
[Federal Register: December 1, 2010 (Volume 75, Number 230)]
[Proposed Rules]               
[Page 74668-74670]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr01de10-25]                         

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2010-1156; Directorate Identifier 2010-NM-128-AD]
RIN 2120-AA64

 
Airworthiness Directives; The Boeing Company Model 777-200, -
200LR, -300, and -300ER Series 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 
certain Model 777-200, -200LR, -300, and -300ER series airplanes. This 
proposed AD would require repetitive detailed inspections for 
disbonding and tearing and measurements for wear of the internal 
diameter (ID) of the Karon-lined bushings of the bulkhead support 
jackscrew fitting and of the jackscrew fitting of the horizontal 
stabilizer; repetitive installations of the horizontal stabilizer trim 
actuator (HSTA); and if necessary, replacement of the bushings with new 
bushings and all applicable related investigative and corrective 
actions. This proposed AD results from a report indicating that a 
Karon-lined bushing with the liner broken into five pieces was found 
during a scheduled inspection of the HSTA components; the broken liner 
had worn and disbonded from the bushing. We are proposing this AD to 
detect and correct discrepancies of the HSTA attachment locations, 
which could result in reduced structural integrity of the horizontal 
stabilizer and consequent loss of controllability of the airplane.

DATES: We must receive comments on this proposed AD by January 18, 
2011.

ADDRESSES: You may send comments 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: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue, SE., Washington, DC 20590, 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; telephone 206-
544-5000, extension 1, fax 206-766-5680; e-mail 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 (telephone 800-647-5527) is in the 
ADDRESSES section. Comments will be available in the AD docket shortly 
after receipt.

FOR FURTHER INFORMATION CONTACT: Duong Tran, Aerospace Engineer, 
Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office, 
1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone (425) 
917-6452; fax (425) 917-6590.

SUPPLEMENTARY INFORMATION:

Comments Invited

    We invite you to send any written relevant data, views, or 
arguments about this proposed AD. Send your comments to an address 
listed under the ADDRESSES section. Include ``Docket No. FAA-2010-1156; 
Directorate Identifier 2010-NM-128-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.

[[Page 74669]]

Discussion

    We received a report indicating that a Karon-lined bushing with the 
liner broken into five pieces was found during a scheduled inspection 
of the horizontal stabilizer trim actuator (HSTA) components; the 
broken liner had worn and disbonded from the bushing. The broken liner 
was found on a 777-200 airplane that had accumulated 35,145 total 
flight hours and 5,335 total flight cycles. Analysis by the 
manufacturer revealed that the broken liner was one of 149 bushings on 
which an early manufacturing process was used; that process has since 
been improved. Further investigation and analysis by the manufacturer 
shows that Karon-lined bushings in the HSTA and HSTA attachment 
locations on the airplane structure using both the early and the 
improved process are susceptible to wear in service. The analysis also 
shows that the wear may cause excessive joint clearance which could 
lead to fatigue cracking of the pins. This condition, if not corrected, 
could result in reduced structural integrity of the horizontal 
stabilizer and consequent loss of controllability of the airplane.

Relevant Service Information

    We have reviewed Boeing Alert Service Bulletin 777-55A0017, dated 
May 20, 2010, which describes procedures for:
     Repetitive detailed inspections for disbonding and tearing 
and measurements for wear of the internal diameter (ID) of the Karon-
lined bushings of the bulkhead support jackscrew fitting; and 
replacement of the bushings with new bushings if necessary: The 
replacement includes related investigative and corrective actions, if 
necessary. The related investigative actions include a surface high-
frequency eddy current inspection for cracking of the inner surface of 
the hole, and measurement of the ID, of the intermediate sleeve. The 
corrective action for cracking of the intermediate sleeve or 
measurements outside the ID specified in the service bulletin is 
replacement of the intermediate sleeve, including related investigative 
and corrective actions if necessary. The related investigative actions 
include a surface high-frequency eddy current inspection for cracking 
of the inner surface of the hole, and measurement of the ID of the hole 
of the bulkhead support jackscrew fitting. The corrective action for 
cracking of the bulkhead support jackscrew fitting or measurements 
outside the ID specified in the service bulletin is contacting Boeing.
     Repetitive detailed inspections for disbonding and tearing 
and measurements for wear of the internal diameter (ID) of the Karon-
lined bushings of the jackscrew fitting of the horizontal stabilizer; 
and replacement of the bushings with new bushings if necessary.
     Repetitively installing either a known serviceable or 
overhauled HSTA.

