Document ID: FAA-2008-0933-0005
Agency: faa
Document Type: Rule
Title: Airworthiness Directives; Boeing Model 777 Airplanes
Posted Date: 2009-07-08T04:00Z

[Federal Register: July 8, 2009 (Volume 74, Number 129)]
[Rules and Regulations]               
[Page 32414-32417]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr08jy09-7]                         

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2008-0933; Directorate Identifier 2007-NM-261-AD; 
Amendment 39-15956; AD 2009-14-06]
RIN 2120-AA64

 
Airworthiness Directives; Boeing Model 777 Airplanes

AGENCY: Federal Aviation Administration (FAA), Department of 
Transportation (DOT).

ACTION: Final rule.

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SUMMARY: The FAA is superseding an existing airworthiness directive 
(AD), which applies to all Boeing Model 777 airplanes. That AD 
currently requires, for the drive mechanism of the horizontal 
stabilizer, repetitive detailed inspections for discrepancies, 
repetitive lubrication of the ballnut and ballscrew, repetitive 
measurements of the freeplay between the ballnut and the ballscrew, and 
corrective action if necessary. This new AD revises the compliance 
times of the existing AD. This AD results from a report of extensive 
corrosion of a ballscrew in the drive mechanism of the horizontal 
stabilizer on a Boeing Model 757 airplane, which is similar in design 
to the ballscrew on Model 777 airplanes. We are issuing this AD to 
prevent an undetected failure of the primary load path for the 
ballscrew in the drive mechanism of the horizontal stabilizer and 
subsequent wear and failure of the secondary load path, which could 
lead to loss of control of the horizontal stabilizer and consequent 
loss of control of the airplane.

DATES: This AD becomes effective August 12, 2009.
    The Director of the Federal Register approved the incorporation by 
reference of a certain publication listed in this AD as of August 12, 
2009.

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; e-mail me.boecom@boeing.com; 
Internet https://www.myboeingfleet.com.

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 AD, the regulatory evaluation, 
any comments received, and other information. The address for the 
Docket Office (telephone 800-647-5527) is the 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: Kelly McGuckin, Aerospace Engineer, 
Systems and Equipment Branch, ANM-130S, FAA, Seattle Aircraft 
Certification Office, 1601 Lind Avenue, SW., Renton, Washington 98057-
3356; telephone (425) 917-6490; fax (425) 917-6590.

SUPPLEMENTARY INFORMATION: 

Discussion

    The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 
CFR part 39 to include an AD that supersedes AD 2007-17-12, amendment 
39-15170 (72 FR 49158, August 28, 2007). The existing AD applies to all 
Boeing Model 777 airplanes. That NPRM was published in the Federal 
Register on August 29, 2008 (73 FR 50896). That NPRM proposed to retain 
the actions specified in the existing AD (i.e., for the drive mechanism 
of the horizontal stabilizer, repetitive detailed inspections for 
discrepancies, repetitive lubrication of the ballnut and ballscrew, 
repetitive measurements of the freeplay between the ballnut and the 
ballscrew, and corrective action if necessary) but with new initial 
inspection compliance times.

New Service Information

    Since issuance of the NPRM, we have reviewed Boeing Service 
Bulletin 777-27A0059, Revision 2, dated January 15, 2009. This revision 
of the service bulletin is essentially the same as Revision 1 of the 
service bulletin. (We referred to Boeing Alert Service Bulletin 777-
27A0059, Revision 1, August 18, 2005, as the appropriate source of 
service information for doing the actions proposed in the NPRM.) 
Revision 2 of the service bulletin specifies similar

[[Page 32415]]

compliance times as those proposed in the NPRM, adds clarifying 
language regarding tooling, refers to the superseded AD, and defines 
the phrase ``known serviceable condition'' for a horizontal stabilizer 
trim actuator (HSTA), including defining the term ``overhaul.''

Explanation of Removed Service Bulletin Reference Paragraph and Note 1

    We have removed the ``Service Bulletin Reference'' paragraph (i.e., 
paragraph (f) of the NPRM) and Note 1 from this AD and included 
references to Boeing Service Bulletin 777-27A0059, Revision 2, dated 
January 15, 2009, in paragraphs (g), (h), (i), and (l) of this AD. We 
have added Boeing Alert Service Bulletin 777-27A0059, Revision 1, dated 
August 18, 2005, to paragraph (j) of this AD to give credit for actions 
done before the effective date of this AD in accordance with Revision 1 
of the service bulletin.

Comments

    We provided the public the opportunity to participate in the 
development of this AD. We have considered the comments that have been 
received on the NPRM.

