[Federal Register: April 7, 2005 (Volume 70, Number 66)]
[Rules and Regulations]
[Page 17600-17603]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr07ap05-8]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2004-19003; Directorate Identifier 2003-NM-245-AD;
Amendment 39-14044; AD 2005-07-19]
RIN 2120-AA64
Airworthiness Directives; Boeing Model 737-100, -200C, -300, -
400, and -500 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 all
Boeing Model 737-100, -200, -200C, -300, -400, and -500 series
airplanes. This AD requires repetitive inspections for cracks in the
fuselage skin, doubler, bearstrap, and frames surrounding the main,
forward, and aft cargo doors; and repair of any cracking. This AD also
requires inspections of certain existing repairs for cracking, and
related corrective action if cracking is found. This AD is prompted by
reports of multiple fatigue cracks in the fuselage skin and bonded skin
doubler, bearstrap, and doorway frames surrounding the forward and aft
cargo doors. We are issuing this AD to find and fix fatigue cracking in
the fuselage skin, doubler, bearstrap, and frames, which could result
in reduced structural integrity of the frames, possible loss of a cargo
door, and consequent rapid decompression of the fuselage.
DATES: This AD becomes effective May 12, 2005.
The incorporation by reference of a certain publication listed in
the AD is approved by the Director of the Federal Register as of May
12, 2005.
ADDRESSES: For service information identified in this AD, contact
Boeing Commercial Airplanes, P.O. Box 3707, Seattle, Washington 98124-
2207. You can examine this information 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
.
Docket: The AD docket contains the proposed AD, comments, and any
final disposition. You can examine the 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 U.S.
Department of Transportation, 400 Seventh Street, SW., room PL-401,
Washington, DC. This docket number is FAA-2004-19003; the directorate
identifier for this docket is 2003-NM-245-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: The FAA proposed to amend 14 CFR Part 39
with an AD for all Boeing Model 737-100, -200, -200C, -300, -400, and -
500 series airplanes. That action, published in the Federal Register on
September 7, 2004 (69 FR 54058), proposed to require repetitive
inspections for cracks in the fuselage skin, doubler, bearstrap, and
frames surrounding the main, forward, and aft cargo doors; and repair
of any cracking. That action also proposed to require inspections of
certain existing repairs for cracking, and related corrective action if
cracking is found.
Comments
We provided the public the opportunity to participate in the
development of this AD. We have considered the comments that have been
submitted on the proposed AD.
Supportive Comment
One commenter states that the proposed AD will affect only its 737-
200C and -400 fleets, and adds that the proposed detailed inspections
and compliance intervals will allow compliance at heavy check
maintenance visits. The commenter stipulates that these requirements
are acceptable provided there are adequate replacement parts available
if discrepancies are found.
[[Page 17601]]
We have discussed the issue of obtaining replacement parts with the
airplane manufacturer and we anticipate no difficulty in getting the
parts to accomplish repairs.
Request for Credit for Accomplishing AD 93-14-10
One commenter, the airplane manufacturer, asks that we add a
sentence to paragraph (f) of the proposed AD that gives credit for
accomplishing the inspections and repairs required by AD 93-14-10,
amendment 39-8634 (58 FR 43547, August 17, 1993). The commenter states
that the requirements of the proposed AD are equivalent to, or more
conservative than, the requirements in AD 93-14-10.
We agree with the commenter that accomplishing the requirements in
paragraph (f) of the proposed AD ends the requirements in AD 93-14-10
(referenced as related rulemaking in the preamble of the proposed AD).
As specified in the preamble of the proposed AD, during structural
inspections, cracks were found in the bearstrap under the fuselage
frame flanges at the edges of the forward cargo door. In two cases,
cracks were found in the fuselage frames of the aft cargo door where
steel repair doublers had been installed using the requirements of AD
93-14-10; therefore, the requirements in this AD exceed the
requirements of AD 93-14-10. We have changed paragraph (f) of this AD
by adding credit for previously accomplishing AD 93-14-10.
Request To Add Inspection Type to Paragraph (f) of the Proposed AD
The same commenter states that the first sentence in paragraph (f)
specifies, in part, ``Do the applicable detailed, general visual, and
low and high frequency eddy current inspections for cracks * * *'' The
commenter asks that a reference to the mid-frequency eddy current
(MFEC) inspection be added to paragraph (f). The commenter notes that
this inspection is specified in the referenced service bulletin.