FAA's Determination and Requirements of This Proposed AD

    We are proposing this AD because we evaluated all relevant 
information and determined the unsafe condition described previously is 
likely to exist or develop in other products of the same type design. 
This proposed AD would require accomplishing the actions specified in 
the service information described previously, except as discussed under 
``Difference Between the Proposed AD and Service Information.''

Difference Between the Proposed AD and Service Information

    The service bulletin specifies to contact the manufacturer for 
instructions on how to repair certain conditions, but this proposed AD 
would require repairing those conditions in one of the following ways:
     Using a method that we approve; or
     Using data that meet the certification basis of the 
airplane, and that have been approved by an Authorized Representative 
for the Boeing Commercial Airplanes Organization Designation 
Authorization whom we have authorized to make those findings.

Costs of Compliance

    We estimate that this proposed AD would affect 145 airplanes of 
U.S. registry. We also estimate that it would take about 7 work-hours 
per product to comply with the detailed inspection, measurement, and 
installation in this proposed AD. The average labor rate is $85 per 
work-hour. Based on these figures, we estimate the cost of this 
proposed AD to the U.S. operators to be $86,275, or $595 per product.

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), and
    3. 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.
    You can find our regulatory evaluation and the estimated costs of 
compliance in the AD Docket.

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 AD:

The Boeing Company: Docket No. FAA-2010-1156; Directorate Identifier 
2010-NM-128-AD.

[[Page 74670]]

Comments Due Date

    (a) We must receive comments by January 18, 2011.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to The Boeing Company Model 777-200, -200LR, 
-300, and -300ER series airplanes, certificated in any category, as 
identified in Boeing Alert Service Bulletin 777-55A0017, dated May 
20, 2010.

Subject

    (d) Air Transport Association (ATA) of America Code 55: 
Stabilizers.

Unsafe Condition

    (e) This AD results from a report indicating that a Karon-lined 
bushing with the liner broken into five pieces was found during a 
scheduled inspection of the horizontal stabilizer trim actuator 
(HSTA) components; the broken liner had worn and disbonded from the 
bushing. The Federal Aviation Administration is issuing this AD to 
detect and correct discrepancies of the HSTA attachment locations, 
which could result in reduced structural integrity of the horizontal 
stabilizer and consequent loss of controllability of the airplane.

Compliance

    (f) You are responsible for having the actions required by this 
AD performed within the compliance times specified, unless the 
actions have already been done.

Inspection/Related Investigative and Corrective Actions

    (g) Before the accumulation of 32,000 total flight cycles, or 
within 24 months after the effective date of this AD, whichever 
occurs later: Do a detailed inspection for disbonding and tearing, 
and a measurement for wear of the internal diameter (ID) of the 
Karon-lined bushings of the bulkhead support jackscrew fitting and 
of the jackscrew fitting of the horizontal stabilizer; replace 
bushings with new bushings, as applicable; do all applicable related 
investigative and corrective actions; and install either a known 
serviceable or overhauled HSTA. Do the actions in accordance with 
the Accomplishment Instructions of Boeing Alert Service Bulletin 
777-55A0017, dated May 20, 2010, except as provided by paragraph (h) 
of this AD. Do all applicable related investigative and corrective 
actions before further flight. Repeat the actions required by this 
paragraph thereafter at intervals not to exceed 16,000 flight 
cycles.

Exceptions to Corrective Actions

    (h) If, during any inspection or measurement required by this 
AD, any damage is found, or the inner diameter is greater than the 
allowable hole diameter, and Part 1, Step 3.B.2.a.(1)(a)1)a) of the 
Accomplishment Instructions of Boeing Alert Service Bulletin 777-
55A0017, dated May 20, 2010, specifies to contact Boeing for 
appropriate action: Before further flight, do the repair using a 
method approved in accordance with the procedures specified in 
paragraph (i) of 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. Send information to 
ATTN: Duong Tran, Aerospace Engineer, Airframe Branch, ANM-120S, 
FAA, Seattle ACO, 1601 Lind Avenue, SW., Renton, Washington 98057-
3356; telephone (425) 917-6452; fax (425) 917-6590. Or information 
may be e-mailed to: 9-ANM-Seattle-ACO-AMOC-Requests@faa.gov.
    (2) To request a different method of compliance or a different 
compliance time for this AD, follow the procedures in 14 CFR 39.19. 
Before using any approved AMOC on any airplane to which the AMOC 
applies, notify your principal maintenance inspector (PMI) or 
principal avionics inspector (PAI), as appropriate, or lacking a 
principal inspector, your local Flight Standards District Office. 
The AMOC approval letter must specifically reference this AD.
    (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.

    Issued in Renton, Washington, on November 15, 2010.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2010-30138 Filed 11-30-10; 8:45 am]
BILLING CODE 4910-13-P

