AD 2013-26-04
final rule
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | The Boeing Company | 747-400 Series | Airworthiness Directives; The Boeing Company Airplanes |
| aircraft | The Boeing Company | 747-400D Series | Airworthiness Directives; The Boeing Company Airplanes |
| aircraft | The Boeing Company | 747-400F Series | Airworthiness Directives; The Boeing Company Airplanes |
Unsafe Condition
Water leakage into the main deck cargo wire integration unit (WIU) due to disbonded seams in the aft main equipment center (MEC) drip shield gutter.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Clean the aft MEC drip shield gutter; perform a one-time general visual inspection for disbonded seams and repair if necessary; install a fiberglass reinforcement overcoat to the underside of the bonded seams of the aft MEC drip shield gutters.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Before further flight
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
The Boeing Company Model 747-400, -400D, 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 certain The Boeing Company Model 747-400, -400D, and -400F series airplanes. This AD was prompted by a report of water leakage into the main deck cargo wire integration unit (WIU). The water flowed from the main deck floor panels, through disbonded seams in the aft main equipment center (MEC) drip shield gutter, then onto the WIU. This AD requires cleaning the aft MEC drip shield gutter; and doing a one-time general visual inspection for disbonded seams, and repair if necessary. This AD also requires installing a fiberglass reinforcement overcoat to the underside of the bonded seams of the aft MEC drip shield gutters. We are issuing this AD to prevent water penetration into the MEC, which could result in the loss of flight critical systems.
Applicability Source Text
Show captured applicability text from the source AD
(c) Applicability
This AD applies to The Boeing Company Model 747-400, -400D, and
-400F series airplanes, certificated in any category, as identified
in Boeing Alert Service Bulletin 747-25A3613, dated June 22, 2012.
Document Text
Show stored source text (verify against official source)
[Federal Register Volume 78, Number 250 (Monday, December 30, 2013)]
[Rules and Regulations]
[Pages 79289-79292]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2013-30469]
-----------------------------------------------------------------------
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2013-0304; Directorate Identifier 2013-NM-005-AD;
Amendment 39-17713; AD 2013-26-04]
RIN 2120-AA64
Airworthiness Directives; The Boeing Company Airplanes
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final rule.
-----------------------------------------------------------------------
SUMMARY: We are adopting a new airworthiness directive (AD) for certain
The Boeing Company Model 747-400, -400D, and -400F series airplanes.
This AD was prompted by a report of water leakage into the main deck
cargo wire integration unit (WIU). The water flowed from the main deck
floor panels, through disbonded seams in the aft main equipment center
(MEC) drip shield gutter, then onto the WIU. This AD requires cleaning
the aft MEC drip shield gutter; and doing a one-time general visual
inspection for disbonded seams, and repair if necessary. This AD also
requires installing a fiberglass reinforcement overcoat to the
underside of the bonded seams of the aft MEC drip shield gutters. 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 February 3, 2014.
The Director of the Federal Register approved the incorporation by
reference of a certain publication listed in this AD as of February 3,
2014.
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; telephone 206-
544-5000, extension 1; fax 206-766-5680; Internet <a href="https://www.myboeingfleet.com">https://www.myboeingfleet.com</a>. You may view this referenced service information
at the FAA, Transport Airplane Directorate, 1601 Lind Avenue SW.,
Renton, WA. For information on the availability of this material at the
FAA, call 425-227-1221.
[[Page 79290]]
Examining the AD Docket
You may examine the AD docket on the Internet at <a href="http://www.regulations.gov/#!docketDetail">http://www.regulations.gov/#!docketDetail</a>;D=FAA-2013-0304; 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 Docket
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 and Environmental Systems Branch, ANM-150S, FAA, Seattle
Aircraft Certification Office, 1601 Lind Avenue SW., Renton, WA 98057-
3356; phone: (425) 917-6596; fax: (425) 917-6590; email
<a href="/cdn-cgi/l/email-protection#117763707f7278623f627c786579517770703f767e67"><span class="__cf_email__" data-cfemail="e58397848b868c96cb96888c918da5838484cb828a93">[email protected]</span></a>.
