- Effective
- December 5, 2012
- Published
- October 31, 2012 · 77 FR 65803–65805
- Issued
- October 12, 2012
- Model
- MD-90-30
- Data sheet
- TCDSA6WE
- Registered aircraft
- 5 matched by model
- Product
- Aircraft · Large airplane
- ATA chapter
- 57 · Wings
- Amendment
- 39-17234
- Docket
- FAA-2012-0728
- Project
- 2012-NM-050-AD
- Issued as
- Final rule
Unofficial copy from the Federal Register XML, document 2012-26187. Only the govinfo PDF is the legal edition. DRS record last changed May 30, 2024.
Copies of the files this page was built from, with their SHA-256. Retrieved October 18, 2026.
| File | Size | SHA-256 | Original |
|---|---|---|---|
| Official PDF | 234 KB | d9263024…9ad21e0 | 2012-26187.pdf on govinfo.gov |
| Federal Register XML | 19 KB | 27fe0d2a…a2b5292 | 2012-26187.xml on federalregister.gov |
| FAA DRS HTML attachment | 57 KB | 4dc5fc91…fa48efd | FAA DRS (API key needed) |
| FAA DRS PDF | 37 KB | 81f930da…4e791b8 | FAA DRS (API key needed) |
On this page
Summary
We are adopting a new airworthiness directive (AD) for certain The Boeing Company Model MD-90-30 airplanes. This AD was prompted by reports of fatigue cracks found in Stringer 11 at the outboard flap, inboard drive hinge at Station Xrs=164.000. This AD requires repetitive inspections for cracks in Stringer 11, and a splice repair if necessary; and repetitive post-repair inspections, and repair if necessary. We are issuing this AD to detect and correct such cracking, which could result in the wing structure not supporting the limit load condition, which could lead to loss of the structural integrity of the wing.
The airworthiness directive
2012-21-18 The Boeing Company: Amendment 39-17234; Docket No. FAA-2012-0728; Directorate Identifier 2012-NM-050-AD.
(a) Effective Date
PDF page 2This AD is effective December 5, 2012.
(b) Affected ADs
PDF page 2None.
(c) Applicability
PDF page 2This AD applies to The Boeing Company Model MD-90-30 airplanes, certificated in any category, as identified in Boeing Alert Service Bulletin MD90-57A030, dated February 14, 2012.
(d) Subject
PDF page 2Joint Aircraft System Component (JASC)/Air Transport Association (ATA) of America Code 57, Wings.
(e) Unsafe Condition
PDF page 2This AD was prompted by reports of fatigue cracks found in Stringer 11 at the outboard flap, inboard drive hinge at Station Xrs=164.000. We are issuing this AD to detect and correct such cracking, which could result in the wing structure not supporting the limit load condition, which could lead to loss of the structural integrity of the wing.
(f) Compliance
PDF page 2Comply with this AD within the compliance times specified, unless already done.
(g) Repetitive Inspections
PDF page 2Before the accumulation of 14,000 total flight cycles, or within 9,470 flight cycles after the effective date of this AD: Whichever occurs later, do an in-tank eddy current high frequency (ETHF) inspection for cracks in Stringer 11 at the outboard flap, inboard drive hinge at Station Xrs=164.000 of the left and right wings, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin MD90-57A030, dated February 14, 2012. If no cracking is found, repeat the inspection thereafter at intervals not to exceed 31,000 flight cycles.
(h) Splice Repair
PDF page 2If any cracking is found during any inspection required by paragraph (g) of this AD: Before further flight, do a splice repair, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin MD90-57A030, dated February 14, 2012.
(i) Post-Repair Inspection
PDF page 2Within 42,000 flight cycles after doing the splice repair specified in paragraph (h) of this AD: Do an ETHF inspection for cracks in Stringer 11 at the outboard flap, inboard drive hinge at Station Xrs=164.000, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin MD90-57A030, dated February 14, 2012. Repeat the inspection thereafter at intervals not to exceed 31,000 flight cycles. If any crack is found: Before further flight, repair the crack using a method approved in accordance with the procedures specified in paragraph (j) of this AD.
(j) Alternative Methods of Compliance (AMOCs)
PDF page 3(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 54, and the approval must specifically refer to this AD.
(k) Related Information
PDF page 3For more information about this AD, 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.
