AD 2012-11-03
final rule
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | The Boeing Company | 777-200 Series | Airworthiness Directives; The Boeing Company Airplanes |
| aircraft | The Boeing Company | 777-200LR Series | Airworthiness Directives; The Boeing Company Airplanes |
| aircraft | The Boeing Company | 777-300 Series | Airworthiness Directives; The Boeing Company Airplanes |
| aircraft | The Boeing Company | 777-300ER Series | Airworthiness Directives; The Boeing Company Airplanes |
| aircraft | The Boeing Company | 777F Series | Airworthiness Directives; The Boeing Company Airplanes |
Unsafe Condition
Retaining cross bolt hardware not fully engaged into the fuse pins of the forward trunnion lower housing of the main landing gear (MLG), which could result in an incorrect MLG emergency landing break-away sequence.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Inspect the fuse pin cross bolts and fuse pins of the left and right MLG forward trunnion lower housing to verify correct installation and no missing fuse pins. Replace the fuse pins if necessary.
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 777 airplanes, as identified in Boeing Alert Service Bulletin 777-57A0090, dated August 24, 2011.
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 777 airplanes. This AD was prompted by four reports of retaining cross bolt hardware not fully engaged into the fuse pins of the forward trunnion lower housing of the main landing gear (MLG), which could result in an incorrect MLG emergency landing break-away sequence. This AD requires a detailed inspection of the fuse pin cross bolts and fuse pins of the left and right MLG forward trunnion lower housing to verify that the cross bolts are correctly installed and that there are no missing fuse pins, and replacement of the fuse pins if necessary. We are issuing this AD to prevent an incorrect emergency landing MLG break-away sequence, which could result in puncturing of the wing box and consequent fuel leaks and an airplane fire. Failure of the fuse pins could also result in a possible landing gear collapse causing a runway excursion during take-off or landing.
Applicability Source Text
Show captured applicability text from the source AD
(c) Applicability
This AD applies to The Boeing Company Model 777-200, -200LR, -
300, -300ER, and 777F series airplanes, certificated in any
category, as identified in Boeing Alert Service Bulletin 777-
57A0090, dated August 24, 2011.
Document Text
Show stored source text (verify against official source)
[Federal Register Volume 77, Number 107 (Monday, June 4, 2012)]
[Rules and Regulations]
[Pages 32889-32892]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2012-12910]
-----------------------------------------------------------------------
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2011-1320; Directorate Identifier 2011-NM-208-AD;
Amendment 39-17066; AD 2012-11-03]
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 all The
Boeing Company Model 777 airplanes. This AD was prompted by four
reports of retaining cross bolt hardware not fully engaged into the
fuse pins of the forward trunnion lower housing of the main landing
gear (MLG), which could result in an incorrect MLG emergency landing
break-away sequence. This AD requires a detailed inspection of the fuse
pin cross bolts and fuse pins of the left and right MLG forward
trunnion lower housing to verify that the cross bolts are correctly
installed and that there are no missing fuse pins, and replacement of
the fuse pins if necessary. We are issuing this AD to prevent an
incorrect emergency landing MLG break-away sequence, which could result
in puncturing of the wing box and consequent fuel leaks and an airplane
fire. Failure of the fuse pins could also result in a possible landing
gear collapse causing a runway excursion during take-off or landing.
DATES: This AD is effective July 9, 2012.
The Director of the Federal Register approved the incorporation by
reference of a certain publication listed in the AD as of July 9, 2012.
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; email: <a href="/cdn-cgi/l/email-protection#d9b4bcf7bbb6bcbab6b499bbb6bcb0b7bef7bab6b4"><span class="__cf_email__" data-cfemail="016c642f636e64626e6c41636e64686f662f626e6c">[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,
[[Page 32890]]
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: James Sutherland, Aerospace Engineer,
Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office
(ACO), 1601 Lind Avenue SW., Renton, Washington 98057-3356; phone: 425-
917-6533; fax: 425-917-6590; email: <a href="/cdn-cgi/l/email-protection#f9b398949c8ad7aa8c8d919c8b9598979db99f9898d79e968f"><span class="__cf_email__" data-cfemail="e6ac878b8395c8b593928e83948a878882a6808787c8818990">[email protected]</span></a>.
SUPPLEMENTARY INFORMATION:
Discussion
We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR
part 39 to include an AD that would apply to the specified products.
That NPRM published in the Federal Register on December 15, 2011 (76 FR
77937). That NPRM proposed to require a detailed inspection of the fuse
pin cross bolts and fuse pins of the forward trunnion lower housing of
the left and right MLG to verify that the cross bolts are correctly
installed and that there are no missing fuse pins, and replacing all
fuse pins in the MLG forward trunnion upper and lower housing with new
fuse pins if necessary.
