[Federal Register Volume 75, Number 76 (Wednesday, April 21, 2010)]
[Proposed Rules]
[Pages 20792-20794]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2010-9112]
-----------------------------------------------------------------------
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2010-0383; Directorate Identifier 2009-NM-214-AD]
RIN 2120-AA64
Airworthiness Directives; The Boeing Company Model 747-100, 747-
100B, 747-100B SUD, 747-200B, 747-200C, 747-200F, 747-300, 747-400,
747SR, and 747SP Series 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 Model 747-100, 747-100B, 747-100B SUD, 747-200B, 747-200C, 747-
200F, 747-300, 747-400, 747SR, and 747SP series airplanes. This
proposed AD would require repetitive detailed inspections of certain
overwing intercostal webs, and related investigative and corrective
actions if necessary. This proposed AD results from reports of cracks
in overwing intercostal webs. We are proposing this AD to detect and
correct such cracking, which could grow and result in a severed
intercostal. If an intercostal is severed, cracks could develop in the
adjacent frame structure and skin, resulting in a rapid loss of cabin
pressure.
DATES: We must receive comments on this proposed AD by June 7, 2010.
ADDRESSES: You may send comments 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 proposed AD, contact
Boeing Commercial Airplanes, Attention: Data & Services Management,
P.O. Box 3707, MC 2H-65, Seattle, Washington 98124-2207; telephone 206-
544-5000, extension 1; fax 206-766-5680; e-mail [email protected];
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 (telephone 800-647-5527) is in the
ADDRESSES section. Comments will be available in the AD docket shortly
after receipt.
[[Page 20793]]
FOR FURTHER INFORMATION CONTACT: Ivan Li, Aerospace Engineer, Airframe
Branch, ANM-120S, FAA, Seattle Aircraft Certification Office (ACO),
1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone (425)
917-6437; fax (425) 917-6590.
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-2010-0383;
Directorate Identifier 2009-NM-214-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 have received several reports of cracks in overwing intercostal
webs between station (STA) 1160 and STA 1220. Most of the cracks were
found near the intercostal lower chord and a few cracks were found near
the intercostal upper chord. The cracks ranged from 0.2 inch to 3.5
inches long. The cracks are caused by cyclic buckling of the web from
normal flight loads. The earliest report of a web crack occurred on an
airplane with 3,697 flight cycles; however, no cracks have been
reported in the upper or lower chord of the overwing intercostals. This
condition, if not corrected, could result in crack growth and a severed
intercostal. If an intercostal is severed, cracks could develop in the
adjacent frame structure and skin, resulting in rapid loss of cabin
pressure.
Relevant Service Information
We have reviewed Boeing Alert Service Bulletin 747-53A2750, dated
August 27, 2009. Boeing Alert Service Bulletin 747-53A2750, dated
August 27, 2009, describes procedures for doing a repetitive detailed
inspection for cracking of the left-side and right-side overwing
intercostal webs at STAs 1160, 1180, 1200, and 1220, and related
investigative and corrective actions if necessary. The related
investigative action is doing a detailed inspection for cracking of the
upper chord, lower chord, and stiffener of the intercostal and adjacent
frame assembly structure if a crack is found in the web of an overwing
intercostal. Depending on findings, the corrective actions are
replacing any cracked overwing intercostal web (the replacement of the
overwing intercostal web includes doing an open-hole HFEC inspection
for cracking of the fastener holes common to the replacement); and
contacting Boeing for repair instructions of any cracked intercostal
upper chord, lower chord, stiffener, or adjacent frame assembly
structure, and of any crack found during any open-hole HFEC
inspections, and doing the repair.
For any airplane having a STA 1160, 1180, 1200, or 1220 overwing
intercostal web that has been replaced in accordance with this service
bulletin, Boeing Alert Service Bulletin 747-53A2750, dated August 27,
2009, specifies procedures for doing repetitive detailed inspections
for cracking of the replaced web, and related investigative and
corrective actions if necessary. Related investigative actions include
doing a detailed inspection for cracking of the upper chord, lower
chord, and stiffener of the intercostal, and adjacent frame assembly
structure. Corrective actions include replacing any cracked overwing
intercostal web; and contacting Boeing for repair instructions of any
cracked intercostal upper chord, lower chord, stiffener, or adjacent
frame assembly structure, and of any crack found during any open-hole
HFEC inspections, and doing the repair.
FAA's Determination and Requirements of This Proposed AD
We are proposing this AD because we evaluated all relevant
information and determined the unsafe condition described previously is
likely to exist or develop in other products of the same type design.
This proposed AD would require accomplishing the actions specified in
the service information described previously, except as discussed under
``Differences Between the Proposed Rule and Service Bulletin.''