SUPPLEMENTARY INFORMATION:
Discussion
We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR
part 39 by adding an AD that would apply to the specified products. The
NPRM published in the Federal Register on April 11, 2013 (78 FR 21571).
The NPRM proposed to require removing the cargo liner support; cleaning
the aft MEC drip shield gutter; and doing a one-time general visual
inspection for disbonded seams, and repair if necessary. The NPRM also
proposed to require installing a fiberglass reinforcement overcoat to
the top surface of the aft MEC drip shield gutters and installing the
cargo liner support.
Comments
We gave the public the opportunity to participate in developing
this AD. The following presents the comments received on the proposal
(78 FR 21571, April 11, 2013) and the FAA's response to each comment.
Request To Clarify Area for Installing Fiberglass Reinforcement
Overcoat
United Airlines (UAL), British Airways (BAB), and Boeing asked that
the area for installing the fiberglass reinforcement overcoat, as
specified in paragraph (g)(2) of the NPRM (78 FR 21571, April 11,
2013), be changed for clarification. Boeing stated that the description
of the area is not accurate. UAL stated that the location for
installing the fiberglass reinforcement overcoat ``to the top surface''
of the aft main equipment center (MEC) drip shield gutters, as
specified in paragraph (g)(2) of the NPRM, is different than the area
specified in Boeing Alert Service Bulletin 747-25A3613, dated June 22,
2012. UAL noted that the referenced service information specifies
installing the fiberglass reinforcement overcoat ``to the underside
surface'' of the aft MEC drip shield gutters. BAB stated that Figure 4,
Sheets 2 and 3 of Boeing Alert Service Bulletin 747-25A3613, dated June
22, 2012, show the installation from underneath the aft MEC drip shield
gutter; and added that Figure 4, Step 3, Note (c) specifies to
``Install the prepared BMS 9-3 fiberglass impregnated fabric to the
underside of the bonded seams.''
We agree with the commenters' requests to clarify the location for
installing the fiberglass reinforcement overcoat. Figure 4, Sheets 2
and 3 of Boeing Alert Service Bulletin 747-25A3613, dated June 22,
2012, provide clarity. Therefore, we have changed the SUMMARY section
and paragraph (g)(2) of this final rule to specify the location in
Figure 4, Step 3, Note (c) for installation of the fiberglass
reinforcement overcoat to ``the underside of the bonded seams.''
Request To Clarify the Unsafe Condition
Boeing asked that we clarify the second sentence of the reason for
the unsafe condition, as specified in the SUMMARY section and paragraph
(e) of the NPRM (78 FR 21571, April 11, 2013), from ``The water flowed
from the drip shield through disbonded floor seams into the aft . . .''
to ``The water flowed from the main deck floor panels, through
disbonded seams in the aft . . ..'' Boeing stated that, as specified,
the description is not accurate based on reports received from
operators.
We agree with the commenter's request for the reason provided. We
have clarified the reason for the unsafe condition in the SUMMARY
section and paragraph (e) of this final rule accordingly.
Request To Add a Note Allowing Different Access for Different
Structural Configurations
UAL asked that we include a note specifying that accessing certain
areas to accomplish the actions proposed in the NPRM (78 FR 21571,
April 11, 2013) may vary due to configuration differences. UAL stated
that including such a note would save operators a lot of time dealing
with variances in the quantity of fasteners called out in the service
information versus those on the airplane. UAL noted that for AD 2012-
15-10, Amendment 39-17139 (77 FR 46943, August 7, 2012), regarding the
MEC drip shield, it already has six alternative methods of compliance
(AMOCs) due to these variances.
