[Federal Register Volume 70, Number 192 (Wednesday, October 5, 2005)]
[Rules and Regulations]
[Pages 58005-58007]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 05-19871]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2005-21138; Directorate Identifier 2004-NM-131-AD; 
Amendment 39-14310; AD 2005-20-16]
RIN 2120-AA64


Airworthiness Directives; Boeing Model 737-100, -200, and -200C 
Series 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 
certain Boeing Model 737-100, -200, and -200C series airplanes. This AD 
requires a one-time detailed inspection for cracking of the lugs of the 
inboard attach fittings of the wing leading edge slat tracks at slat 
numbers 2 and 5; prior or concurrent actions for certain airplanes; 
repetitive high-frequency eddy current (HFEC) inspections for cracking 
of the lug surfaces of those inboard attach fittings if necessary; and 
replacement of the attach fittings with new, improved fittings. This AD 
results from reports of damage to the lugs of certain inboard attach 
fittings of the leading edge slat tracks. We are issuing this AD to 
prevent a lifted slat, which, if the airplane performs any non-normal 
maneuver during takeoff or landing at very high angles of attack, could 
lead to the loss of the slat and reduced control of the airplane.

DATES: This AD becomes effective November 9, 2005.
    The Director of the Federal Register approved the incorporation by 
reference of certain publications listed in the AD as of November 9, 
2005.

ADDRESSES: You may examine the AD docket on the Internet at http://dms.dot.gov or in person at the Docket Management Facility, U.S. 
Department of Transportation, 400 Seventh Street SW., Nassif Building, 
Room PL-401, 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: Nancy Marsh, Aerospace Engineer, 
Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office, 
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 
917-6440; fax (425) 917-6590.

SUPPLEMENTARY INFORMATION:

Examining the Docket

    You may examine the airworthiness directive (AD) docket on the 
Internet at http://dms.dot.gov or in person at the Docket Management 
Facility office between 9 a.m. and 5 p.m., Monday through Friday, 
except Federal holidays. The Docket Management Facility office 
(telephone (800) 647-5227) is located on the plaza level of the Nassif 
Building at the street address stated in the ADDRESSES section.

Discussion

    The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 
CFR part 39 to include an AD that would apply to certain Boeing Model 
737-100, -200, and -200C series airplanes. That NPRM was published in 
the Federal Register on May 9, 2005 (70 FR 24335). That NPRM proposed 
to require a one-time detailed inspection for cracking of the lugs of 
the inboard attach fittings of the wing leading edge slat tracks at 
slat numbers 2 and 5; prior or concurrent actions for certain 
airplanes; repetitive high-frequency eddy current (HFEC) inspections 
for cracking of the lug surfaces of those inboard attach fittings if 
necessary; and replacement of the attach fittings with new, improved 
fittings.

Comments

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

Support for the NPRM

    One commenter, the manufacturer, concurs with the content of the 
NPRM.

Request To Disallow Use of Aluminum Attach Fittings

    One commenter requests that we revise the NPRM to prohibit 
replacing aluminum attach fittings with new aluminum fittings after the 
effective date of the AD. The commenter provides no justification for 
this request.
    We do not agree with this request. The manufacturer recommends 
that, unless cracked, an aluminum attach fitting need not be replaced 
until 120 months or 30,000 flight cycles, whichever comes first, after 
the effective date of the AD. We have determined that the manufacturer 
recommendation is sound and that the repetitive inspections of the 
aluminum fittings required by the AD are sufficient to maintain safety 
until the aluminum fittings are removed from service. We have not 
changed the AD in this regard.

Explanation of Change Made to This AD

    We have revised the ``Alternative Methods of Compliance (AMOCs)'' 
paragraph in this AD to clarify the delegation authority for Authorized 
Representatives for the Boeing Commercial Airplanes Delegation Option 
Authorization.

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 
comments that have been submitted, and determined that air safety and 
the public interest require adopting the AD with the changes described 
previously. We have determined that these changes

[[Page 58006]]

will neither increase the economic burden on any operator nor increase 
the scope of the AD.

Costs of Compliance

    This AD will affect about 909 airplanes worldwide. The following 
table provides the estimated costs for U.S. operators to comply with 
this AD.

                                                                     Estimated Costs
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                                               Average                                                     Number of
                                       Work     labor                                                        U.S.-
               Action                  hours   rate per       Parts cost          Cost per  airplane       registered              Fleet cost
                                                 hour                                                      airplanes
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Detailed inspection.................       1        $65  None                 $65                                 522  $33,930.
HFEC inspection.....................       4         65  None                 $260, per inspection cycle          522  $135,720, per inspection cycle.
Replace fitting.....................       2         65  $1,674               $1,804                              522  $941,688.
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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):

2005-20-16 Boeing: Amendment 39-14310. Docket No. FAA-2005-21138; 
Directorate Identifier 2004-NM-131-AD.

Effective Date

    (a) This AD becomes effective November 9, 2005.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to Boeing Model 737-100, -200, and -200C 
series airplanes; line numbers 1 through 1585 inclusive; 
certificated in any category.

