AD 2011-16-06
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | The Boeing Company | 747-400 Series | Airworthiness Directives; The Boeing Company Model 747-400 and - 400F Series Airplanes |
| aircraft | The Boeing Company | 747-400F Series | Airworthiness Directives; The Boeing Company Model 747-400 and - 400F Series Airplanes |
Unsafe Condition
Loss of bus control unit number 1 and generator control units numbers 1 and 2 while the airplane was on the ground, and multiple operator reports of cracked main equipment center (MEC) drip shields, which could result in water penetration into the MEC and loss of flight critical systems.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Inspect the MEC drip shields for cracks and holes, repair as necessary, install a fiberglass reinforcing overcoat, and for certain airplanes, install stiffening panels to the MEC drip shields.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Within 24 months of the effective date (September 9, 2011).
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
The Boeing Company Model 747-400 and -400F Series Airplanes.
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 the products listed above. This AD requires a general visual inspection for cracks and holes of the main equipment center (MEC) drip shields, and repairs if necessary; installation of a fiberglass reinforcing overcoat; and, for certain airplanes, installation of stiffening panels to the MEC drip shields. This AD was prompted by a report of a loss of bus control unit number 1 and generator control units numbers 1 and 2 while the airplane was on the ground, and multiple operator reports of cracked MEC drip shields. We are issuing this AD to prevent water penetration into the MEC, which could result in the loss of flight critical systems.
Document Text
Show stored source text (verify against official source)
[Federal Register Volume 76, Number 151 (Friday, August 5, 2011)]
[Rules and Regulations]
[Pages 47427-47430]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2011-19828]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2011-0041; Directorate Identifier 2010-NM-227-AD;
Amendment 39-16764; AD 2011-16-06]
RIN 2120-AA64
Airworthiness Directives; The Boeing Company Model 747-400 and -
400F Series Airplanes
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final rule.
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SUMMARY: We are adopting a new airworthiness directive (AD) for the
products listed above. This AD requires a general visual inspection for
cracks and holes of the main equipment center (MEC) drip shields, and
repairs if necessary; installation of a fiberglass reinforcing
overcoat; and, for certain airplanes, installation of stiffening panels
to the MEC drip shields. This AD was prompted by a report of a loss of
bus control unit number 1 and generator control units numbers 1 and 2
while the airplane was on the ground, and multiple operator reports of
cracked
[[Page 47428]]
MEC drip shields. We are issuing this AD to prevent water penetration
into the MEC, which could result in the loss of flight critical
systems.
DATES: This AD is effective September 9, 2011.
The Director of the Federal Register approved the incorporation by
reference of a certain publication listed in the AD as of September 9,
2011.
ADDRESSES: For service information identified in this AD, contact
Boeing Commercial Airplanes, Attention: Data & Services Management,
P.O. Box 3707, MC 2H-65, Seattle, Washington 98124-2207; phone: 206-
544-5000, extension 1; fax: 206-766-5680; e-mail: <a href="/cdn-cgi/l/email-protection#b1dcd49fd3ded4d2dedcf1d3ded4d8dfd69fd2dedc"><span class="__cf_email__" data-cfemail="0a676f2468656f6965674a68656f63646d24696567">[email protected]</span></a>;
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: Francis Smith, Aerospace Engineer,
Cabin Safety & Environmental Systems Branch, ANM-150S, FAA, Seattle
Aircraft Certification Office (ACO), 1601 Lind Avenue, SW., Renton,
Washington 98057-3356; phone: 425-917-6596; fax: 425-917-6590; e-mail:
<a href="/cdn-cgi/l/email-protection#632511020d000a104d300e0a170b230502024d040c15"><span class="__cf_email__" data-cfemail="7731051619141e0459241a1e031f3711161659101801">[email protected]</span></a>.
SUPPLEMENTARY INFORMATION:
Discussion
We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR
part 39 to include an airworthiness directive (AD) that would apply to
the specified products. That NPRM published in the Federal Register on
February 10, 2011 (76 FR 7513). The NPRM proposed a general visual
inspection for cracks and holes of the main equipment center (MEC) drip
shields, and repairs if necessary; installation of a fiberglass
reinforcing overcoat; and, for certain airplanes, installation of
stiffening panels to the MEC drip shields.
Comments
We gave the public the opportunity to participate in developing
this AD. The following presents the comments received on the proposal
and the FAA's response to each comment.