Differences Between the Proposed Rule and Service Bulletin
Boeing Alert Service Bulletin 747-53A2750, dated August 27, 2009,
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:
Using 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 would affect 86 airplanes of U.S.
registry. The following table provides the estimated costs for U.S.
operators to comply with this proposed AD.
Table--Estimated costs
--------------------------------------------------------------------------------------------------------------------------------------------------------
Number of U.S.-
Action Work hours Average labor Parts Cost per product registered Fleet cost
rate per hour airplanes
--------------------------------------------------------------------------------------------------------------------------------------------------------
Inspection........................ 4 $85 None.................. $340 per inspection 86 $29,240 per
cycle inspection cycle
--------------------------------------------------------------------------------------------------------------------------------------------------------
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
[[Page 20794]]
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), and
3. 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.
You can find our regulatory evaluation and the estimated costs of
compliance in the AD Docket.
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 AD:
The Boeing Company: Docket No. FAA-2010-0383; Directorate Identifier
2009-NM-214-AD.
Comments Due Date
(a) We must receive comments by June 7, 2010.
Affected ADs
(b) None.
Applicability
(c) This AD applies to The Boeing Company Model 747-100, 747-
100B, 747-100B SUD, 747-200B, 747-200C, 747-200F, 747-300, 747-400,
747SR, and 747SP series airplanes, certificated in any category; as
identified in Boeing Alert Service Bulletin 747-53A2750, dated
August 27, 2009.
Subject
(d) Air Transport Association (ATA) of America Code 53:
Fuselage.
Unsafe Condition
(e) This AD results from reports of cracks in overwing
intercostal webs between station (STA) 1160 and STA 1220. The
Federal Aviation Administration is issuing this AD to detect and
correct such cracking, which could grow and result in a severed
intercostal. If an intercostal is severed, cracks could develop in
the adjacent frame structure and skin, resulting in a rapid loss of
cabin pressure.
Compliance
(f) You are responsible for having the actions required by this
AD performed within the compliance times specified, unless the
actions have already been done.
Repetitive Inspections of the Overwing Intercostal Web
(g) Before the accumulation of 8,000 total flight cycles, or
within 1,500 flight cycles after the effective date of this AD,
whichever occurs later: Do a detailed inspection of the left-side
and right-side STAs 1160, 1180, 1200, and 1220 overwing intercostal
webs, and all applicable related investigative and corrective
actions, in accordance with the Accomplishment Instructions of
Boeing Alert Service Bulletin 747-53A2750, dated August 27, 2009,
except as required by paragraph (i) of this AD. Do all applicable
related investigative and corrective actions before further flight.
If no cracking is found during any detailed inspection, repeat the
inspection thereafter at intervals not to exceed 3,000 flight
cycles.
(h) For any airplane with an overwing intercostal web replaced
in accordance with Boeing Alert Service Bulletin 747-53A2750, dated
August 27, 2009: Within 6,000 flight cycles after the web was
replaced, do a detailed inspection of the replacement overwing
intercostal web, and do all applicable related investigative and
corrective actions, in accordance with the Accomplishment
Instructions of Boeing Alert Service Bulletin 747-53A2750, dated
August 27, 2009, except as required by paragraph (i) of this AD. Do
all applicable related investigative and corrective actions before
further flight. If no cracking is found during any detailed
inspection, repeat the inspection thereafter at intervals not to
exceed 3,000 flight cycles.
Exception to Service Bulletin
(i) If any cracking is found during any inspection required by
this AD, and Boeing Alert Service Bulletin 747-53A2750, dated August
27, 2009, specifies contacting Boeing for appropriate action: Before
further flight, repair the cracking using a method approved in
accordance with the procedures provided in paragraph (j) of this AD.
Alternative Methods of Compliance (AMOCs)
(j)(1) The Manager, Seattle 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. Send information to
ATTN: Ivan Li, Aerospace Engineer, Airframe Branch, ANM-120S, FAA,
Seattle Aircraft Certification Office (ACO), 1601 Lind Avenue, SW.,
Renton, Washington 98057-3356; telephone (425) 917-6437; fax (425)
917-6590. Information may be e-mailed to: [email protected].
(2) To request a different method of compliance or a different
compliance time for this AD, follow the procedures in 14 CFR 39.19.
Before using any approved AMOC on any airplane to which the AMOC
applies, notify your principal maintenance inspector (PMI) or
principal avionics inspector (PAI), as appropriate, or lacking a
principal inspector, your local Flight Standards District Office.
The AMOC approval letter must specifically reference this AD.
(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
that has been authorized by the Manager, Seattle ACO, to make those
findings. For a repair method to be approved, the repair must meet
the certification basis of the airplane, and the approval must
specifically refer to this AD.
Issued in Renton, Washington, on April 9, 2010.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 2010-9112 Filed 4-20-10; 8:45 am]
BILLING CODE 4910-13-P