(l) Material Incorporated by Reference
PDF page 3(1) The Director of the Federal Register approved the incorporation by reference (IBR) of the service information listed in this paragraph under 5 U.S.C. 552(a) and 1 CFR part 51.
(2) You must use this service information as applicable to do the actions required by this AD, unless the AD specifies otherwise.
(i) Boeing Alert Service Bulletin MD90-57A030, dated February 14, 2012.
(ii) Reserved.
(3) For The Boeing Company Airplanes service information identified in this AD, contact Boeing Commercial Airplanes, Attention: Data & Services Management, 3855 Lakewood Boulevard, MC D800-0019, Long Beach, CA 90846-0001; telephone 206-544-5000, extension 2; fax 206-766-5683; Internet https://www.myboeingfleet.com.
(4) You may view this service information at 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.
(5) You may view this service information that is incorporated by reference at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, call 202-741-6030, or go to: http://www.archives.gov/federal-register/cfr/ibr-locations.html.
Rule preamble
The FAA’s background, reasoning and cost estimate, published with the AD.
DatesPage 1
This AD is effective December 5, 2012.
The Director of the Federal Register approved the incorporation by reference of a certain publication listed in the AD as of December 5, 2012.
AddressesPage 1
For service information identified in this AD, contact Boeing Commercial Airplanes, Attention: Data & Services Management, 3855 Lakewood Boulevard, MC D800-0019, Long Beach, CA 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.
For further information contactPage 1
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.
DiscussionPage 1
We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 to include an AD that would apply to the specified products. That NPRM published in the Federal Register on August 1, 2012 (77 FR 45515). That NPRM proposed to require repetitive inspections for cracks in Stringer 11, and a splice repair if necessary; and repetitive post-repair inspections, and repair if necessary.
CommentsPage 1
We gave the public the opportunity to participate in developing this AD. We have considered the comment received. Boeing supports the NPRM (77 FR 45515, August 1, 2012).
ConclusionPage 1
We reviewed the relevant data, considered the comment received, and determined that air safety and the public interest require adopting the AD as proposed—except for minor editorial changes. We have determined that these minor changes:
• Are consistent with the intent that was proposed in the NPRM (77 FR 45515, August 1, 2012) for correcting the unsafe condition; and
• Do not add any additional burden upon the public than was already proposed in the NPRM (77 FR 45515, August 1, 2012).
Costs of CompliancePage 1
We estimate that this AD affects 52 airplanes of U.S. registry.
We estimate the following costs to comply with this AD:
| Action | Labor cost | Parts cost | Cost per product | Cost on U.S. operators |
|---|---|---|---|---|
| Inspection | 13 work-hours × $85 per hour = $1,105 per inspection cycle | None | $1,105 per inspection cycle | $57,460 per inspection cycle |
| Post-repair inspection | 13 work-hours × $85 per hour = $1,105 | None | $1,105 | $57,460. |
We estimate the following costs to do any necessary repairs that would be required based on the results of the inspection. We have no way of determining the number of aircraft that might need these repairs:
| Action | Labor cost | Parts cost | Cost per product |
|---|---|---|---|
| Splice repair per wing | 93 work-hours × $85 per hour = $7,905 | $28,126 | $36,031 |
We have received no definitive data that would enable us to provide cost estimates for the on-condition actions of the post-repair inspection specified in this AD.
Authority for This RulemakingPage 2
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 findingsPage 2
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.
For the reasons discussed above, I certify that this AD:
(1) Is not a “significant regulatory action” under Executive Order 12866,
(2) Is not a “significant rule” under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979),
(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.
Adoption of the AmendmentPage 2
Accordingly, under the authority delegated to me by the Administrator, the FAA amends 14 CFR part 39 as follows:
Adoption of the amendmentPage 2
1. The authority citation for part 39 continues to read as follows:
2. The FAA amends § 39.13 by adding the following new airworthiness directive (AD):
Affected TCDS · 1
The type certificate data sheets for the models this AD names, matched by model and maker.
Registered aircraft · 5
Registered aircraft whose airframe or engine model this AD names. Matched by model only, so check each against the AD’s applicability.
| 1995 | 1 |
|---|---|
| 1996 | 2 |
| 1998 | 1 |
| 1999 | 1 |