Requests for Clarification of ``Overhaul'' and ``Serviceable''

    The Air Transport Association, on behalf of one of its members, 
American Airlines, requests that we clarify the meaning of ``overhaul'' 
and ``serviceable'' in both the NPRM and Boeing Alert Service Bulletin 
777-27A0059, Revision 1, August 18, 2005.
    American Airlines states that the NPRM specifies to replace an HSTA 
with a new or ``serviceable'' unit in accordance with Boeing Alert 
Service Bulletin 777-27A0059, Revision 1, dated August 18, 2005, and 
that the NPRM also states that no person shall install, on any 
airplane, an HSTA that is not new or ``overhauled,'' unless a detailed 
inspection, freeplay measurement, and lubrication of that actuator have 
been performed in accordance with paragraphs (h), (i), and (j) of the 
proposed AD (i.e., paragraphs (g), (h), and (i) of this final rule). In 
addition, American Airlines states that the component maintenance 
manual (CMM) for the subject HSTA does not have a defined ``overhaul'' 
work scope. American Airlines believes that the NPRM and the service 
bulletin should provide the specific procedures and/or CMM requirements 
for what constitutes an ``overhauled'' and/or ``serviceable'' HSTA.
    We agree with the commenters. Note 6 of paragraph 3.A. of Boeing 
Service Bulletin 777-27A0059, Revision 2, dated January 15, 2009, now 
defines the phrase ``known serviceable condition'' for an HSTA, 
including defining the term ``overhaul.'' We have added the phrase 
``known serviceable condition'' to paragraphs (f)(2) through (f)(4), 
(g), and (h) of this AD in place of the words ``serviceable HSTA'' and 
``new or overhauled'' in the NPRM to be in line with the usage in that 
service bulletin. We have also changed paragraph (l) of this AD to 
refer to the definition of ``known serviceable condition'' in that 
service bulletin. In addition, new Note 1 referring to ``known 
serviceable condition'' has been added to the final rule.

Conclusion

    We have carefully reviewed the available data, including the 
comments that have been received, and determined that air safety and 
the public interest require adopting the AD with the changes described 
previously. We have determined that these changes will neither increase 
the economic burden on any operator nor increase the scope of the AD.

Costs of Compliance

    There are about 596 airplanes of the affected design in the 
worldwide fleet. This AD affects about 203 airplanes of U.S. registry. 
The new requirements of this AD add no additional economic burden. The 
current costs of the existing AD are repeated for the convenience of 
affected operators, as follows.
    The maintenance records check takes about 1 work hour per airplane, 
at an average labor rate of $80 per work hour. Based on these figures, 
the estimated cost of the maintenance records check for U.S. operators 
is $16,240, or $80 per airplane.
    The detailed inspection takes about 1 work hour per airplane, at an 
average labor rate of $80 per work hour. Based on these figures, the 
estimated cost of the inspection for U.S. operators is $16,240, or $80 
per airplane, per inspection cycle.
    The freeplay measurement takes about 5 work hours per airplane, at 
an average labor rate of $80 per work hour. Based on these figures, the 
estimated cost of the freeplay measurement for U.S. operators is 
$81,200, or $400 per airplane, per measurement cycle.
    The required lubrication takes about 1 work hour per airplane, at 
an average labor rate of $80 per work hour. Based on these figures, the 
estimated cost of the lubrication for U.S. operators is $16,240, or $80 
per airplane, per lubrication cycle.

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 have determined that 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); 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.
    We prepared a regulatory evaluation of the estimated costs to 
comply with this AD and placed it in the AD docket. See the ADDRESSES 
section for a location to examine the regulatory evaluation.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, Safety.

Adoption of the Amendment

0
Accordingly, under the authority delegated to me by the Administrator, 
the FAA amends 14 CFR part 39 as follows:

[[Page 32416]]

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 Federal Aviation Administration (FAA) amends Sec.  39.13 by 
removing amendment 39-15170 (72 FR 49158, August 28, 2007) and by 
adding the following new airworthiness directive (AD):

2009-14-06 Boeing: Amendment 39-15956. Docket No. FAA-2008-0933; 
Directorate Identifier 2007-NM-261-AD.

Effective Date

    (a) This AD becomes effective August 12, 2009.

Affected ADs

    (b) This AD supersedes AD 2007-17-12.

Applicability

    (c) This AD applies to all Boeing Model 777 airplanes, 
certificated in any category.

Unsafe Condition

    (d) This AD results from a report of extensive corrosion of a 
ballscrew in the drive mechanism of the horizontal stabilizer on a 
Boeing Model 757 airplane, which is similar in design to the 
ballscrew on Model 777 airplanes. We are issuing this AD to prevent 
an undetected failure of the primary load path for the ballscrew in 
the drive mechanism of the horizontal stabilizer and subsequent wear 
and failure of the secondary load path, which could lead to loss of 
control of the horizontal stabilizer and consequent loss of control 
of the airplane.