Unsafe Condition

    (d) This AD was prompted by reports of damage to the lugs of 
certain inboard attach fittings of the leading edge slat tracks. We 
are issuing this AD to prevent a lifted slat, which, if the airplane 
performs any non-normal maneuver during takeoff or landing at very 
high angles of attack, could lead to the loss of the slat and 
reduced 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 the 
Accomplishment Instructions of Boeing Special Attention Service 
Bulletin 737-57-1273, Revision 2, dated October 30, 2003; unless 
otherwise specified in this AD.

Inspections

    (g) Prior to the accumulation of 7,000 total flight cycles or 
within 12 months after the effective date of this AD, whichever 
occurs later, perform a one-time detailed inspection for cracking 
and damage of the inboard attach fittings at slats 2 and 5 of the 
wing leading edge in accordance with the service bulletin.

    Note 1: For the purposes of this AD, a detailed inspection is 
``An intensive visual examination of a specific structural area, 
system, installation, or assembly to detect damage, failure, or 
irregularity. Available lighting is normally supplemented with a 
direct source of good lighting at intensity deemed appropriate by 
the inspector. Inspection aids such as mirror, magnifying lenses, 
etc., may be used. Surface cleaning and elaborate access procedures 
may be required.''

    (1) If any crack or damage is found, replace the cracked inboard 
attach fitting in accordance with paragraph (h) of this AD.
    (2) If no crack or damage is found, within 4,500 flight cycles 
or 18 months after the detailed inspection required by paragraph (g) 
of this AD, whichever occurs first, perform a high-frequency eddy 
current (HFEC) inspection for cracking of the lugs of the inboard 
attach fittings in accordance with the service bulletin. If no crack 
is found, repeat the HFEC inspection at intervals not to exceed 
4,500 flight cycles.

Replacement of Fittings

    (h) Replace the aluminum inboard attach fittings with new, 
improved steel fittings at the applicable compliance time in 
paragraph (h)(1) or (h)(2) of this AD in accordance with the service 
bulletin. Replacement of any aluminum fitting with a new, improved 
steel fitting terminates the one-time detailed inspection and the 
repetitive HFEC

[[Page 58007]]

inspections required by paragraph (g) of this AD for that fitting.
    (1) If any crack or damage is found during any inspection 
required by paragraphs (g) or (i) of this AD, before further flight.
    (2) If no crack or damage is found during any inspection 
required by paragraph (g) or (i) of this AD, within 30,000 flight 
cycles or within 120 months after the effective date of this AD, 
whichever occurs first.

Concurrent Service Bulletin

    (i) For airplanes listed in Group 2 of the service bulletin: 
Prior to or during the one-time detailed inspection for cracking or 
damage required by paragraph (g) of this AD or during replacement of 
the fitting required by paragraph (h) of this AD, whichever occurs 
first, perform a detailed inspection on slats 2 and 5 for 
interference of the slat tab support clips with the slat track 
attach fittings and trim the support clips to eliminate any 
interference with the attach fittings as applicable; in accordance 
with Figure 3 of the Accomplishment Instructions of Boeing Service 
Bulletin 737-57-1080, Revision 3, dated September 24, 1992; and 
replace any cracked or damaged aluminum attach fitting with a new, 
improved steel fitting in accordance with paragraph (h) of this AD.

Actions Accomplished Per Previous Issue of Service Bulletin

    (j) Actions accomplished before the effective date of this AD in 
accordance with Boeing Service Bulletin 737-57-1080, dated September 
10, 1973; Revision 1, dated February 25, 1983; or Revision 2, dated 
August 24, 1989; are considered acceptable for compliance with the 
corresponding actions specified in paragraph (i) of this AD.

Alternative Methods of Compliance (AMOCs)

    (k)(1) The Manager, Seattle Aircraft Certification Office (ACO), 
FAA, has the authority to approve AMOCs for this AD, if requested in 
accordance with the procedures found in 14 CFR 39.19.
    (2) An AMOC that provides an acceptable level of safety may be 
used for any repair required by this AD, if it is approved by an 
Authorized Representative for the Boeing Commercial Airplane 
Delegation Option Authorization Organization who 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.
    (3) Before using any AMOC approved in accordance with 14 CFR 
39.19 on any airplane to which the AMOC applies, notify the 
appropriate principal inspector in the FAA Flight Standards 
Certificate Holding District Office.

Material Incorporated by Reference

    (l) You must use Boeing Special Attention Service Bulletin 737-
57-1273, Revision 2, dated October 30, 2003; and Boeing Service 
Bulletin 737-57-1080, Revision 3, dated September 24, 1992; as 
applicable; 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 these documents 
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 
Docket Management Facility, U.S. Department of Transportation, 400 
Seventh Street SW., room PL-401, Nassif Building, Washington, DC; on 
the Internet at http://dms.dot.gov; or at the National Archives and 
Records Administration (NARA). For information on the availability 
of this material at the NARA, call (202) 741-6030, or go to http://www.archives.gov/federal-register/cfr/ibr-locations.html.

    Issued in Renton, Washington, on September 26, 2005.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 05-19871 Filed 10-4-05; 8:45 am]
BILLING CODE 4910-13-P