AD 2012-21-18
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | The Boeing Company | MD-90-30 | Airworthiness Directives; The Boeing Company Airplanes |
Unsafe Condition
Fatigue cracks found in Stringer 11 at the outboard flap, inboard drive hinge at Station Xrs=164.000, which could result in the wing structure not supporting the limit load condition, leading to loss of the structural integrity of the wing.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Conduct repetitive inspections for cracks in Stringer 11 using in-tank eddy current high frequency (ETHF) inspections. Perform a splice repair if cracks are found, followed by post-repair inspections at specified intervals. Repair any cracks found during post-repair inspections.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Within 9,470 flight cycles after the effective date of this AD or before the accumulation of 14,000 total flight cycles, whichever occurs later.
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
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.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
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.
Applicability Source Text
Show captured applicability text from the source AD
(c) Applicability
This 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.
Document Text
Show stored source text (verify against official source)
[Federal Register Volume 77, Number 211 (Wednesday, October 31, 2012)]
[Rules and Regulations]
[Pages 65803-65805]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2012-26187]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2012-0728; Directorate Identifier 2012-NM-050-AD;
Amendment 39-17234; AD 2012-21-18]
RIN 2120-AA64
Airworthiness Directives; The Boeing Company Airplanes
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final rule.
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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.
DATES: 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.
ADDRESSES: 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 <a href="https://www.myboeingfleet.com">https://www.myboeingfleet.com</a>. 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 <a href="http://www.regulations.gov">http://www.regulations.gov</a>; 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 Document 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.
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: <a href="/cdn-cgi/l/email-protection#8dffe2eae8ffa3e9f8ffefe4e3cdebececa3eae2fb"><span class="__cf_email__" data-cfemail="03716c6466712d677671616a6d436562622d646c75">[email protected]</span></a>.
SUPPLEMENTARY INFORMATION:
Discussion
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.
Comments
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).
Conclusion
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:
<bullet> Are consistent with the intent that was proposed in the
NPRM (77 FR 45515, August 1, 2012) for correcting the unsafe condition;
and
<bullet> Do not add any additional burden upon the public than was
already proposed in the NPRM (77 FR 45515, August 1, 2012).
Costs of Compliance
We estimate that this AD affects 52 airplanes of U.S. registry.
We estimate the following costs to comply with this AD:
[[Page 65804]]
Estimated Costs
----------------------------------------------------------------------------------------------------------------
Cost on U.S.
Action Labor cost Parts cost Cost per product operators
----------------------------------------------------------------------------------------------------------------
Inspection..................... 13 work-hours x None............... $1,105 per $57,460 per
$85 per hour = inspection cycle. inspection cycle
$1,105 per
inspection cycle.
Post-repair inspection......... 13 work-hours x None............... $1,105............ $57,460.
$85 per hour =
$1,105.
----------------------------------------------------------------------------------------------------------------
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:
On-Condition Costs
----------------------------------------------------------------------------------------------------------------
Action Labor cost Parts cost Cost per product
----------------------------------------------------------------------------------------------------------------
Splice repair per wing..................... 93 work-hours x $85 per hour $28,126 $36,031
= $7,905.
----------------------------------------------------------------------------------------------------------------
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 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
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.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by
reference, Safety.
Adoption of the Amendment
Accordingly, under the authority delegated to me by the
Administrator, the FAA amends 14 CFR part 39 as follows:
PART 39--AIRWORTHINESS DIRECTIVES
0
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]
0
2. The FAA amends Sec. 39.13 by adding the following new airworthiness
directive (AD):
2012-21-18 The Boeing Company: Amendment 39-17234; Docket No. FAA-
2012-0728; Directorate Identifier 2012-NM-050-AD.
(a) Effective Date
This AD is effective December 5, 2012.
(b) Affected ADs
None.
(c) Applicability
This 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
Joint Aircraft System Component (JASC)/Air Transport Association
(ATA) of America Code 57, Wings.
(e) Unsafe Condition
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. 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
Comply with this AD within the compliance times specified,
unless already done.
(g) Repetitive Inspections
Before 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
If 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
Within 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
[[Page 65805]]
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)
(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
For 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:
<a href="/cdn-cgi/l/email-protection#b0c2dfd7d5c29ed4c5c2d2d9def0d6d1d19ed7dfc6"><span class="__cf_email__" data-cfemail="c3b1aca4a6b1eda7b6b1a1aaad83a5a2a2eda4acb5">[email protected]</span></a>.
(l) Material Incorporated by Reference
(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 <a href="https://www.myboeingfleet.com">https://www.myboeingfleet.com</a>.
(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: <a href="http://www.archives.gov/federal-register/cfr/ibr-locations.html">http://www.archives.gov/federal-register/cfr/ibr-locations.html</a>.
Issued in Renton, Washington, on October 12, 2012.
Kalene C. Yanamura,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 2012-26187 Filed 10-30-12; 8:45 am]
BILLING CODE 4910-13-P
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