Compliance

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

Restatement of Requirements of AD 2007-17-12 With Revised Compliance 
Times and Updated Service Information

Maintenance Records Check

    (f) For airplanes that have received an original airworthiness 
certificate or original export certificate of airworthiness prior to 
the effective date of this AD: Within 180 days or 3,500 flight hours 
after the effective date of this AD, whichever occurs first, perform 
a maintenance records check or inspect to determine the status of 
the horizontal stabilizer trim actuator (HSTA) as specified in 
paragraph (f)(1), (f)(2), (f)(3), or (f)(4) of this AD, as 
applicable:
    (1) The original HSTA delivered with the airplane has not been 
removed and is still installed on the airplane;
    (2) The original HSTA has been replaced with an HSTA in a known 
serviceable condition;
    (3) The original HSTA has been replaced with an HSTA that is not 
in a known serviceable condition, and which has not received a 
detailed inspection and freeplay measurement as described in 
paragraphs (g) and (h) of this AD since that replacement; or
    (4) The original HSTA has been replaced with an HSTA that is not 
in a known serviceable condition, and which has received a detailed 
inspection and freeplay measurement as described in paragraphs (g) 
and (h) of this AD since that replacement.

    Note 1:  The phrase ``known serviceable condition'' is defined 
in section 3.A., Note 6, of Boeing Service Bulletin 777-27A0059, 
Revision 2, dated January 15, 2009.

Detailed Inspection

    (g) Within the compliance times specified in paragraphs (g)(1), 
(g)(2), (g)(3), and (g)(4) of this AD, as applicable: Perform a 
detailed inspection for discrepancies of the horizontal stabilizer 
trim actuator ballnut and ballscrew, in accordance with Part 1 of 
the Accomplishment Instructions of Boeing Service Bulletin 777-
27A0059, Revision 2, dated January 15, 2009. Repeat the detailed 
inspection thereafter at intervals not to exceed 3,500 flight hours 
or 12 months, whichever occurs first. If any discrepancy is found 
during any inspection required by this AD, before further flight, 
replace the actuator with an actuator in a known serviceable 
condition, in accordance with the Accomplishment Instructions of 
Boeing Service Bulletin 777-27A0059, Revision 2, dated January 15, 
2009.
    (1) For airplanes identified in paragraph (f)(1) of this AD: 
Before the accumulation of 15,000 total flight hours, or within 18 
months after the effective date of this AD, whichever occurs later.
    (2) For airplanes identified in paragraph (f)(2) or (f)(4) of 
this AD: Before the accumulation of 15,000 flight hours since the 
replacement of the HSTA, or within 18 months after the effective 
date of this AD, whichever occurs later.
    (3) For airplanes identified in paragraph (f)(3) of this AD: 
Before the accumulation of 3,500 flight hours since the replacement 
of the HSTA, or within 12 months after the effective date of this 
AD, whichever occurs later.
    (4) For airplanes that have received an original airworthiness 
certificate or original export certificate of airworthiness on or 
after the effective date of this AD: Before the accumulation of 
15,000 total flight hours, or within 18 months after the issuance of 
the original airworthiness certificate or original export 
certificate of airworthiness, whichever occurs later.

Freeplay Measurement (Inspection)

    (h) Within the compliance times specified in paragraphs (h)(1), 
(h)(2), (h)(3), and (h)(4) of this AD, as applicable: Perform a 
freeplay measurement of the ballnut and ballscrew in accordance with 
Part 2 of the Accomplishment Instructions of Boeing Service Bulletin 
777-27A0059, Revision 2, dated January 15, 2009. Repeat the freeplay 
measurement thereafter at intervals not to exceed 18,000 flight 
hours or 60 months, whichever occurs first. If the freeplay is found 
to exceed the limits specified in the service bulletin during any 
measurement required by this AD, before further flight, replace the 
actuator with an actuator in a known serviceable condition, in 
accordance with the Accomplishment Instructions of Boeing Service 
Bulletin 777-27A0059, Revision 2, dated January 15, 2009.
    (1) For airplanes identified in paragraph (f)(1) of this AD: 
Before the accumulation of 15,000 total flight hours, or within 18 
months after the effective date of this AD, whichever occurs later.
    (2) For airplanes identified in paragraph (f)(2) or (f)(4) of 
this AD: Before the accumulation of 15,000 flight hours since the 
replacement of the HSTA, or within 18 months after the effective 
date of this AD, whichever occurs later.
    (3) For airplanes identified in paragraph (f)(3) of this AD: 
Before the accumulation of 3,500 flight hours since the replacement 
of the HSTA, or within 12 months after the effective date of this 
AD, whichever occurs later.
    (4) For airplanes that have received an original airworthiness 
certificate or original export certificate of airworthiness on or 
after the effective date of this AD: Before the accumulation of 
15,000 total flight hours, or within 18 months after the issuance of 
the original airworthiness certificate or original export 
certificate of airworthiness, whichever occurs later.

