AD 2017-09-10
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
Cracking of the front spar web inboard of pylon number 2 between front spar station inboard (FSSI) 655.75 and FSSI 660, which could lead to fuel leaks and a consequent fire.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Conduct repetitive detailed, ultrasonic, and high frequency eddy current inspections for cracking of the front spar web between FSSI 628 and FSSI 713. Repair any cracking found during inspections.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Within 6 months of the effective date of the AD.
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
The Boeing Company Model 747-400, 747-400D, and 747-400F 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 all The Boeing Company Model 747-400, 747-400D, and 747-400F airplanes. This AD was prompted by a report of a crack in the left wing front spar web, found following a fuel leak. This AD requires repetitive inspections for cracking of the front spar web, and repairs if necessary. We are issuing this AD to address the unsafe condition on these products.
Applicability Source Text
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(c) Applicability
This AD applies to all The Boeing Company Model 747-400, 747-
400D, and 747-400F airplanes, certificated in any category.
Document Text
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[Federal Register Volume 82, Number 98 (Tuesday, May 23, 2017)]
[Rules and Regulations]
[Pages 23509-23512]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2017-10257]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2016-9394; Directorate Identifier 2016-NM-162-AD;
Amendment 39-18872; AD 2017-09-10]
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 all The
Boeing Company Model 747-400, 747-400D, and 747-400F airplanes. This AD
was prompted by a report of a crack in the left wing front spar web,
found following a fuel leak. This AD requires repetitive inspections
for cracking of the front spar web, and repairs if necessary. We are
issuing this AD to address the unsafe condition on these products.
DATES: This AD is effective June 27, 2017.
The Director of the Federal Register approved the incorporation by
reference of a certain publication listed in this AD as of June 27,
2017.
ADDRESSES: For service information identified in this final rule,
contact Boeing Commercial Airplanes, Attention: Contractual & Data
Services (C&DS), 2600 Westminster Blvd., MC 110-SK57, Seal Beach, CA
90740-5600; telephone 562-797-1717; 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. It is also available on the Internet at <a href="http://www.regulations.gov">http://www.regulations.gov</a> by searching for and locating Docket No. FAA-2016-
9394.
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> by searching for and locating Docket No. FAA-2016-
9394; 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
[[Page 23510]]
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New
Jersey Avenue SE., Washington, DC 20590.
FOR FURTHER INFORMATION CONTACT: Bill Ashforth, Aerospace Engineer,
Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office
(ACO), 1601 Lind Avenue SW., Renton, WA 98057-3356; phone: 425-917-
6432; fax: 425-917-6590; email: <a href="/cdn-cgi/l/email-protection#42202b2e2e6c23312a242d30362a022423236c252d34"><span class="__cf_email__" data-cfemail="4a28232626642b39222c25383e220a2c2b2b642d253c">[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 all The Boeing Company
Model 747-400, 747-400D, and 747-400F airplanes. The NPRM published in
the Federal Register on December 2, 2016 (81 FR 86977) (``the NPRM'').
The NPRM was prompted by a report indicating that a fuel leak in one
airplane led to the discovery of a 13.4-inch crack in the left wing
front spar web inboard of pylon number 2 between front spar station
inboard (FSSI) 655.75 and FSSI 660. The NPRM proposed to require
repetitive detailed, ultrasonic, and high frequency eddy current
inspections for cracking of the front spar web between FSSI 628 and
FSSI 713, and repairs if necessary. We are issuing this AD to detect
and correct cracking in the front spar web, which could lead to fuel
leaks and a consequent fire.
Comments
We gave the public the opportunity to participate in developing
this AD. The following presents the comments received on the NPRM and
the FAA's response to each comment.
Support for the NPRM
Boeing and commenter Melanie Smith stated that they support the
NPRM.
Request To Update the Labor Costs
British Airways (BA), Cargolux Airlines (CLX), and KLM Royal Dutch
Airlines (KLM) all stated that the actual work-hours required to do the
mandated inspections are higher than the estimate listed in the NPRM.