We agree with the commenter's request. Boeing Alert Service
Bulletin 747-25A3613, dated June 22, 2012, does not identify all
possible structural configurations of the affected airplanes when
gaining access to the repair area. The resulting AMOC requests and
review of those requests creates a high volume of work and time, which
impacts both operators and the FAA. These deviations do not directly
impact the specified corrective actions.
We have changed the language in the SUMMARY and Costs of Compliance
sections, as well as paragraphs (g)(1) and (g)(2) of this final rule,
to remove the reference to the cargo liner support. We have also added
a sentence to the introductory text of paragraph (g) of this AD to
specify that accomplishing paragraphs 3.B.1. and 3.B.4. of the
Accomplishment Instructions of Boeing Alert Service Bulletin 747-
25A3613, dated June 22, 2012, is optional.
Request To Ground All Affected Airplanes
One anonymous commenter reiterated the actions proposed by the NPRM
(78 FR 21571, April 11, 2013), and stated that he found it troubling
that we are asking the public ``(presumably experts)'' to comment on a
safety issue with a Boeing design, yet these airplanes have not been
grounded until the notice and comment period ends. The commenter added
that The Boeing Company must comply with strict FAA guidelines, as
outlined by the Federal Aviation Act of 1958 (49 U.S.C. App. 1301 et
seq.). The commenter noted that, crucial to this particular
airworthiness directive, the FAA encourages the development of ``next
wave'' civil aeronautics, new aviation technology, and continued safety
enhancements of all domestically flown commercial airplanes. The
commenter also added that participation in the notice and comment
period is in line with the FAA's mission. The commenter concluded that
Congress charges the FAA with promoting safe flight of civil airplanes
in air commerce by prescribing regulations for practices, methods, and
procedures.
We infer that the commenter finds we lack sufficient information to
determine a compliance time for correcting this unsafe condition before
receiving public comment. We also infer the commenter concluded that
affected airplanes are exposed to an unacceptably high risk requiring
immediate action to remove
[[Page 79291]]
them from service until more information is obtained through public
comments. We do not agree. Before posting an NPRM for public comment,
we must perform an investigative review of the subject concern or
unsafe condition first obtained from operator reports. After gathering
this information from operators and the manufacturer, we make a
determination on the associated risk of the unsafe condition and
coordinate with the manufacturer on a compliance time and corrective
action for all affected airplanes. Airplanes are grounded in rare cases
where it is determined that the unsafe condition has an immediate risk
to public safety. The unsafe condition in this AD does not meet these
criteria.
Additionally, agencies welcome and consider all relevant rulemaking
comments received from the public. The purpose of public participation
is more to obtain comments from interested parties, not necessarily
``experts'' in the aviation industry. This is in line with the
democratic, legal, and management principles behind good government and
effective rulemaking. Further information on these principles can be
found on the Internet at <a href="http://www.regulations.gov">http://www.regulations.gov</a>, under ``docs/
Factsheet--Public--Comments--Make--a--Difference.pdf.'' We have made no
change to this final rule in this regard.
Conclusion
We reviewed the relevant data, considered the comments received,
and determined that air safety and the public interest require adopting
this AD with the changes described previously. We also determined that
these changes will not increase the economic burden on any operator or
increase the scope of this AD.
Costs of Compliance
We estimate that this AD affects 79 airplanes of U.S. registry.
We estimate the following costs to comply with this AD:
Estimated Costs
----------------------------------------------------------------------------------------------------------------
Cost per Cost on U.S.
Action Labor cost Parts cost product operators
----------------------------------------------------------------------------------------------------------------
Clean gutter, inspect................. 1 work-hour x $85 per $0 $85 $6,715
hour = $85.
Install fiberglass reinforcement...... 1 work-hour x $85 per 100 185 14,615
hour = $85.
----------------------------------------------------------------------------------------------------------------
We have received no definitive data that would enable us to provide
cost estimates for the on-condition actions 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):
2013-26-04 The Boeing Company: Amendment 39-17713; Docket No. FAA-
2013-0304; Directorate Identifier 2013-NM-005-AD.