We agree with the commenter that the MFEC inspection should be
added to paragraph (f), for clarification. An internal MFEC inspection
is specified in the referenced service bulletin as an option to
accomplishing the detailed visual inspections, and would extend the
compliance time for the repetitive inspections, but was not identified
in the proposed AD. Paragraph (f) of the proposed AD specified doing
the ``applicable'' inspections for cracks as specified in the
referenced tables. However, to clarify the type of inspection, we have
changed paragraph (f) of this final rule to include the MFEC
inspection.
Request for Clarification of Location of Inspections for Existing
Repairs
One commenter asks for clarification regarding accomplishing
inspections of existing repairs around the cargo doors in accordance
with the referenced service bulletin. The commenter states that it is
unclear which inspection is required if repairs are of a different
configuration than those referenced in the figures in the service
bulletin. The commenter notes, for example, that a repair of the cargo
door lower corner per Boeing Structural Repair Manual 737-100/200,
Figure 46, Detail IV, does not match the Figure 8 repair in the service
bulletin. The commenter adds that verbiage needs to be added clarifying
whether the ``intent'' of the service bulletin is to accomplish a MFEC
inspection of all outer row fasteners of the repair doubler, no matter
what the configuration.
We agree that clarification is necessary. The repairs shown in
Figures 8, 9, and 10 of the referenced service bulletin are conceptual
illustrations of typical doubler/tripler type repairs. These figures
are intended to indicate that the location of the detailed visual or
MFEC inspections for cracking is the skin or bearstrap at the outer row
fasteners common to the outer edge of the repair. We have added a note
after paragraph (f) of the final rule for further clarification.
Request for Certain Repair Instructions
One commenter states that repair instructions that are similar to
those currently available for Model 737-100 and -200 series airplanes
for damaged skin, doubler, and bearstrap around the cargo doors should
also be available for Model 737-300, -400, and -500 series airplanes.
The commenter adds that it is crucial to limit downtime of aircraft as
much as possible, an coordinating repair procedures with Boeing extends
the out-of-service time for affected airplanes.
We agree that repair instructions should be made available for
Model 737-300, -400 and -500 series airplanes. However, until repair
instructions are published for Model 737-300, -400 and -500 series
airplanes, the repair must be accomplished according to a method
approved by the Manager, Settle Aircraft Certification Office or an
Authorized Representative for the Boeing Delegation Option
Authorization (DOA) Organization. Repair procedures have been developed
for incorporation into the next revision of the 737-300/400/500 SRM and
will be submitted to us by Boeing soon. As provided by paragraph (i) of
this AD, we will consider approving these repairs as an alternative
method of compliance for paragraph (g) of this AD. We have made no
change to the final rule in this regard.
Clarification of Applicability
One commenter asks why the proposed AD isn't applicable to Model
737-300C series airplanes with a main cargo door installed by PEMCO.
The commenter notes that the proposed AD includes Model 737-200C series
airplanes with a main cargo door, and asks if excluding the 737-300C is
normal.
We acknowledge the commenter's concern and offer clarification. The
proposed AD is applicable to Model 737-100, -200, -200C, -300, -400, -
500 series airplanes, including airplanes modified to include a main
cargo door. We infer that the commenter's reference to a ``Model 737-
300C'' is an informal designation for a Model 737-300 series airplane
that has been modified to include a main cargo door per a supplemental
type certificate. However, no model 737-300C series airplane is
identified in the type certificate data sheet. Thus, an airplane with
that configuration would be subject to the AD requirements for Model
737-300 series airplanes. In comparison, the Model 737-200C series
airplane is identified in the type certificate data sheet.
Explanation of Changer to Proposed AD
Boeing has received a DOA. We have revised paragraph (i)(2) of this
final rule to delegate the authority to approve an alternative method
of compliance for any repair required by this AD to the Authorized
Representative for the Boeing DOA Organization rather than the
Designated Engineering Representative.
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 change 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 3,132 airplanes of the affected design in the
worldwide fleet. We estimate that 870 airplanes of U.S. registry will
be affected by this AD. We provide the following cost estimates to
[[Page 17602]]
comply with this AD, per inspection cycle:
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Hourly Cost per
Group Work hours labor rate Parts airplane
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1.......................................................... 24 $65 $0 $1,560
2 and 4.................................................... 28 65 0 1,820
3 and 5.................................................... 30 65 0 1,950
6 and 7.................................................... 28 65 0 1,820
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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. 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, Incorporated 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 FAA amends Sec. 39.13 by adding the following new airworthiness
directive (AD):
2005-07-19 Boeing: Amendment 39-14044. Docket No. FAA-2004-19003;
Directorate Identifier 2003-NM-245-AD.
