Source: https://www.federalregister.gov/documents/2017/02/10/2017-01824/airworthiness-directives-the-boeing-company-airplanes
Timestamp: 2018-03-24 11:04:04
Document Index: 445358292

Matched Legal Cases: ['art 39', 'art 4', 'art 5', '§\u200939', 'arts 1', 'art 2', 'art 4', 'art 3', 'art 5', 'art 4', 'art 5', 'art 51']

82 FR 10258
Docket No. FAA-2016-6670
Directorate Identifier 2016-NM-006-AD
Amendment 39-18789
AD 2017-02-10
FAA-2016-6670
2015-NM-006-AD The Boeing Company Model 737?600, ?700, ?700C, ?800, and ?900 series airplanes
U.S. DOT/FAA - SB-737-53-1294-02
Request To Clarify Access and Restoration Requirements
Clarification of Exception to Repetitive Intervals
(h) Skin Repair or Optional Preventive Modification
(j) Supplemental Inspections Not Required by This AD
https://www.federalregister.gov/d/2017-01824 https://www.federalregister.gov/d/2017-01824
We are superseding Airworthiness Directive (AD) 2013-19-04 for certain The Boeing Company Model 737-600, -700, -700C, -800, and -900 series airplanes. AD 2013-19-04 required repetitive inspections for cracking of the skin around the fasteners common to the ends of certain bulkhead chords, and related investigative actions and corrective actions if necessary; and Start Printed Page 10259provided an optional terminating modification. This new AD reduces the inspection threshold and repetitive inspection intervals. This AD was prompted by a report of cracks found in the skin at fasteners of certain bulkhead chords. We are issuing this AD to address the unsafe condition on these products.
For service information identified in this final rule, contact Boeing Commercial Airplanes, Attention: Contractual & Data Services (C&DS), 2600 Westminster Blvd., MC 110-SK57, Seal Beach, CA 90740-5600; telephone 562-797-1717; Internet https://www.myboeingfleet.com. You may view this referenced service information at the FAA, Transport Airplane Directorate, 1601 Lind Avenue SW., Renton, WA. For information on the availability of this material at the FAA, call 425-227-1221. It is also available on the Internet at http://www.regulations.gov by searching for and locating Docket No. FAA-2016-6670.
You may examine the AD docket on the Internet at http://www.regulations.gov by searching for and locating Docket No. FAA-2016-6670; 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 AD, the regulatory evaluation, any comments received, and other information. The address for the Docket Office (phone: 800-647-5527) is Docket Management Facility, U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue SE., Washington, DC 20590.
We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 to supersede AD 2013-19-04, Amendment 39-17586 (78 FR 59801, September 30, 2013) (“AD 2013-19-04”). AD 2013-19-04 applied to certain The Boeing Company Model 737-600, -700, -700C, -800, and -900 series airplanes. The NPRM published in the Federal Register on May 12, 2016 (81 FR 29505) (“the NPRM”). The NPRM was prompted by a report of cracks found in the skin at body station (STA) 540 just below stringer S-22L. The NPRM proposed to continue to require repetitive detailed and high frequency eddy current inspections for cracking of the skin around the eight fasteners common to the ends of the STA 540 bulkhead chords between stringers S-22 and S-23, left and right sides; related investigative actions and corrective actions, if necessary; and to provide an optional terminating modification. The NPRM also proposed to reduce the inspection threshold and repetitive inspection intervals. We are issuing this AD to detect and correct fatigue cracking in the fuselage skin around the eight fasteners securing the STA 540 bulkhead chords, which could result in rapid decompression of the cabin.
Boeing and United Airlines had no objections to the NPRM.
Aviation Partners Boeing stated that installation of winglets, as provided in Supplemental Type Certificate (STC) ST00830SE, does not affect the ability to accomplish the actions proposed in the NPRM.
We concur with the commenter. We have redesignated paragraph (c) of the proposed AD as (c)(1) and added paragraph (c)(2) to this AD to state that installation of STC ST00830SE does not affect the ability to accomplish the actions required by this AD. Therefore, for airplanes on which STC ST00830SE is installed, a “change in product” alternative method of compliance (AMOC) approval request is not necessary to comply with the requirements of 14 CFR 39.17.
All Nippon Airways requested that we clarify if the access and restoration instructions specified in the service information referenced in paragraph (k) of the proposed AD are required actions.
We agree to clarify this issue. Access and restoration actions are not part of the actions required to correct the unsafe condition identified in this AD. Therefore, access and restoration actions were excluded from the required actions in AD 2013-19-04 and are excluded from the required actions in this AD. We have added the service information referenced in paragraph (k) of this AD to paragraph (i)(4) of this AD. Paragraph (i)(4) of this AD specifies that the access and restoration actions specified in the referenced service information are not required by this AD.