Lubrication

    (i) Within the compliance times specified in paragraphs (i)(1), 
(i)(2), (i)(3), and (i)(4) of this AD, as applicable: Lubricate the 
ballnut and ballscrew in accordance with Part 3 of the 
Accomplishment Instructions of Boeing Service Bulletin 777-27A0059, 
Revision 2, dated January 15, 2009. Repeat the lubrication 
thereafter at intervals not to exceed 2,000 flight hours or 12 
months, whichever occurs first.
    (1) For airplanes identified in paragraph (f)(1) of this AD: 
Before the accumulation of 15,000 total flight hours, or within 18 
months after the effective date of this AD, whichever occurs later.
    (2) For airplanes identified in paragraph (f)(2) or (f)(4) of 
this AD: Before the accumulation of 15,000 flight hours since the 
replacement of the HSTA, or within 18 months after the effective 
date of this AD, whichever occurs later.
    (3) For airplanes identified in paragraph (f)(3) of this AD: 
Before the accumulation of 3,500 flight hours since the replacement 
of the HSTA, or within 12 months after the effective date of this 
AD, whichever occurs later.
    (4) For airplanes that have received an original airworthiness 
certificate or original export certificate of airworthiness on or 
after the effective date of this AD: Before the accumulation of 
15,000 total flight hours, or within 18 months after the issuance of 
the original airworthiness certificate or original export 
certificate of airworthiness, whichever occurs later.

Credit for Actions Accomplished According to Earlier Issues of the 
Service Bulletin

    (j) Actions performed prior to the effective date of this AD, in 
accordance with Boeing Alert Service Bulletin 777-27A0059, dated 
September 18, 2003; or Boeing Alert Service

[[Page 32417]]

Bulletin 777-27A0059, Revision 1, dated August 18, 2005; are 
considered acceptable for compliance with the corresponding actions 
specified in paragraphs (g), (h), and (i) of this AD.

Credit for Hard-Time Replacement of HSTA

    (k) Any HSTA overhauled within the compliance times specified in 
paragraphs (g), (h), and (i) of this AD or before the effective date 
of this AD--as part of a ``hard-time'' replacement program that 
includes removal of the HSTA from the airplane and overhaul of the 
stabilizer ballscrew in accordance with original equipment 
manufacturer component maintenance manual instructions--meets the 
intent of one detailed inspection, one freeplay inspection, and one 
lubrication of the HSTA. Therefore, any such HSTA is considered 
acceptable for compliance with the initial accomplishment of the 
actions specified in paragraphs (g), (h), and (i) of this AD, and 
repetitions of those actions may be determined from the performance 
date of that overhaul.

Parts Installation

    (l) As of the effective date of this AD, no person may install, 
on any airplane, a horizontal stabilizer trim actuator that is not 
in a ``known serviceable condition'' as defined in Note 6, section 
3.A., of Boeing Alert Service Bulletin 777-27A0059, Revision 2, 
dated January 15, 2009; unless a detailed inspection, freeplay 
measurement, and lubrication of that actuator are performed in 
accordance with paragraphs (g), (h), and (i) of this AD, as 
applicable.

Alternative Methods of Compliance (AMOCs)

    (m)(1) The Manager, Seattle Aircraft Certification Office (ACO), 
FAA, ATTN: Kelly McGuckin, Aerospace Engineer, Systems and Equipment 
Branch, ANM-130S, FAA, Seattle ACO, 1601 Lind Avenue, SW., Renton, 
Washington 98057-3356; telephone (425) 917-6490; fax (425) 917-6590; 
has the authority to approve AMOCs for this AD, if requested using 
the procedures found in 14 CFR 39.19.
    (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 appropriate principal inspector (PI) in the FAA 
Flight Standards District Office (FSDO), or lacking a PI, your local 
FSDO.

Material Incorporated by Reference

    (n) You must use Boeing Service Bulletin 777-27A0059, Revision 
2, dated January 15, 2009, to do the actions required by this AD, 
unless the AD specifies otherwise.
    (1) The Director of the Federal Register approved the 
incorporation by reference of this service information under 5 
U.S.C. 552(a) and 1 CFR part 51.
    (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; telephone 
206-544-5000, extension 1, fax 206-766-5680; e-mail 
me.boecom@boeing.com; Internet https://www.myboeingfleet.com.
    (3) You may review copies of the 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 or 425-227-1152.
    (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: http://
www.archives.gov/federal_ register/code_of_federal_regulations/
ibr_locations.html.

    Issued in Renton, WA, on June 24, 2009.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. E9-15639 Filed 7-7-09; 8:45 am]

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