[Federal Register Volume 77, Number 148 (Wednesday, August 1, 2012)]
[Proposed Rules]
[Pages 45515-45517]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2012-18616]
-----------------------------------------------------------------------
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2012-0728; Directorate Identifier 2012-NM-050-AD]
RIN 2120-AA64
Airworthiness Directives; The Boeing Company Airplanes
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Notice of proposed rulemaking (NPRM).
-----------------------------------------------------------------------
SUMMARY: We propose to adopt a new airworthiness directive (AD) for
certain The Boeing Company Model MD-90-30 airplanes. This proposed 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
proposed AD would require repetitive inspections for cracks in Stringer
11, and a splice repair if necessary; and repetitive post-repair
inspections, and repair if necessary. We are proposing 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: We must receive comments on this proposed AD by September 17,
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,
[[Page 45516]]
M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue
SE., Washington, DC 20590.
Hand Delivery: Deliver to Mail address above between 9
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
For service information identified in this proposed 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: [email protected].
SUPPLEMENTARY INFORMATION:
Comments Invited
We invite you to send any written relevant data, views, or
arguments about this proposal. Send your comments to an address listed
under the ADDRESSES section. Include ``Docket No. FAA-2012-0728;
Directorate Identifier 2012-NM-050-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 received reports of fatigue cracks found in Stringer 11 at the
outboard flap, inboard drive hinge at Station Xrs=164.000 on Model MD-
80 airplanes. Model MD-90 airplanes share the same structure design as
the MD-80, and are also susceptible to cracking. The cracking occurred
at the end fastener of the wing bulkhead clip attachment to the
stringer. If undetected, a crack in the stringer may grow until the
stringer severs, initiating a crack in the wing lower skin. This
condition, if not corrected, could result in the wing structure not
supporting the limit load condition, which could lead to loss of the
structural integrity of the wing.
Relevant Service Information
We reviewed Boeing Alert Service Bulletin MD90-57A030, dated
February 14, 2012. The service information describes procedures for
repetitive in-tank eddy current high frequency (ETHF) inspections for
cracks in Stringer 11 at the outboard flap, inboard drive hinge at
Station Xrs=164.000 on the left and right wings, and a splice repair if
necessary; and repetitive post-repair inspections, and repair if
necessary.
FAA's Determination
We are proposing this AD because we evaluated all the relevant
information and determined the unsafe condition described previously is
likely to exist or develop in other products of this same type design.
Proposed AD Requirements
This proposed AD would require accomplishing the actions specified
in the service information described previously, except as discussed
under ``Differences Between the Proposed AD and the Service
Information.
Differences Between the Proposed AD and the Service Information
The service bulletin specifies to contact the manufacturer for
instructions on how to repair certain conditions, 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 52 airplanes of U.S.
registry.
We estimate the following costs to comply with this proposed AD:
Estimated Costs
----------------------------------------------------------------------------------------------------------------
Cost on U.S.
Action Labor cost Parts cost Cost per product operators
----------------------------------------------------------------------------------------------------------------
Inspection....................... 13 work-hours x $85 None......... $1,105 per $57,460 per
per hour = $1,105 inspection cycle. inspection cycle.
per inspection
cycle.
Post-repair inspection........... 13 work-hours x $85 None......... $1,105............. $57,460.
per hour = $1,105.
----------------------------------------------------------------------------------------------------------------
We estimate the following costs to do any necessary repairs that
would be required based on the results of the proposed inspection. We
have no way of determining the number of aircraft that might need these
repairs:
On-Condition Costs
----------------------------------------------------------------------------------------------------------------
Cost per
Action Labor cost Parts cost product
----------------------------------------------------------------------------------------------------------------
Splice repair per wing..................... 93 work-hours x $85 per hour = $28,126 $36,031
$7,905.
----------------------------------------------------------------------------------------------------------------
[[Page 45517]]
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 proposed 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-2012-0728; Directorate Identifier
2012-NM-050-AD.
(a) Comments Due Date
We must receive comments by September 17, 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 the 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 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
(1) 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:
[email protected].
(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 23, 2012.
Kalene C. Yanamura,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 2012-18616 Filed 7-31-12; 8:45 am]
BILLING CODE 4910-13-P