Southwest Airlines (SWA) requested that we clarify the corrective action for drilling the new drag link assembly. SWA stated that the service information only provides instructions for parts constructed of aluminum and that the drag link assembly is made from titanium.
We agree that clarification is necessary. Boeing has informed us that revised service information is forthcoming. However, since the revised service information is not yet available, we do not consider that delaying this action until after the release of the manufacturer's revised service bulletin is warranted. When this service information becomes available, and upon satisfactory review, we plan to approve it as a global alternative method of compliance (AMOC) to the appropriate requirements of this AD. The issue raised by SWA affects only the on-condition repair instructions and not the required inspection to detect the identified unsafe condition. We have added paragraph (i)(5) to this AD to specify that repairs provided in Part 4 or Part 5 of the Accomplishment Instructions of Boeing Special Attention Service Bulletin 737-53-1294, Revision 2, dated December 9, 2015 (“SASB 737-53-1294 R2”), must be done before further flight, using a method approved in accordance with the procedures specified in paragraph (l) of this AD. We have revised paragraphs (g) and (h) of this AD accordingly.
For clarity, we have changed the format of paragraph (g) of this AD to make it clear the exceptions apply to the entire paragraph, including the repetitive inspection sentence specified in paragraph (g) of this AD.
We have clarified paragraph (h) of this AD to specify that accomplishing the skin repair or preventive modification, Start Printed Page 10260as specified in the applicable part of the Accomplishment Instructions of Boeing SASB 737-53-1294 R2, is terminating action for the side on which the skin repair or preventive modification is done.
We reviewed SASB 737-53-1294 R2. The service information describes procedures for inspecting the skin around the eight fasteners common to the ends of the STA 540 bulkhead chords between stringers S-22 and S-23, left and right sides, for cracking, repairing cracks, and installing a chord splice as a preventive modification. This service information is reasonably available because the interested parties have access to it through their normal course of business or by the means identified in the ADDRESSES section.
We estimate that this AD affects 903 airplanes of U.S. registry.
Inspection (left and right sides) 12 work-hours × $85 per hour = $1,020 per inspection cycle $0 $1,020 per inspection cycle $921,060 per inspection cycle.
We estimate the following costs to do any necessary repairs and inspections that will be required based on the results of the inspection. We have no way of determining the number of aircraft that might need these repairs:
Skin repair (each side) 39 work-hours × $85 per hour = $3,315 Up to $5,635 Up to $8,950.
2. The FAA amends § 39.13 by removing Airworthiness Directive (AD) 2013-19-04, Amendment 39-17586 ( 78 FR 59801, September 30, 2013), and adding the following new AD:
2017-02-10 The Boeing Company: Amendment 39-18789; Docket No. FAA-2016-6670; Directorate Identifier 2016-NM-006-AD.
This AD replaces AD 2013-19-04, Amendment 39-17586 (78 FR 59801, September 30, 2013) (“AD 2013-19-04”).Start Printed Page 10261
(1) This AD applies to The Boeing Company Model 737-600, -700, -700C, -800, and -900 series airplanes, certificated in any category, as identified in Boeing Special Attention Service Bulletin 737-53-1294, Revision 2, dated December 9, 2015 (“SASB 737-53-1294 R2”).
(2) Installation of Supplemental Type Certificate (STC) ST00830SE [http://rgl.faa.gov/​Regulatory_​and_​Guidance_​Library/​rgstc.nsf/​0/​184DE9A71EC3FA5586257EAE00707DA6?​OpenDocument&​Highlight=​st00830se] does not affect the ability to accomplish the actions required by this AD. Therefore, for airplanes on which STC ST00830SE is installed, a “change in product” alternative method of compliance (AMOC) approval request is not necessary to comply with the requirements of 14 CFR 39.17.
This AD was prompted by a report of cracks found in the skin at body station (STA) 540 just below the left side of stringer S-22. We are issuing this AD to detect and correct fatigue cracking in the fuselage skin around the eight fasteners securing the STA 540 bulkhead chords, which could result in rapid decompression of the cabin.
Except as required by paragraphs (i)(1) and (i)(2) of this AD: At the applicable time specified in table 1 of paragraph 1.E., “Compliance,” of SASB 737-53-1294 R2, do detailed and high frequency eddy current (HFEC) inspections for cracking of the skin in the area around the eight fasteners securing the STA 540 bulkhead chords between stringers S-22 and S-23; and do all applicable related investigative and corrective actions; in accordance with Parts 1, 2, 3, 4, and 5 of the Accomplishment Instructions of SASB 737-53-1294 R2, except as required by paragraphs (i)(3), (i)(4), and (i)(5) of this AD. Do all applicable related investigative and corrective actions before further flight. Except as required by paragraph (i)(2) of this AD, repeat the detailed and HFEC inspections thereafter at the intervals specified in table 1 of paragraph 1.E., “Compliance,” of SASB 737-53-1294 R2, until the optional preventive modification specified in paragraph (h) of this AD is done.