They estimated the inspections actually take between 137 and 159 work-
hours, not the 55 work-hours stated in the NPRM.
We agree that the estimated work-hours should be increased. When
issuing a service bulletin, Boeing estimates work-hours under expected
conditions. As operators implement the service bulletin, they may find
the actual work-hours are higher or lower than estimated. We have
updated the Costs of Compliance section of this AD to reflect a
conservative estimate of 159 work-hours per inspection cycle.
Request To Change the Initial and Repetitive Compliance Times
BA, CLX, and KLM all requested that we change the initial and/or
repetitive compliance times to align with scheduled maintenance checks.
BA proposed to do time-limited alternative inspections in the most
critical web locations and to defer the majority of the web inspections
to coincide with longer planned maintenance checks. CLX requested that
we change the initial compliance time from 6 months to 24 months, and
that we change the repetitive inspection interval from 1,200 flight
cycles to 2,000 flight cycles. KLM requested that we extend the
repetitive inspection intervals for Model 747 freighters from 1,200
flight cycles to 1,800 flight cycles. Each of the commenters noted that
the actual work-hours are higher than estimated in the NPRM, and the
inspections would require additional downtime and costs if not done at
the same time as regularly scheduled maintenance. None of the
commenters provided engineering analyses to support their proposed
extended compliance times.
We disagree with the requests. In developing an appropriate
compliance time for this action, we considered the urgency associated
with the subject unsafe condition and the practical aspect of
accomplishing the required modification within a period of time that
corresponds to the normal scheduled maintenance for most affected
operators. Boeing is aware of the discrepancy in work-hours and is
developing a request for a global alternative method of compliance
(AMOC) to provide operators an alternative for both the areas of
inspection and the compliance times. In addition, operators have the
option of proposing an adjustment to the compliance times, supported by
appropriate engineering analyses, in accordance with the provisions of
paragraph (j) of this AD. We have not changed this final rule regarding
this issue.
Conclusion
We reviewed the relevant data, considered the comments received,
and determined that air safety and the public interest require adopting
this 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 for correcting the unsafe condition; and
<bullet> Do not add any additional burden upon the public than was
already proposed in the NPRM.
Related Service Information Under 1 CFR Part 51
We reviewed Boeing Alert Service Bulletin 747-57A2357, dated
September 12, 2016. The service information describes procedures for
repetitive detailed, ultrasonic, and high frequency eddy current
inspections, and repairs of cracking of the front spar web between FSSI
628 and FSSI 713. This service information is reasonably available
because the interested parties have access to it through their normal
course of business or by the means identified in the ADDRESSES section.
Costs of Compliance
We estimate that this AD affects 137 airplanes of U.S. registry. We
estimate the following costs to comply with this AD:
Estimated Costs
----------------------------------------------------------------------------------------------------------------
Cost on U.S.
Action Labor cost Parts cost Cost per product operators
----------------------------------------------------------------------------------------------------------------
Inspections...................... 159 work-hours x $0 $13,515 per $1,851,555 per
$85 per hour = inspection cycle. inspection cycle.
$13,515 per
inspection cycle.
----------------------------------------------------------------------------------------------------------------
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.
[[Page 23511]]
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):
2017-09-10 The Boeing Company: Amendment 39-18872; Docket No. FAA-
2016-9394; Directorate Identifier 2016-NM-162-AD.
(a) Effective Date
This AD is effective June 27, 2017.
(b) Affected ADs
None.
(c) Applicability
This AD applies to all The Boeing Company Model 747-400, 747-
400D, and 747-400F airplanes, certificated in any category.
(d) Subject
Air Transport Association (ATA) of America Code 57, Wings.
(e) Unsafe Condition
This AD was prompted by a report of a 13.4-inch crack in the
left wing front spar web inboard of pylon number 2 between front
spar station inboard (FSSI) 655.75 and FSSI 660, found following a
fuel leak. We are issuing this AD to detect and correct cracking in
the front spar web, which could lead to fuel leaks and a consequent
fire.