(a) Effective Date
This AD is effective February 3, 2014.
(b) Affected ADs
None.
(c) Applicability
This AD applies to The Boeing Company Model 747-400, -400D, and
-400F series airplanes, certificated in any category, as identified
in Boeing Alert Service Bulletin 747-25A3613, dated June 22, 2012.
(d) Subject
Joint Aircraft System Component (JASC)/Air Transport Association
(ATA) of America Code 25: Equipment/Furnishings.
(e) Unsafe Condition
This AD was prompted by a report of water leakage into the main
deck cargo wire integration unit (WIU). The water flowed from the
main deck floor panels, through disbonded seams in the aft main
equipment center (MEC) drip shield gutter, then onto the WIU. We are
issuing this AD to prevent water penetration into the MEC, which
could result in the loss of flight critical systems.
(f) Compliance
Comply with this AD within the compliance times specified,
unless already done.
(g) Removal/Cleaning/Inspection/Repair if Necessary/Installations
Within 24 months after the effective date of this AD: Do the
actions specified in paragraphs (g)(1) and (g)(2) of this AD, in
accordance with the Accomplishment Instructions of Boeing Alert
Service Bulletin 747-25A3613, dated June 22, 2012. Accomplishing
paragraphs 3.B.1. and 3.B.4. of the Accomplishment Instructions of
Boeing Alert Service Bulletin 747-25A3613, dated June 22, 2012, is
optional.
[[Page 79292]]
(1) Clean the aft MEC drip shield gutter, and do a general
visual inspection for disbonded seams; repair before further flight
if any seam disbonding is found.
(2) Install a fiberglass reinforcement overcoat to the underside
of the bonded seams of the aft MEC drip shield gutters.
(h) Alternative Methods of Compliance (AMOCs)
(1) The Manager, Seattle Aircraft Certification Office (ACO),
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 paragraph (i) of this AD. Information may be
emailed to: <a href="/cdn-cgi/l/email-protection#a89185e9e6e585fbcdc9dcdcc4cd85e9ebe785e9e5e7eb85facdd9ddcddbdcdbe8cec9c986cfc7de"><span class="__cf_email__" data-cfemail="af9682eee1e282fccacedbdbc3ca82eeece082eee2e0ec82fdcadedacadcdbdcefc9cece81c8c0d9">[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.
(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, 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.
(i) Related Information
For more information about this AD, contact Francis Smith,
Aerospace Engineer, Cabin Safety and Environmental Systems Branch,
ANM-150S, FAA, Seattle Aircraft Certification Office, 1601 Lind
Avenue SW., Renton, WA 98057-3356; phone: (425) 917-6596; fax: (425)
917-6590; email <a href="/cdn-cgi/l/email-protection#d3b5a1b2bdb0baa0fda0bebaa7bb93b5b2b2fdb4bca5"><span class="__cf_email__" data-cfemail="6d0b1f0c030e041e431e000419052d0b0c0c430a021b">[email protected]</span></a>.
(j) 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 747-25A3613, dated June 22,
2012.
(ii) Reserved.
(3) For service information identified in this AD, contact
Boeing Commercial Airplanes, Attention: Data & Services Management,
P.O. Box 3707, MC 2H-65, Seattle, WA 98124-2207; telephone 206-544-
5000, extension 1; fax 206-766-5680; Internet <a href="https://www.myboeingfleet.com">https://www.myboeingfleet.com</a>.
(4) You may view this service information at the FAA, Transport
Airplane Directorate, 1601 Lind Avenue SW., Renton, WA. 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 December 13, 2013.
John P. Piccola,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 2013-30469 Filed 12-27-13; 8:45 am]
BILLING CODE 4910-13-P
Source: Official FAA Source ↗
Retrieved: Apr 4, 2026
Rights: U.S. Government Public Domain
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