[Federal Register Volume 72, Number 166 (Tuesday, August 28, 2007)]
[Rules and Regulations]
[Pages 49158-49161]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: E7-16419]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2006-24270; Directorate Identifier 2005-NM-200-AD; 
Amendment 39-15170; AD 2007-17-12]
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 adopting a new airworthiness directive (AD) for all 
Boeing Model 777 series airplanes. This AD 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 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

[[Page 49159]]

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 October 2, 2007.
    The Director of the Federal Register approved the incorporation by 
reference of a certain publication listed in the AD as of October 2, 
2007.

ADDRESSES: You may examine the AD docket on the Internet at http://dms.dot.gov or in person at the U.S. Department of Transportation, 
Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 
New Jersey Avenue, SE., Washington, DC.
    Contact Boeing Commercial Airplanes, P.O. Box 3707, Seattle, 
Washington 98124-2207, for service information identified in this AD.

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: 

Examining the Docket

    You may examine the AD docket on the Internet at http://dms.dot.gov 
or in person at the Docket Operations office between 9 a.m. and 5 p.m., 
Monday through Friday, except Federal holidays. The Docket Operations 
office (telephone (800) 647-5527) is located on the ground floor of the 
West Building at the DOT street address stated in the ADDRESSES 
section.

Discussion

    The FAA issued a supplemental notice of proposed rulemaking (NPRM) 
to amend 14 CFR part 39 to include an AD that would apply to all Boeing 
Model 777 airplanes. That supplemental NPRM was published in the 
Federal Register on June 18, 2007 (72 FR 33411). That supplemental NPRM 
proposed to require, 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. That supplemental NPRM also proposed to 
add airplanes to the applicability of the proposed AD.

Comments

    We provided the public the opportunity to participate in the 
development of this AD. We have considered the comment received. The 
commenter, Boeing, supports the supplemental NPRM.

Clarification of Alternative Method of Compliance (AMOC) Paragraph

    We have revised this action to clarify the appropriate procedure 
for notifying the principal inspector before using any approved AMOC on 
any airplane to which the AMOC applies.

Conclusion

    We have carefully reviewed the available data, including the 
comment received, and determined that air safety and the public 
interest require adopting the AD with the change described previously. 
We have determined that this change 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 required 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 required 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 required 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:

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 
adding the following new airworthiness directive (AD):


[[Page 49160]]


2007-17-12 Boeing: Amendment 39-15170. Docket No. FAA-2006-24270; 
Directorate Identifier 2005-NM-200-AD.

Effective Date

    (a) This AD becomes effective October 2, 2007.

Affected ADs

    (b) None.

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.

Service Bulletin Reference

    (f) The term ``service bulletin,'' as used in this AD, means 
Boeing Alert Service Bulletin 777-27A0059, Revision 1, dated August 
18, 2005.

    Note 1: The service bulletin refers to the Boeing 777 Aircraft 
Maintenance Manual (AMM), Subjects 12-21-05, 27-41-13, and 29-11-00, 
as additional sources of service information for accomplishing the 
actions required by this AD.

Maintenance Records Check

    (g) For airplanes that have received a 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 whether any horizontal stabilizer trim actuator 
has been replaced for any issue described in the service bulletin 
with a serviceable actuator that was not new or overhauled, and has 
not received a detailed inspection and freeplay measurement since 
the replacement.

Detailed Inspection

    (h) Within the compliance times specified in paragraph (h)(1) or 
(h)(2) 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 the service bulletin. 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 a new or serviceable actuator in accordance with 
the Accomplishment Instructions of the service bulletin.
    (1) For airplanes identified in paragraph (g) of this AD on 
which the actuator has not been replaced: 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 (g) of this AD on 
which the actuator has been replaced, and for airplanes having 
received a certificate of airworthiness after the effective date of 
this AD: Before the accumulation of 3,500 flight hours or within 24 
months after the effective date of this AD, whichever occurs later.

Freeplay Measurement (Inspection)

    (i) Within the compliance times specified in paragraph (i)(1) or 
(i)(2) of this AD, as applicable: Perform a freeplay measurement of 
the ballnut and ballscrew in accordance with Part 2 of the 
Accomplishment Instructions of the service bulletin. 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 a new or serviceable actuator in 
accordance with the Accomplishment Instructions of the service 
bulletin.
    (1) For airplanes identified in paragraph (g) of this AD on 
which the actuator has not been replaced: 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 (g) of this AD on 
which the actuator has been replaced, and for airplanes having 
received a certificate of airworthiness after the effective date of 
this AD: Before the accumulation of 3,500 flight hours or within 24 
months after the effective date of this AD, whichever occurs later.

Lubrication

    (j) Within the compliance times specified in paragraph (j)(1) or 
(j)(2) of this AD, as applicable: Lubricate the ballnut and 
ballscrew in accordance with Part 3 of the Accomplishment 
Instructions of the service bulletin. 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 (g) of this AD on 
which the actuator has not been replaced: 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 (g) of this AD on 
which the actuator has been replaced, and for airplanes having 
received a certificate of airworthiness after the effective date of 
this AD: Before the accumulation of 3,500 flight hours or within 24 
months after the effective date of this AD, whichever occurs later.

Credit for Using Original Issue of Service Bulletin

    (k) Actions performed prior to the effective date of this AD in 
accordance with Boeing Alert Service Bulletin 777-27A0059, dated 
September 18, 2003, are considered acceptable for compliance with 
the corresponding actions of this AD.

Credit for Hard-Time Replacement of Actuator

    (l) Any actuator overhauled within the compliance times 
specified in paragraphs (h), (i), and (j) of this AD or before the 
effective date of this AD--as part of a ``hard-time'' replacement 
program that includes removal of the stabilizer actuator 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 stabilizer 
ballscrew. Therefore, any such actuator is considered acceptable for 
compliance with the initial accomplishment of the actions specified 
in paragraphs (h), (i), and (j) of this AD, and repetitions of those 
actions may be determined from the performance date of that 
overhaul.

Parts Installation

    (m) As of the effective date of this AD, no person may install, 
on any airplane, a horizontal stabilizer trim actuator 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 this AD, as 
applicable.

Alternative Methods of Compliance (AMOCs)

    (n)(1) The Manager, Seattle Aircraft Certification Office, FAA, 
has the authority to approve AMOCs for this AD, if requested in 
accordance with 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

    (o) You must use Boeing Alert Service Bulletin 777-27A0059, 
Revision 1, dated August 18, 2005, to perform the actions that are 
required by this AD, unless the AD specifies otherwise. The Director 
of the Federal Register approved the incorporation by reference of 
this document in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. 
Contact Boeing Commercial Airplanes, P.O. Box 3707, Seattle, 
Washington 98124-2207, for a copy of this service information. You 
may review copies at the FAA, Transport Airplane Directorate, 1601 
Lind Avenue SW., Renton, Washington; or at the National Archives and 
Records Administration (NARA). For information on the availability 
of this material at NARA, call 202-741-6030,

[[Page 49161]]

or go to: http://www.archives.gov/federal-register/cfr/ibr-locations.html.

    Issued in Renton, Washington, on August 14, 2007.
Stephen P. Boyd,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
 [FR Doc. E7-16419 Filed 8-27-07; 8:45 am]
BILLING CODE 4910-13-P