[Federal Register: September 27, 2005 (Volume 70, Number 186)]
[Rules and Regulations]
[Page 56351-56355]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr27se05-5]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2005-20627; Directorate Identifier 2004-NM-39-AD;
Amendment 39-14290; AD 2005-19-25]
RIN 2120-AA64
Airworthiness Directives; Boeing Model 737-100, -200, -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
certain Boeing Model 737-100, -200, -200C, -300, -400, and -500 series
airplanes. This AD requires repetitive eddy current inspections for
cracks of the countersunk rivet holes in the lower lobe, adjacent to
the radio altimeter cutouts; additional inspections, for certain
airplanes, for cracks and/or corrosion; and further investigative and
corrective action if any crack is found. This AD also provides an
optional terminating action for the repetitive inspections. This AD
results from reports of cracks in the fuselage skin of the lower lobe.
We are issuing this AD to detect and correct fatigue cracks of the
countersunk rivet holes, which could result in cracks of the fuselage
[[Page 56352]]
skin of the lower lobe, and consequent rapid depressurization of the
cabin.
DATES: This AD becomes effective November 1, 2005.
The Director of the Federal Register approved the incorporation by
reference of certain publications listed in the AD as of November 1,
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: Sue Lucier, Aerospace Engineer,
Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office,
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425)
917-6438; 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 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. This docket number is FAA-2005-20627; the
directorate identifier for this docket is 2004-NM-39-AD.
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, -200C, -300, -400, and -500 series airplanes. That NPRM
was published in the Federal Register on March 17, 2005 (70 FR 12982).
That NPRM proposed to require repetitive eddy current inspections for
cracks of the countersunk rivet holes in the lower lobe, adjacent to
the radio altimeter cutouts; additional inspections, for certain
airplanes, for cracks and/or corrosion; and further investigative and
corrective action if any crack is found. That NPRM also proposed to
provide an optional terminating action for the repetitive inspections.
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.
Request to Add Note to Provide Inspection Deviations for Existing
Repairs
One commenter, an airplane operator, states that paragraph (g) of
the NPRM does not address inspection deviations for airplanes that
already have the repair doubler installed in accordance with Boeing
Service Bulletin 737-53-1117. The commenter observes that, as the
paragraph is currently worded, operators of these airplanes would be
required to do an eddy current inspection in accordance with Part I of
Boeing Special Attention Service Bulletin 737-53-1230, dated June 13,
2002. The commenter points out that operators of these airplanes would
be forced to remove the doubler in order to do the eddy current
inspection. The commenter notes that the section of the NPRM titled
``Relevant Service Information'' describes what to do for existing
repairs, and states that this section matches Part II, Item 3, Note (a)
of Boeing Special Attention Service Bulletin 737-53-1230. The commenter
proposes that a similar note be added to paragraph (g) of the NPRM to
provide inspection deviations for existing repairs.
We partially agree with the commenter. We agree that paragraph (g)
of the NPRM is unclear with regard to the inspection options for the
body station (BS) 390 cutout that has been previously modified in
accordance with Boeing Service Bulletin 737-53-1117, Revision 1, dated
April 6, 1989. If an operator has removed the doubler for other
reasons, the current description in paragraph (g) of the NPRM would be
sufficient; however, it would be beneficial to operators if the final
rule provided optional inspections that could be performed without
removing the doubler. We disagree with using the exact wording of Part
II, Item 3, Note (a) of Boeing Special Attention Service Bulletin 737-
53-1230, dated June 13, 2002. The instructions in that note describe
specific actions affiliated with the preventive modification. The
preventive modification, which includes inspection, can be accomplished
in lieu of the initial inspection and will terminate ongoing
inspections for that cutout only. However, we have revised paragraph
(g) of the final rule to address inspection deviations for airplanes
that already have the repair doubler.
Request to Clarify Wording in Paragraph (i)
Two commenters request that we reword paragraph (i) of the NPRM to
make the requirements more clear. One commenter states that the
conditions listed in paragraph (i) do not clearly state that all three
conditions need to be met. The other commenter states that, with the
current wording in paragraph (i), it is unclear if the inspections in
Table 1 are required if one or both of the following conditions occur:
A crack at BS 390, and an external doubler not installed. The commenter
then suggests that paragraph (i) of the NPRM be revised as follows:
``For any airplane in Group 1, 2, 3, 4, or 5 of the special attention
service bulletin, before or at the same time as the repair in paragraph
(h) of this AD, inspect in accordance with Table 1 of this AD if one of
the following conditions exist: (1) A skin crack at the cutout at BS
390 was found during any inspection including inspections required by
paragraphs (g), (h), or (j) of this AD, or (2) an external repair
doubler installed in accordance with Boeing Service Bulletin 737-53-
1117, Revision 1, dated April 6, 1989, has not previously been
installed.''
We partially agree. We agree that there is confusion in the
interpretation of the requirements. The confusion is because the repair
doubler installed in accordance with Boeing Service Bulletin 737-53-
1117, which is not mandated by this final rule, is on an adjacent piece
of fuselage skin, and extends into the area addressed by the NPRM.