Comments
We gave the public the opportunity to participate in developing
this AD. The following presents the comments received on the proposal
(76 FR 77937, December 15, 2011) and the FAA's response to each
comment.
Support for the NPRM (76 FR 77937, December 15, 2011)
United Airlines stated it concurs with the proposed rule (76 FR
77937, December 15, 2011) to inspect for the correct installation of
the cross bolts and the fuse pins to ensure a high level of safety for
the 777 fleet.
Thomas Hayden Barnes stated that he supports efforts to ensure
airline safety and the proposed rule (76 FR 77937, December 15, 2011).
Request To Clarify Fuse Pin Replacement
American Airlines (American) and FedEx requested clarification as
to whether the NPRM (76 FR 77937, December 15, 2011) requires changing
all fuse pins on both left and right MLG even if the discrepant
condition is only found on one side of the airplane MLG.
We agree to clarify the fuse pin replacement by changing paragraph
(g) of the final rule to read, in part: ``If any cross bolt of the MLG
forward trunnion lower housing is not installed correctly, or if any
fuse pin of the MLG forward trunnion lower housing is missing: Before
further flight, replace all fuse pins in the MLG forward trunnion upper
and lower housing on the side, or sides of the airplane, where the
missing or incorrectly installed fuse pin/pins were discovered * * *.''
Request To Use Maintenance Pits and Clarify Procedure
American requested that the NPRM (76 FR 77937, December 15, 2011)
permit the use of maintenance pits in lieu of jacking the airplane, as
specified in Boeing Alert Service Bulletin 777-57A0090, dated August
24, 2011. American stated that it is acceptable to stabilize the
airplane on jacks and lower maintenance pits until the wheels do not
touch the surface, and accomplishes the same effect of unloading the
airplane weight from the trunnion for the purposes of changing the fuse
pins.
American also noted that the phrase ``until the wheels are just off
the ground'' in Part 2 of the Accomplishment Instructions of Boeing
Alert Service Bulletin 777-57A0090, dated August 24, 2011, might be
construed to be a dimension without tolerance.
We agree that the use of lowered maintenance pits to unload the MLG
does have the same effect as lifting. We also agree that the meaning of
the phrase ``just off the ground'' is a dimension without tolerance. We
have changed paragraph (g) of the final rule to specify that step 1 in
Part 2 of paragraph 3.B. of the Accomplishment Instructions of Boeing
Alert Service Bulletin 777-57A0090, dated August 24, 2011, is not
considered regulatory for the purposes of this AD.
Request To Change Applicability
Boeing and FedEx requested that the applicability of the NPRM (76
FR 77937, December 15, 2011) list only the airplanes specified in
Boeing Alert Service Bulletin 777-57A0090, dated August 24, 2011.
Boeing stated that airplanes not listed in this service information
have been inspected during production to ensure they do not have the
unsafe condition. FedEx stated that it currently flies 6 aircraft that
are not listed in the NPRM, and is adding new aircraft to its fleet,
none of which will be listed in the NPRM.
We agree. The intent of the AD is to ensure that inspections are
done on airplanes on which Boeing was unable to confirm that the cross
bolts are installed correctly and on which there are no missing fuse
pins. We have changed paragraph (c) of the final rule to apply to the
airplanes identified in Boeing Alert Service Bulletin 777-57A0090,
dated August 24, 2011.
Additional Change Made to This Final Rule
We have removed Note 1 that followed paragraph (g) in the NPRM (76
FR 77937, December 15, 2011) from the final rule. That information is
contained in Note 7 of the Accomplishment Instructions of Boeing Alert
Service Bulletin 777-57A0090, dated August 24, 2011, and does not need
to be included in the AD.
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 changes described previously and minor editorial
changes. We have determined that these minor changes:
<bullet> Are consistent with the intent that was proposed in the
NPRM (76 FR 77937, December 15, 2011) for correcting the unsafe
condition; and
<bullet> Do not add any additional burden upon the public than was
already proposed in the NPRM (76 FR 77937, December 15, 2011).
We also determined that these changes 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 166 airplanes of U.S. registry.
We estimate the following costs to comply with this AD:
[[Page 32891]]
Estimated Costs
----------------------------------------------------------------------------------------------------------------
Cost per Cost on U.S.
Action Labor cost Parts cost product operators
----------------------------------------------------------------------------------------------------------------
Detailed Inspection...................... 3 work-hours x $85 per hour $0 $255 $42,330
= $255.
----------------------------------------------------------------------------------------------------------------
We estimate the following costs to do any necessary replacements
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
replacements.
On-Condition Costs
----------------------------------------------------------------------------------------------------------------
Action Labor cost Parts cost Cost per product
----------------------------------------------------------------------------------------------------------------
Replace fuse pins.................... 44 work-hours x $85 per Between $15,216 and Between $18,956 and
hour = $3,740. $52,620. $56,360.
