[Federal Register Volume 71, Number 113 (Tuesday, June 13, 2006)]
[Rules and Regulations]
[Pages 33992-33994]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 06-5287]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2006-24245; Directorate Identifier 2005-NM-166-AD; 
Amendment 39-14643; AD 2006-12-17]
RIN 2120-AA64


Airworthiness Directives; Boeing Model 737-200C Series 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 737-200C series airplanes. That 
AD currently requires a one-time external detailed inspection for 
cracking of the fuselage skin in the lower lobe cargo compartment; 
repetitive internal detailed inspections for cracking of the frames in 
the lower lobe cargo compartment; repair of cracked parts; and 
terminating action for the repetitive internal detailed inspections. 
This new AD restates the requirements of the existing AD and adds a 
requirement to perform repetitive detailed inspections of the body 
station (BS) 360 and BS 500 fuselage frames, after accomplishing the 
terminating action, and repair if necessary. This AD results from 
multiple reports that the existing AD is not fully effective in 
preventing cracks in the BS 360 and BS 500 fuselage frames. We are 
issuing this AD to detect and correct cracking of the fuselage frames 
from BS 360 to BS 500B, which could lead to loss of the cargo door 
during flight and consequent rapid decompression of the airplane.

DATES: This AD becomes effective July 18, 2006.
    On August 9, 1993 (58 FR 36863, July 9, 1993), the Director of the 
Federal Register approved the incorporation by reference of certain 
publications listed in the AD.

ADDRESSES: You may examine the AD docket on the Internet at http://

[[Page 33993]]

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: Howard Hall, Aerospace Engineer, 
Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office, 
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 
917-6430; 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 supersedes AD 99-12-08, amendment 39-
11192 (64 FR 31488, June 11, 1999). The existing AD applies to all 
Boeing Model 737-200C series airplanes. That NPRM was published in the 
Federal Register on March 30, 2006 (71 FR 16063). That NPRM proposed to 
require a one-time external detailed inspection for cracking of the 
fuselage skin in the lower lobe cargo compartment; repetitive internal 
detailed inspections for cracking of the frames in the lower lobe cargo 
compartment; repair of cracked parts; and terminating action for the 
repetitive internal detailed inspections. That NPRM also proposed to 
add a requirement to perform repetitive detailed inspections of the 
body station (BS) 360 and BS 500 fuselage frames, after accomplishing 
the terminating action, and repair if necessary.

Comments

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

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 as proposed.

Costs of Compliance

    There are about 90 airplanes of the affected design in the 
worldwide fleet. This AD will affect about 18 airplanes of U.S. 
registry.
    The modification required by AD 99-12-08, and retained in this AD, 
takes approximately 160 work hours per airplane to accomplish, at an 
average labor rate of $80 per work hour. Required parts cost about 
$5,500 per airplane. Based on these figures, the estimated cost of the 
currently required modification for U.S. operators is $329,400, or 
$18,300 per airplane.
    The new inspections will take about 3 work hours per airplane, at 
an average labor rate of $80 per work hour. Based on these figures, the 
estimated cost of the new inspections specified in this AD for U.S. 
operators is $4,320, or $240 per airplane, per inspection 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 
removing amendment 39-11192 (64 FR 31488, June 11, 1999) and by adding 
the following new airworthiness directive (AD):

2006-12-17 Boeing: Amendment 39-14643. Docket No. FAA-2006-24245; 
Directorate Identifier 2005-NM-166-AD.

Effective Date

    (a) This AD becomes effective July 18, 2006.

Affected ADs

    (b) This AD supersedes AD 99-12-08.

Applicability

    (c) This AD applies to all Boeing Model 737-200C series 
airplanes, certificated in any category.

Unsafe Condition

    (d) This AD results from multiple reports that the modification 
required by AD 99-12-08 is not fully effective in preventing cracks 
in the body station (BS) 360 and BS 500 fuselage frames. We are 
issuing this AD to detect and correct cracking of the fuselage 
frames from BS 360 to BS 500B, which could lead to loss of the cargo 
door during flight and consequent rapid decompression 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.

[[Page 33994]]

Restatement of Requirements of AD 99-12-08

One-Time External Detailed Inspection

    (f) Prior to the accumulation of 29,000 total flight cycles or 
within 250 flight cycles after August 9, 1993 (the effective date AD 
93-13-02, amendment 39-8615, which was superseded by AD 99-12-08), 
whichever occurs later, accomplish an external detailed inspection 
to detect cracks of the fuselage skin between stringers 19 left and 
25 left and at BS 360 to BS 540, in accordance with Boeing Alert 
Service Bulletin 737-53A1160, dated October 24, 1991; or Boeing 
Service Bulletin 737-53A1160, Revision 1, dated April 29, 1993. If 
any crack is found, prior to further flight, accomplish the 
requirements of paragraphs (f)(1) and (f)(2) of this AD.
    (1) Perform an internal detailed inspection to detect cracks of 
the frames between stringers 19 left and 25 left and at BS 360 to BS 
500B, in accordance with either service bulletin.
    (2) Repair all cracks in accordance with a method approved by 
the Manager, Seattle Aircraft Certification Office (ACO), Transport 
Airplane Directorate, FAA.

