeat the inspections 
thereafter at intervals not to exceed 3,000 flight cycles. If any 
cracking is found during any inspection required by this paragraph, 
before further flight, repair in accordance with a method approved 
in accordance with the procedures specified in paragraph (l) of this 
AD.
    (2) If any crack that is two inches or less is found in the rear 
spar upper cap during the inspection required by paragraph (h) of 
this AD, do the actions specified in paragraph (h)(2)(i) or 
(h)(2)(ii) of this AD.
    (i) Option 1: Before further flight, do a doubler repair of the 
rear spar upper and lower caps, in accordance with the 
Accomplishment Instructions of Boeing Alert Service Bulletin MD90-
57A026, Revision 1, dated February 23, 2011. Within 13,500 flight 
cycles after doing the doubler repair, do an ETHF inspection for any 
cracking in the repaired area of the rear spar upper and lower caps, 
in accordance with the Accomplishment Instructions of Boeing Alert 
Service Bulletin MD90-57A026, Revision 1, dated February 23, 2011. 
Repeat the inspection thereafter at intervals not to exceed 8,500 
flight cycles. If any cracking is found during any inspection 
required by this paragraph, before further flight, repair in 
accordance with a method approved in accordance with the procedures 
specified in paragraph (l) of this AD.
    (ii) Option 2: Before further flight, do a splice repair of the 
rear spar upper and lower caps, in accordance with the 
Accomplishment Instructions of Boeing Alert Service Bulletin MD90-
57A026, Revision 1, dated February 23, 2011. Within 20,000 flight 
cycles after doing the splice repair, do an ETLF inspection and a UT 
inspection for any cracking in the repaired area of the rear spar 
lower cap, in accordance with the Accomplishment Instructions of 
Boeing Alert Service Bulletin MD90-57A026, Revision 1, dated 
February 23, 2011. Repeat the inspections thereafter at intervals 
not to exceed 3,000 flight cycles. If any cracking is found during 
any inspection required by this paragraph, before further flight, 
repair in accordance with a method approved in accordance with the 
procedures specified in paragraph (l) of this AD.
    (3) If any crack that is greater than two inches is found in the 
rear spar upper cap during the inspection required by paragraph (h) 
of this AD, do the actions specified in paragraph (h)(3)(i) or 
(h)(3)(ii) of this AD.
    (i) Option 1: Before further flight, do a splice repair of the 
rear spar upper cap and a doubler repair of the rear spar lower cap, 
in accordance with the Accomplishment Instructions of Boeing Alert 
Service Bulletin MD90-57A026, Revision 1, dated February 23, 2011. 
Within 13,500 flight cycles after doing the doubler repair, do an 
ETHF inspection for any cracking in the repaired area of the rear 
spar lower cap, in accordance with the Accomplishment Instructions 
of Boeing Alert Service Bulletin MD90-57A026, Revision 1, dated 
February 23, 2011. Repeat the inspection thereafter at intervals not 
to exceed 8,500 flight cycles. If any cracking is found during any 
inspection required by this paragraph, before further flight, repair 
in accordance with a method approved in accordance with the 
procedures specified in paragraph (l) of this AD.
    (ii) Option 2: Before further flight, do a splice repair of the 
rear spar upper and lower caps, in accordance with the 
Accomplishment Instructions of Boeing Alert Service Bulletin MD90-
57A026, Revision 1, dated February 23, 2011. Within 20,000 flight 
cycles after doing the splice repair, do an ETLF inspection and a UT 
inspection for any cracking in the repaired area of the rear spar 
lower cap, in accordance with the Accomplishment Instructions of 
Boeing Alert Service Bulletin MD90-57A026, Revision 1, dated 
February 23, 2011. Repeat the inspections thereafter at intervals 
not to exceed 3,000 flight cycles. If any cracking is found during 
any inspection required by this paragraph, before further flight, 
repair in accordance with a method approved in accordance with the 
procedures specified in paragraph (l) of this AD.

(i) Further Inspections if Cracking That Is Greater Than Two Inches Is 
Found or Is in the Rear Spar Lower Cap, Repair, and Repetitive Post-
Repair Inspections

    If, during any inspection required by paragraph (g) of this AD, 
any crack is found that is greater than two inches or is in the rear 
spar lower cap forward horizontal leg radius, before further flight, 
do an ETHF inspection for cracking on the affected wing rear spar 
upper cap at station Xrs = 164.000, in accordance with the 
Accomplishment Instructions of Boeing Alert Service Bulletin MD90-
57A026, Revision 1, dated February 23, 2011.
    (1) If no crack is found in the rear spar upper cap, before 
further flight, do a splice repair of the rear spar lower cap, in 
accordance with the Accomplishment Instructions of Boeing Alert 
Service Bulletin MD90-57A026, Revision 1, dated February 23, 2011. 
Within 20,000 flight cycles after doing the splice repair, do an 
ETLF inspection and a UT inspection for any cracking of the repaired 
area of the lower rear spar cap, in accordance with the 
Accomplishment Instructions of Boeing Alert Service Bulletin MD90-
57A026, Revision 1, dated February 23, 2011. Repeat the inspections 
thereafter at intervals not to exceed 3,000 flight cycles. If any 
cracking is found during any inspection required by this paragraph, 
before further flight, repair in accordance with a method approved 
in accordance with the procedures specified in paragraph (l) of this 
AD.
    (2) If any crack that is two inches or less is found in the rear 
spar upper cap, do the actions specified in paragraph (i)(2)(i) or 
(i)(2)(ii) of this AD.
    (i) Option 1: Do the actions specified in paragraphs 
(i)(2)(i)(A), (i)(2)(i)(B), and (i)(2)(i)(C) of this AD.
    (A) Before further flight, do a doubler repair of the rear spar 
upper cap and a splice repair of the rear spar lower cap, in 
accordance with the Accomplishment

