
[Federal Register Volume 76, Number 241 (Thursday, December 15, 2011)]
[Proposed Rules]
[Pages 77937-77939]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2011-32077]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2011-1320; Directorate Identifier 2011-NM-208-AD]
RIN 2120-AA64


Airworthiness Directives; The Boeing Company Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: We propose to adopt a new airworthiness directive (AD) for all 
The Boeing Company Model 777 airplanes. This proposed 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 proposed AD would require 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 proposing 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 
premature landing gear collapse causing a runway excursion during take-
off or landing.

DATES: We must receive comments on this proposed AD by January 30, 
2012.

ADDRESSES: You may send comments, using the procedures found in 14 CFR 
11.43 and 11.45, 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: Deliver to Mail address above 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; phone: (206) 
544-5000, extension 1; fax: (206) 766-5680; email: 
me.boecom@boeing.com; 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 (phone: (800) 647-5527) is in the 
ADDRESSES section. Comments will be available in the AD docket shortly 
after receipt.

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: James.Sutherland@faa.gov.

SUPPLEMENTARY INFORMATION: 

Comments Invited

    We invite you to send any written relevant data, views, or 
arguments about this proposal. Send your comments to an address listed 
under the ADDRESSES section. Include ``Docket No. FAA-2011-1320; 
Directorate Identifier 2011-NM-208-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 four reports of retaining cross bolt hardware not 
fully engaged into the fuse pins of the MLG forward trunnion lower 
housing. Reports indicated the incorrectly installed cross bolts were 
found during a scheduled C-check inspection, an MLG replacement, a 4C 
inspection, and a hard landing inspection. All findings indicated that 
the cross bolt and lock wire were intact, but the cross bolt had not 
properly engaged in the fuse pin. The cross bolt and lock wire are used 
to prevent the fuse pin from migrating out of position. A migrated or 
missing fuse pin in the MLG forward trunnion lower housing can cause 
the remaining fuse pins in the MLG forward trunnion upper and lower 
housing to wear at a faster rate and also result in possible failure of 
the adjacent fuse pins in the MLG forward trunnion upper and lower 
housing. Failure of the fuse pins in the MLG forward trunnion upper and 
lower housing could result in an incorrect emergency landing MLG break-
away sequence, which will cause the MLG to puncture the wing box and 
consequent fuel leaks and possible airplane fire. Failure of the fuse 
pins could also result in a premature landing gear collapse causing a 
runway excursion during take-off or landing.

Relevant Service Information

    We reviewed Boeing Alert Service Bulletin 777-57A0090, dated August 
24, 2011. This service information describes procedures for doing 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

[[Page 77938]]

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.

FAA's Determination

    We are proposing this AD because we evaluated all the relevant 
information and determined the unsafe condition described previously is 
likely to exist or develop in other products of the same type design.

Proposed AD Requirements

    This proposed AD would require accomplishing the actions specified 
in the service information described previously.

Costs of Compliance

    We estimate that this proposed AD will affect 166 airplanes of U.S. 
registry.
    We estimate the following costs to comply with this proposed AD:

                                                 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 proposed 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 proposed 
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

    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),
    (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.

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 
airworthiness directive (AD):

The Boeing Company: Docket No. FAA-2011-1320; Directorate Identifier 
2011-NM-208-AD.

(a) Comments Due Date

    We must receive comments by January 30, 2012.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to all The Boeing Company Model 777-200, -200LR, 
-300, -300ER, and 777F series airplanes; certificated in any 
category.

(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 premature 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

[[Page 77939]]

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, in accordance with 
the Accomplishment Instructions of Boeing Alert Service Bulletin 
777-57A0090, dated August 24, 2011.

    Note 1:  The service bulletin accomplishment instructions might 
refer to other procedures. When the words ``refer to'' are used and 
the operator has an accepted alternative procedure, the accepted 
alternative procedure can be used to comply with the AD. When the 
words ``in accordance with'' are included in the instruction, the 
procedure in the design approval holder (DAH) document must be used 
to comply with the AD.

 (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 9-ANM-Seattle-ACO-AMOC-Requests@faa.gov.
    (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

    (1) 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: James.Sutherland@faa.gov.
    (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: 
me.boecom@boeing.com; 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.

    Issued in Renton, Washington, on December 6, 2011.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2011-32077 Filed 12-14-11; 8:45 am]
BILLING CODE 4910-13-P