Request To Reference Latest Service Bulletin Revision
Both UPS and Boeing requested that we revise the NPRM to require
that actions be done in accordance with Boeing Alert Service Bulletin
747-25A3588, Revision 1, dated April 7, 2011. The NPRM referred to
Boeing Alert Service Bulletin 747-25A3588, dated July 19, 2010, as the
appropriate source of service information for the required actions.
We agree. Boeing Alert Service Bulletin 747-25A3588, Revision 1,
dated April 7, 2011, removes airplane RT101 from this service
information effectivity and provides operators with additional material
options. The procedures remain unchanged. We revised paragraphs (c),
(g), (g)(1), and (g)(2) in this final rule to refer to Boeing Alert
Service Bulletin 747-25A3588, Revision 1, dated April 7, 2011. We added
new paragraph (h) to the final rule to give credit for actions done
before the effective date of this AD in accordance with Boeing Alert
Service Bulletin 747-25A3588, dated July 19, 2010, and re-identified
subsequent paragraphs accordingly.
Request To Extend the Compliance Time
UPS stated concern with Boeing's ability to provide adequate
modification kits to all affected operators within the proposed 24-
month compliance time. UPS justified its concern by stating that the
NPRM acknowledges it would affect an estimated 41 airplanes of U.S.
registry. UPS stated that worldwide, there are more than 150 Model 747-
400F airplanes that are affected by the referenced service information
and many may attempt to accomplish this modification within the 24-
month compliance time. At the time, Boeing had indicated it had
materials available to produce only 6 kits, and will require 190 days
lead time to replenish the stock. As the referenced service information
specifies to install the parts provided in the kit by part number, an
alternative method of compliance (AMOC) would be required for any
operators needing to fabricate their own modification parts from raw
materials, if Boeing is unable to provide the required modification
kits in a timely basis for the proposed installation.
We infer that UPS is requesting that we extend the proposed
compliance time. Boeing Alert Service Bulletin 747-25A3588, dated July
19, 2010; and Revision 1, dated April 7, 2011; were both coordinated
between Boeing and the FAA. Proposed methods of compliance and the
compliance time were weighed versus uncorrected risks in determining an
acceptable and feasible corrective action. Boeing is most familiar with
its ability to supply operators with instructions and kits to meet AD
compliance, and determined it would be capable of reasonably achieving
a 24-month compliance time with the proposed methods, when both Boeing
Alert Service Bulletin 747-25A3588, dated July 19, 2010; and Revision
1, dated April 7, 2011; were drafted and approved. Although kits may
not be available immediately for every airplane, Boeing has advised us
that it is capable of creating and delivering additional kits for
operators to use within the AD compliance time.
Once we issue this AD, any person may request approval of an AMOC
under the provisions of paragraph (i) of this AD. We have not changed
this AD in this regard.
Conclusion
We reviewed the relevant data, considered the comments received,
and determined that air safety and the public interest require adopting
the AD with the change described previously. We also determined that
this change will not increase the economic burden on any operator or
increase the scope of the AD.
Costs of Compliance
We estimate that this AD affects 41 airplanes of U.S. registry.
We estimate the following costs to comply with this AD:
[[Page 47429]]
Estimated Costs
----------------------------------------------------------------------------------------------------------------
Cost per Cost on U.S.
Action Labor cost Parts cost product operators
----------------------------------------------------------------------------------------------------------------
Inspection and installation: 20 work-hours x $85 $1,109............... $2,809 $67,416
Groups 1, 3 (24 airplanes). per hour = $1,700.
Inspection and installation: Group 17 work-hours x $85 Negligible........... 1,445 24,565
2 (17 airplanes). per hour = $1,445.
----------------------------------------------------------------------------------------------------------------
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 airplane
----------------------------------------------------------------------------------------------------------------
Hole repair.......................... 1 work-hour x $85 per Negligible............. $85 per hole.
hour = $85 per hole.
----------------------------------------------------------------------------------------------------------------
According to the manufacturer, some of the costs of this AD may be
covered under warranty, thereby reducing the cost impact on affected
individuals. We do not control warranty coverage for affected
individuals. As a result, we have included all costs in our cost
estimate.
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):
2011-16-06 The Boeing Company: Amendment 39-16764; Docket No. FAA-
2011-0041; Directorate Identifier 2010-NM-227-AD.
Effective Date
(a) This AD is effective September 9, 2011.
Affected ADs
(b) None.
Applicability
(c) This AD applies to The Boeing Company Model 747-400 and -
400F series airplanes, certificated in any category, as identified
in Boeing Alert Service Bulletin 747-25A3588, Revision 1, dated
April 7, 2011.
Subject
(d) Joint Aircraft System Component (JASC)/Air Transport
Association (ATA) of America Code 25: Equipment/Furnishings.