Accomplishing the skin repair or preventive modification, including an HFEC inspection for cracking of the skin and STA 540 bulkhead chords, and all applicable repairs, in accordance with paragraph 3.B, Part 2 or Part 4 (left side), or Part 3 or Part 5 (right side), as applicable, of the Accomplishment Instructions of SASB 737-53-1294 R2, except as required by paragraphs (i)(2) and (i)(5) of this AD, terminates the inspection requirements of paragraph (g) of this AD for the side on which the skin repair or preventive modification is done.
(1) Where paragraph 1.E., “Compliance,” of SASB 737-53-1294 R2, specifies a compliance time “after the Revision 2 date of this service bulletin,” this AD requires compliance within the specified compliance time after the effective date of this AD.
(2) For airplanes on which Boeing Business Jet Lower Cabin Altitude Supplemental Type Certificate (STC) ST01697SE (http://rgl.faa.gov/​Regulatory_​and_​Guidance_​Library/​rgstc.nsf/​0/​0812969a86af879b8625766400600105/​$FILE/​ST01697SE.pdf) (6,500 feet maximum cabin altitude in lieu of 8,000 feet) has been incorporated, the flight-cycle related compliance times for the inspection required by paragraph (g) of this AD are different from those specified in paragraph 1.E., “Compliance,” of SASB 737-53-1294 R2. All initial compliance times specified in total flight cycles or flight cycles must be reduced to half of those specified in SASB 737-53-1294 R2. All repetitive interval compliance times specified in flight cycles must be reduced to one-quarter of those specified in paragraph 1.E., “Compliance,” of SASB 737-53-1294 R2.
(3) If any cracking is found during any inspection required by this AD, and SASB 737-53-1294 R2, specifies to contact Boeing for appropriate action: Before further flight, repair using a method approved in accordance with the procedures specified in paragraph (l) of this AD.
(4) The access and restoration actions identified in the Accomplishment Instructions of Boeing Special Attention Service Bulletin 737-53-1294, dated March 31, 2011; Boeing Special Attention Service Bulletin 737-53-1294, Revision 1, dated June 14, 2013; or SASB 737-53-1294 R2; are not required by this AD. Operators may perform those actions in accordance with accepted maintenance procedures.
(5) For doing repairs specified in Part 4 or Part 5 of the Accomplishment Instructions of SASB 737-53-1294 R2: Before further flight, repair using a method approved in accordance with the procedures specified in paragraph (l) of this AD.
Table 2 of paragraph 1.E., “Compliance,” of SASB 737-53-1294 R2, specifies post-modification airworthiness limitation inspections in compliance with 14 CFR 25.571(a)(3) at the modified locations, which support compliance with 14 CFR 121.1109(c)(2) or 129.109(b)(2). As airworthiness limitations, these inspections are required by maintenance and operational rules. It is therefore unnecessary to mandate them in this AD. Deviations from these inspections require FAA approval, but do not require an AMOC.
This paragraph provides credit for the actions required by paragraphs (g) and (h) of this AD, if those actions were performed before the effective date of this AD using Boeing Special Attention Service Bulletin 737-53-1294, dated March 31, 2011, which is not incorporated by reference in this AD; or Boeing Special Attention Service Bulletin 737-53-1294, Revision 1, dated June 14, 2013, which was incorporated by reference in AD 2013-19-04.
(4) AMOCs approved previously for the optional preventive modification installed in accordance with paragraph (h) of AD 2013-19-04, and AMOCs approved previously for repairs for AD 2013-19-04, are approved as AMOCs for the corresponding provisions of this AD, provided that such modification or repair included installation of the splice plate as specified in Boeing Special Attention Service Bulletin 737-53-1294, except as provided by paragraph (l)(5) of this AD.
(5) The time-limited repair approved as specified in FAA Letter 120S-15-140, dated June 3, 2015, is approved as an AMOC to the corresponding requirements of this AD.
(1) The Director of the Federal Register approved the incorporation by reference Start Printed Page 10262(IBR) of the service information listed in this paragraph under 5 U.S.C. 552(a) and 1 CFR part 51.
(i) Boeing Special Attention Service Bulletin 737-53-1294, Revision 2, dated December 9, 2015.
[FR Doc. 2017-01824 Filed 2-9-17; 8:45 am]