(f) Compliance
Comply with this AD within the compliance times specified,
unless already done.
(g) Repetitive Detailed, Ultrasonic, and High Frequency Eddy Current
Inspections
At the applicable time specified in paragraph 1.E.,
``Compliance,'' of Boeing Alert Service Bulletin 747-57A2357, dated
September 12, 2016, except as provided by paragraph (i) of this AD,
do detailed, ultrasonic, and high frequency eddy current inspections
for any cracking in the front spar web, in accordance with the
Accomplishment Instructions of Boeing Alert Service Bulletin 747-
57A2357, dated September 12, 2016. Repeat the inspections thereafter
at the applicable time specified in paragraph 1.E., ``Compliance,''
of Boeing Alert Service Bulletin 747-57A2357, dated September 12,
2016.
(h) Repair of Any Cracking
If any crack is found during any inspection required by
paragraph (g) of this AD, before further flight, repair using a
method approved in accordance with the procedures specified in
paragraph (j) of this AD. Thereafter, repeat the inspections
specified in paragraph (g) of this AD at all unrepaired areas.
(i) Service Information Exceptions
Where paragraph 1.E., ``Compliance,'' of Boeing Alert Service
Bulletin 747-57A2357, dated September 12, 2016, specifies a
compliance time ``after the original date of this service
bulletin,'' this AD requires compliance within the specified
compliance time after the effective date of this AD.
(j) Alternative Methods of Compliance (AMOCs)
(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 paragraph (k) of this AD.
Information may be emailed to: <a href="/cdn-cgi/l/email-protection#6e57432f2023433d0b0f1a1a020b432f2d21432f23212d433c0b1f1b0b1d1a1d2e080f0f40090118"><span class="__cf_email__" data-cfemail="271e0a66696a0a74424653534b420a6664680a666a68640a75425652425453546741464609404851">[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, modification, or alteration 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. To be approved, the
repair method, modification deviation, or alteration deviation must
meet the certification basis of the airplane, and the approval must
specifically refer to this AD.
(4) Except as required by paragraph (i) of this AD: For service
information that contains steps that are labeled as Required for
Compliance (RC), the provisions of paragraphs (j)(4)(i) and
(j)(4)(ii) of this AD apply.
(i) The steps labeled as RC, including substeps under an RC step
and any figures identified in an RC step, must be done to comply
with the AD. If a step or substep is labeled ``RC Exempt,'' then the
RC requirement is removed from that step or substep. An AMOC is
required for any deviations to RC steps, including substeps and
identified figures.
(ii) Steps not labeled as RC may be deviated from using accepted
methods in accordance with the operator's maintenance or inspection
program without obtaining approval of an AMOC, provided the RC
steps, including substeps and identified figures, can still be done
as specified, and the airplane can be put back in an airworthy
condition.
(k) Related Information
For more information about this AD, contact Bill Ashforth,
Aerospace Engineer, Airframe Branch, ANM-120S, FAA, Seattle Aircraft
Certification Office (ACO), 1601 Lind Avenue SW., Renton, WA 98057-
3356; phone: 425-917-6432; fax: 425-917-6590; email:
<a href="/cdn-cgi/l/email-protection#1d7f747171337c6e757b726f69755d7b7c7c337a726b"><span class="__cf_email__" data-cfemail="25474c49490b44564d434a57514d654344440b424a53">[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 747-57A2357, dated September
12, 2016.
(ii) Reserved.
(3) For service information identified in this AD, contact
Boeing Commercial Airplanes, Attention: Contractual & Data Services
(C&DS), 2600 Westminster Blvd., MC 110-SK57, Seal Beach, CA 90740-
5600; telephone 562-797-1717; 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.
[[Page 23512]]
(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 April 27, 2017.
Paul Bernado,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 2017-10257 Filed 5-22-17; 8:45 am]
BILLING CODE 4910-13-P
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