Internal Detailed Inspections

    (g) Within 3,000 flight cycles after completing the requirements 
of paragraph (f) of this AD, unless accomplished within the last 
6,000 flight cycles prior to August 9, 1993, perform an internal 
detailed inspection to detect cracks of the frames between stringers 
19 left and 25 left and at body stations 360 to 500B, in accordance 
with Boeing Alert Service Bulletin 737-53A1160, dated October 24, 
1991; or Boeing Service Bulletin 737-53A1160, Revision 1, dated 
April 29, 1993. Thereafter, repeat the internal detailed inspection 
at intervals not to exceed 9,000 flight cycles. If any crack is 
found during any inspection required by this paragraph, before 
further flight, repair as specified in paragraph (g)(1) or (g)(2) of 
this AD, as applicable.
    (1) If any crack is found that does not exceed the limits 
specified in the Boeing 737 Structural Repair Manual (SRM), repair 
the crack in accordance with a method approved by the Manager, 
Seattle ACO; or in accordance with the procedures specified in 
paragraph (k)(4) of this AD. The SRM is one approved source of 
information for accomplishing the requirements of this paragraph. 
Repeat the internal detailed inspection thereafter at intervals not 
to exceed 9,000 flight cycles.
    (2) If any crack is found that exceeds the limits specified in 
the SRM, repair the crack in accordance with a method approved by 
the Manager, Seattle ACO; or in accordance with the procedures 
specified in paragraph (k)(4) of this AD. Repeat the internal 
detailed visual inspection thereafter at intervals not to exceed 
9,000 flight cycles.

Install Doublers

    (h) Prior to the accumulation of 75,000 total flight cycles, or 
within 3,000 flight cycles after July 16, 1999 (the effective date 
of AD 99-12-08), whichever occurs later, install doublers on the 
specified frames located between stringers 19 left and 25 left from 
BS 360 to BS 500B, in accordance with Boeing Service Bulletin 737-
53A1160, Revision 1, dated April 29, 1993. Installing these doublers 
on the specified fuselage frames ends the repetitive inspections 
required by paragraphs (f) and (g) of this AD.

New Requirements of This AD

Repetitive Inspection of Certain Frames

    (i) Within 9,000 flight cycles after accomplishing the 
modification required by paragraph (h) of this AD, or within 4,500 
flight cycles after the effective date of this AD, whichever occurs 
later, perform an internal detailed inspection to detect cracking in 
the fuselage frame at BS 360 and the fuselage frame at BS 500, 
between stringers 19 left and 25 left, in accordance with Boeing 
Alert Service Bulletin 737-53A1160, dated October 24, 1991; or 
Boeing Service Bulletin 737-53A1160, Revision 1, dated April 29, 
1993. Thereafter, repeat the internal detailed inspection of the BS 
360 and BS 500 frames at intervals not to exceed 9,000 flight 
cycles.
    (j) If any crack is found during any inspection required by 
paragraph (i) of this AD, before further flight, repair the crack 
using a method approved in accordance with the procedures specified 
in paragraph (k) of this AD.

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

Alternative Methods of Compliance (AMOCs)

    (k)(1) The Manager, Seattle ACO, has the authority to approve 
AMOCs for this AD, if requested in accordance with the procedures 
found in 14 CFR 39.19.
    (2) 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.
    (3) AMOCs approved previously in accordance with AD 99-12-08, 
including AMOCs approved previously in accordance with AD 93-13-02, 
are approved as AMOCs for the corresponding provisions specified in 
paragraphs (f), (g), and (h) of this AD.
    (4) 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 Airplanes 
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.

Material Incorporated by Reference

    (l) You must use Boeing Alert Service Bulletin 737-53A1160, 
dated October 24, 1991; or Boeing Service Bulletin 737-53A1160, 
Revision 1, dated April 29, 1993, 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 on August 9, 1993 (58 
FR 36863, July 9, 1993). 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/code_of_federal_regulations/ibr_locations.html.

    Issued in Renton, Washington, on June 5, 2006.
Kalene C. Yanamura,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 06-5287 Filed 6-12-06; 8:45 am]
BILLING CODE 4910-13-P