[[Page 43181]]

Instructions of Boeing Alert Service Bulletin MD90-57A026, Revision 
1, dated February 23, 2011.
    (B) Within 13,500 flight cycles after doing the doubler repair 
required by paragraph (i)(2)(i)(A) of this AD, do an ETHF inspection 
for any cracking in the repaired area of the rear spar upper cap, in 
accordance with the Accomplishment Instructions of Boeing Alert 
Service Bulletin MD90-57A026, Revision 1, dated February 23, 2011. 
Repeat the inspection thereafter at intervals not to exceed 8,500 
flight cycles. If any cracking is found during any inspection 
required by this paragraph, before further flight, repair in 
accordance with a method approved in accordance with the procedures 
specified in paragraph (l) of this AD.
    (C) Within 20,000 flight cycles after doing the splice repair 
required by paragraph (i)(2)(i)(A) of this AD, do an ETLF inspection 
and a UT inspection for cracking in the repaired area of the rear 
spar lower cap, in accordance with the Accomplishment Instructions 
of Boeing Alert Service Bulletin MD90-57A026, Revision 1, dated 
February 23, 2011. Repeat the inspections thereafter at intervals 
not to exceed 3,000 flight cycles. If any cracking is found during 
any inspection required by this paragraph, before further flight, 
repair in accordance with a method approved in accordance with the 
procedures specified in paragraph (l) of this AD.
    (ii) Option 2: Before further flight, do a splice repair of the 
rear spar upper and lower caps, in accordance with the 
Accomplishment Instructions of Boeing Alert Service Bulletin MD90-
57A026, Revision 1, dated February 23, 2011. Within 20,000 flight 
cycles after doing the splice repair, do an ETLF inspection and a UT 
inspection for cracking in the repaired area of the rear spar lower 
cap, in accordance with the Accomplishment Instructions of Boeing 
Alert Service Bulletin MD90-57A026, Revision 1, dated February 23, 
2011. Repeat the inspections thereafter at intervals not to exceed 
3,000 flight cycles. If any cracking is found during any inspection 
required by this paragraph, before further flight, repair in 
accordance with a method approved in accordance with the procedures 
specified in paragraph (l) of this AD.
    (3) If any crack that is greater than two inches is found in the 
rear spar upper cap, before further flight, do a splice repair of 
the rear spar upper and lower caps, in accordance with the 
Accomplishment Instructions of Boeing Alert Service Bulletin MD90-
57A026, Revision 1, dated February 23, 2011. Within 20,000 flight 
cycles after doing the splice repair, do an ETLF inspection and a UT 
inspection for cracking in the repaired area of the rear spar lower 
cap, in accordance with the Accomplishment Instructions of Boeing 
Alert Service Bulletin MD90-57A026, Revision 1, dated February 23, 
2011. Repeat the inspections thereafter at intervals not to exceed 
3,000 flight cycles. If any cracking is found during any inspection 
required by this paragraph, before further flight, repair in 
accordance with a method approved in accordance with the procedures 
specified in paragraph (l) of this AD.

(j) Repeat ETHF Inspection

    For airplanes on which any splice repair was required by this 
AD: Within 30,000 flight cycles after the splice repair, repeat the 
inspection required by paragraph (g) of this AD for the repaired 
wing. If no cracking is found on the on the rear spar lower cap of 
the repaired wing, repeat the inspection on the affected wing rear 
spar lower cap thereafter at intervals not to exceed 2,550 flight 
cycles. If any cracking is found during any inspection required by 
this paragraph, before further flight, repair in accordance with a 
method approved in accordance with the procedures specified in 
paragraph (l) of this AD.

(k) Credit for Previous Actions

    This paragraph provides credit for the actions required by 
paragraphs (g), (h), and (i) of this AD, if those actions were 
performed before the effective date of this AD using Boeing Alert 
Service Bulletin MD90-57A026, dated February 11, 2010.

(l) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, Los Angeles Aircraft Certification Office 
(ACO), FAA, has the authority to approve AMOCs for this AD, if 
requested using the procedures found in 14 CFR 39.19. In accordance 
with 14 CFR 39.19, send your request to your principal inspector or 
local Flight Standards District Office, as appropriate. If sending 
information directly to the manager of the ACO, send it to the 
attention of the person identified in the Related Information 
section of this AD.
    (2) Before using any approved AMOC, notify your appropriate 
principal inspector, or lacking a principal inspector, the manager 
of the local flight standards district office/certificate holding 
district office.
    (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 the 
Boeing Commercial Airplanes Organization Designation Authorization 
(ODA) that 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.

(m) Related Information

    (1) For more information about this AD, contact Roger Durbin, 
Airframe Branch, ANM-120L, FAA, Los Angeles ACO, 3960 Paramount 
Boulevard, Lakewood, California 90712-4137; phone: (562) 627-5233; 
fax: (562) 627-5210; email: roger.durbin@faa.gov.
    (2) For service information identified in this AD, contact 
Boeing Commercial Airplanes, Attention: Data & Services Management, 
3855 Lakewood Boulevard, MC D800-0019, Long Beach, California 90846-
0001; telephone 206-544-5000, extension 2; fax 206-766-5683; 
Internet https://www.myboeingfleet.com. You may review copies of the 
referenced service information at the FAA, Transport Airplane 
Directorate, 1601 Lind Avenue SW., Renton, Washington. For 
information on the availability of this material at the FAA, call 
425-227-1221.

    Issued in Renton, Washington, on July 13, 2012.
Michael Kaszycki,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2012-17968 Filed 7-23-12; 8:45 am]
BILLING CODE 4910-13-P