Effective Date
(a) This AD becomes effective May 12, 2005.
Affected ADs
(b) None.
Applicability
(c) This AD applies to all Model 737-100, -200, -200C, -300, -
400, and -500 series airplanes; certified in any category.
Unsafe Condition
(d) This AD was prompted by reports of multiple fatigue cracks
in the fuselage skin and bonded skin doubler, bearstrap, and doorway
frames surrounding the forward and aft cargo doors. We are issuing
this AD to find and fix fatigue cracking in the fuselage skin,
doubler, bearstrap, and frames, which could result in reduced
structural integrity of the frames, possible loss of a cargo door,
and consequent rapid decompression of the fuselage.
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.
Initial and Repetitive Inspections/Corrective Action
(f) Do the applicable detailed, general visual, and low-, mid-,
and high-frequency eddy current inspections for cracks in the
fuselage skin, doubler, bearstrap, and frames surrounding the main,
forward, and aft cargo doors, and for cracks in existing repairs, as
specified in Tables 1, 2, and 3, as applicable, of paragraph 1.E.,
``Compliance,'' of Boeing Alert Service Bulletin 737-53A1228, dated
July 10, 2003. Do the inspections at the initial compliance times
listed in Tables 1, 2, and 3, as applicable, of paragraph 1.E.,
``Compliance,'' of the service bulletin; except, where the service
bulletin specifies a compliance time after the service bulletin
date, this AD requires compliance within the specified compliance
time after the effective date of this AD. Do the inspections in
accordance with the Accomplishment Instructions of the service
bulletin. Repeat the inspections within the repetitive inspection
intervals listed in Tables 1, 2, 3 of paragraph 1.E.,
``Compliance,'' of the service bulletin. Accomplishing the
requirements in this paragraph ends the requirements in AD 93-14-10,
amendment 39-8634 (58 FR 43547. August 17, 1993).
Note 1: At existing repairs around the forward and aft cargo
door cutouts: The location for the specified detailed or mid-
frequency eddy current inspections for cracking of the skin or
bearstrap is at the outer row of fasteners common to the repair, as
illustrated in Figures 8, 9, and 10 of Boeing Alert Service Bulletin
737-53A1228, dated July 10, 2003.
(g) If any crack is found during any inspection: Repair before
further flight in accordance with the Accomplishment Instructions of
Boeing Alert Service Bulletin 737-53A1228, dated July 10, 2003.
Where the service bulletin specifies contacting the manufacturer for
disposition of certain repair conditions, repair before further
flight in accordance with a method approved by the Manager, Seattle
Aircraft Certification Office (ACO), FAA; or an Authorized
Representative for the Boeing Delegation Option Authorization (DOA)
Organization who has been authorized by the Manager, Seattle ACO, to
make such findings. For a repair method to be approved, the approval
must specifically refer to this AD.
No Reporting Required
(h) Although the service bulletin referenced in this AD
recommends reporting any discrepancies to the manufacturer, this AD
does not include that requirement.
Alternative Methods of Compliance (AMOCs)
(i)(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) 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
[[Page 17603]]
DOA Organization who has been authorized by the Manager, Seattle
ACO, to make those findings.
Material Incorporated by Reference
(j) You must use Boeing Alert Service Bulletin 737-53A1228,
dated July 10, 2003, to perform the actions that are required by
this AD, unless the AD specifies otherwise. The Director of the
Federal Register approves the incorporation by reference of this
document in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. For
copies of the service information, contact Boeing Commercial
Airplanes, P.O. Box 3707, Seattle, Washington 98124-2207. For
information on the availability of this material at the National
Archives and Records Administration (NARA), call (202) 741-6030, or
go to http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html.
You may view the AD docket at the
Docket Management Facility, U.S. Department of Transportation, 400
Seventh Street, SW., room PL-401, Nassif Building, Washington, DC.
Issued in Renton, Washington, on March 30, 2005.
Kalene C. Yanamura,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 05-6763 Filed 4-6-05; 8:45 am]
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