Unsafe Condition
(e) This AD was prompted by a report of a loss of bus control
unit number 1 and generator control units numbers 1 and 2 while the
airplane was on the ground, and multiple operator reports of cracked
main equipment center (MEC) drip shields. We are issuing this AD to
prevent water penetration into the MEC, which could result in the
loss of flight critical systems.
Compliance
(f) Comply with this AD within the compliance times specified,
unless already done.
Inspection
(g) Within 24 months after the effective date of this AD, do the
actions specified in paragraph (g)(1) or (g)(2) of this AD, as
applicable, in accordance with the Accomplishment Instructions of
Boeing Alert Service Bulletin 747-25A3588, Revision 1, dated April
7, 2011.
(1) For Group 1 and Group 3 airplanes, as identified in Boeing
Alert Service Bulletin 747-25A3588, Revision 1, dated April 7, 2011:
Do a general visual inspection of the MEC drip shield to detect
cracking and holes, do all applicable repairs, and install the MEC
drip shield panel stiffeners and the fiberglass reinforcing overcoat
to the MEC drip shield, in accordance with the Accomplishment
Instructions of Boeing Alert Service Bulletin 747-25A3588, Revision
1, dated April 7, 2011. Do all applicable repairs before further
flight.
(2) For Group 2 airplanes, as identified in Boeing Alert Service
Bulletin 747-25A3588, Revision 1, dated April 7, 2011: Do a general
visual inspection of the MEC drip shield to detect cracking and
holes, do all applicable repairs, and install the fiberglass
reinforcing overcoat to the MEC drip shield, in accordance with the
Accomplishment Instructions of Boeing Alert Service Bulletin 747-
25A3588, Revision 1, dated April 7, 2011. Do all applicable repairs
before further flight.
[[Page 47430]]
Credit for Actions Accomplished in Accordance With Previous Service
Information
(h) Accomplishing the actions required in paragraph (g) of this
AD before the effective date of this AD in accordance with Boeing
Alert Service Bulletin 747-25A3588, dated July 19, 2010, is
considered acceptable for compliance with the corresponding actions
specified in this AD.
Alternative Methods of Compliance (AMOCs)
(i)(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. 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. Information may be e-mailed to: <a href="/cdn-cgi/l/email-protection#b28b9ff3fcff9fe1d7d3c6c6ded79ff3f1fd9ff3fffdf19fe0d7c3c7d7c1c6c1f2d4d3d39cd5ddc4"><span class="__cf_email__" data-cfemail="a99084e8e7e484faccc8ddddc5cc84e8eae684e8e4e6ea84fbccd8dcccdadddae9cfc8c887cec6df">[email protected]</span></a>.
(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.
Related Information
(j) For more information about this AD, contact Francis Smith,
Aerospace Engineer, Cabin Safety & Environmental Systems Branch,
ANM-150S, FAA, Seattle Aircraft Certification Office (ACO), 1601
Lind Avenue, SW., Renton, Washington 98057-3356; phone: 425-917-6596
; fax: 425-917-6590; e-mail: <a href="/cdn-cgi/l/email-protection#521420333c313b217c013f3b263a123433337c353d24"><span class="__cf_email__" data-cfemail="246256454a474d570a77494d504c644245450a434b52">[email protected]</span></a>.
Material Incorporated by Reference
(k) You must use Boeing Alert Service Bulletin 747-25A3588,
Revision 1, dated April 7, 2011, to do the actions required by this
AD, unless the AD specifies otherwise.
(1) The Director of the Federal Register approved the
incorporation by reference of this service information under 5
U.S.C. 552(a) and 1 CFR part 51.
(2) For service information identified in this AD, contact
Boeing Commercial Airplanes, Attention: Data & Services Management,
P.O. Box 3707, MC 2H-65, Seattle, Washington 98124-2207; phone: 206-
544-5000, extension 1; fax: 206-766-5680; e-mail:
<a href="/cdn-cgi/l/email-protection#6508004b070a00060a0825070a000c0b024b060a08"><span class="__cf_email__" data-cfemail="6c0109420e03090f03012c0e030905020b420f0301">[email protected]</span></a>; Internet: <a href="https://www.myboeingfleet.com">https://www.myboeingfleet.com</a>.
(3) You may review copies of the 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.
(4) You may also review copies of the 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/code_of_federal_regulations/ibr_locations.html">http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html</a>.
Issued in Renton, Washington, on July 26, 2011.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 2011-19828 Filed 8-4-11; 8:45 am]
BILLING CODE 4910-13-P
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