----------------------------------------------------------------------------------------------------------------
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):
2012-11-03 The Boeing Company: Amendment 39-17066; Docket No. FAA-
2011-1320; Directorate Identifier 2011-NM-208-AD.
(a) Effective Date
This AD is effective July 9, 2012.
(b) Affected ADs
None.
(c) Applicability
This AD applies to The Boeing Company Model 777-200, -200LR, -
300, -300ER, and 777F series airplanes, certificated in any
category, as identified in Boeing Alert Service Bulletin 777-
57A0090, dated August 24, 2011.
(d) Subject
Joint Aircraft System Component (JASC)/Air Transport Association
(ATA) of America Code 57, Wings.
(e) Unsafe Condition
This AD was prompted by four reports of retaining cross bolt
hardware not fully engaged into the fuse pins of the forward
trunnion lower housing of the main landing gear (MLG), which could
result in an incorrect MLG emergency landing break-away sequence. We
are issuing this AD to prevent an incorrect emergency landing MLG
break-away sequence, which could result in puncturing of the wing
box and consequent fuel leaks and an airplane fire. Failure of the
fuse pins could also result in a possible landing gear collapse
causing a runway excursion during take-off or landing.
(f) Compliance
Comply with this AD within the compliance times specified,
unless already done.
(g) Detailed Inspection and Replacement
Within 1,125 days after the effective date of this AD, perform a
detailed inspection of the fuse pin cross bolts and fuse pins of the
left and right MLG forward trunnion lower housing to verify that the
cross bolts are installed correctly and that there are no missing
fuse pins, in accordance with the Accomplishment Instructions of
Boeing Alert Service Bulletin 777-57A0090, dated August 24, 2011. If
any cross bolt of the MLG forward trunnion lower housing is not
installed correctly, or if any fuse pin of the MLG forward trunnion
lower housing is missing: Before further flight, replace all fuse
pins in the MLG forward trunnion upper and lower housing on the
side, or sides, of the airplane where the missing or incorrectly
installed fuse pin/pins were discovered, in accordance with the
Accomplishment Instructions of Boeing Alert Service Bulletin 777-
57A0090, dated August 24, 2011, except step 1 in Part 2 of paragraph
3.B of the Accomplishment Instructions of Boeing Alert Service
Bulletin 777-57A0090, dated August 24, 2011, is not considered
regulatory for the purposes of this AD.
[[Page 32892]]
(h) 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 the Related Information
section of this AD. Information may be emailed to <a href="/cdn-cgi/l/email-protection#467f6b07080b6b15232732322a236b0705096b070b09056b14233733233532350620272768212930"><span class="__cf_email__" data-cfemail="a1988ce0efec8cf2c4c0d5d5cdc48ce0e2ee8ce0eceee28cf3c4d0d4c4d2d5d2e1c7c0c08fc6ced7">[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 James Sutherland,
Aerospace Engineer, Airframe Branch, ANM-120S, FAA, Seattle Aircraft
Certification Office (ACO), 1601 Lind Avenue SW., Renton, Washington
98057-3356; phone: 425-917-6533; fax: 425-917-6590; email:
<a href="/cdn-cgi/l/email-protection#4f052e222a3c611c3a3b272a3d232e212b0f292e2e61282039"><span class="__cf_email__" data-cfemail="266c474b4355087553524e43544a4748426640474708414950">[email protected]</span></a>.
(j) Material Incorporated by Reference
(1) You must use the following service information to do the
actions required by this AD, unless the AD specifies otherwise. The
Director of the Federal Register approved the incorporation by
reference (IBR) of the following service information under 5 U.S.C.
552(a) and 1 CFR part 51:
(i) Boeing Alert Service Bulletin 777-57A0090, dated August 24,
2011.
(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; email:
<a href="/cdn-cgi/l/email-protection#9ef3fbb0fcf1fbfdf1f3defcf1fbf7f0f9b0fdf1f3"><span class="__cf_email__" data-cfemail="dab7bff4b8b5bfb9b5b79ab8b5bfb3b4bdf4b9b5b7">[email protected]</span></a>; Internet: <a href="https://www.myboeingfleet.com">https://www.myboeingfleet.com</a>.
(3) 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.
(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/cfr/ibr-locations.html">http://www.archives.gov/federal-register/cfr/ibr-locations.html</a>.
Issued in Renton, Washington, on May 18, 2012.
Michael Kaszycki,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 2012-12910 Filed 6-1-12; 8:45 am]
BILLING CODE 4910-13-P
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Retrieved: Apr 6, 2026
Rights: U.S. Government Public Domain
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