Boeing Special Attention Service Bulletin 737-53-1230 does not clearly
address this additional configuration, so we agree that we should
provide further clarification in the final rule so that operators have
adequate instructions for compliance. We disagree with the exact
wording change that the commenter proposes because all of the
conditions must exist to perform the additional inspections addressed
by paragraph (i). We have revised paragraph (i) of the final rule to
provide the necessary clarification. This revision made it necessary to
add new paragraphs (i)(1) and (i)(2) to the final rule. We have re-
lettered the subsequent paragraphs accordingly.
Request to Add Requirement to ``Pre-Form'' the External Doubler
One commenter, the manufacturer, suggests that we add a requirement
to ``pre-form'' the external doubler to the contour of the airplane
prior to installation. The commenter states the repair and modification
instruction in Boeing Service Bulletin 737-53-1117 do
[[Page 56353]]
not specify a requirement to contour the repair or modification
doublers. These doublers are 0.1 inch or 0.08 inch thick respectively,
which may create some pull-up pre-stresses in the skin during
installation unless they are pre-formed. The commenter points out that
the skin in this area is 0.063 inch thick, so the concern for pre-
stress is minimal. However, in the interest of time, in lieu of issuing
a revision to the service bulletin to address the pre-form issue, the
commenter suggests that we add this requirement to the final rule. The
commenter states that there have not been any reports of cracks or
other discrepancies in service from these doublers.
We disagree with the commenter. This rule addresses issues
associated with safety related cracking that are not addressed by other
mandated programs. The commenter states that this lack of ``pre-
forming'' information has not lead to safety related cracking.
Therefore, we conclude that this ``pre-forming'' requirement can be
categorized as a product improvement to the existing service bulletin.
This information is best included in the next revision of the service
bulletin, and subsequently proposed as an alternative method of
compliance. In addition, the repair/modification done in accordance
with Boeing Service Bulletin 737-53-1117, Revision 1, dated April 6,
1989, is subject to the Repair Assessment Program operational rule, and
would receive inspections to detect any safety related cracking caused
by lack of pre-forming. We have not changed the final rule in this
regard.
Request To Clarify Inspection Requirements in Paragraph (h)
One commenter states that the reference in paragraph (i) of the
NPRM to inspection requirements in paragraph (h) of the NPRM is
incorrect because paragraph (h) provides for a repair, not an
inspection instruction.
We disagree with the commenter. Paragraph (h) states, in part: ``*
* *'' repair the area by doing all applicable corrective and further
investigative actions ``* * *.'' The further investigative actions are
inspections that are done as part of the repair. We have not changed
the final rule in this regard.
Request To Clarify ``Relevant Service Information''
One commenter requests that we clarify the ``Relevant Service
Information'' section of the NPRM. The commenter states that the
sentence that says, ``for these airplanes, the preventive modification
is removing the ten fasteners.* * *'' does not indicate clearly that
the preventive modification is at BS 390. The commenter suggests that
we add a reference to BS 390 to that sentence.
We agree with the commenter that clarifying the sentence would be
helpful. However, since that section of the preamble does not reappear
in the final rule, no change to the final rule is necessary.
Request To Fix Typographical Error
One commenter requests that we correct the spelling of the word
``either'' in the heading in Table 1 of the NPRM.
We agree with the commenter. However, this typographical error
appeared only in the version of the NPRM that appeared in the
Regulatory Guidance Library. The Federal Register version, which is the
official version of the NPRM, has the word ``either'' spelled
correctly.
Explanation of Further Changes Made To Clarify Requirements for
Airplanes Modified in Accordance With Boeing Service Bulletin 737-53-
1117
Several commenters, noted above, were concerned about issues
related to airplanes that have been previously modified in accordance
with Boeing Service Bulletin 737-53-1117. In light of these several
concerns, we conducted a further review of Boeing Special Attention
Service Bulletin 737-53-1230, dated June 13, 2002, which is the source
of service information for this AD, and which also addresses,
peripherally, airplanes modified in accordance with Boeing Service
Bulletin 737-53-1117. The goal of our review was to determine if
adequate instructions exist in Boeing Special Attention Service
Bulletin 737-53-1230 for these airplanes, and, if we determined that
the instructions were inadequate, to revise the final rule to include
additional clarifying language for operators of these airplanes. We
have concluded that additional clarifying language is necessary. The
additional clarifying language does not increase the scope of work that
was previously described in the NPRM, however it does allow relieving
options for affected operators. The three clarifications included in
the final rule are described below.
1. We have clarified the inspection options for the BS 390 cutout
in paragraph (g) of the final rule, as noted above in ``Request to Add
Note to Provide Inspection Deviations for Existing Repairs.''
2. We have clarified paragraph (h) of the final rule to include
instructions for repairs at BS 390 ``with doubler installed.''
Airplanes in this configuration are not addressed in Boeing Special
Attention Service Bulletin 737-53-1230, dated June 13, 2002, Table C,
Part III--Repair. Therefore, paragraph (h), though adequate in the
NPRM, has been revised in the final rule to specifically require repair
of these airplanes according to a method approved by the Manager,
Seattle Aircraft Certification Office (ACO), FAA; or according to data
meeting the certification basis of the airplane approved by an
Authorized Representative for the Boeing Delegation Option
Authorization Organization who has been authorized by the Manager,
Seattle ACO, to make those findings.
3. We have clarified paragraph (l) of the final rule (paragraph (j)
of the NPRM) to specify that the inspection of the fastener hole
countersink in accordance with Figure 2 of Boeing Special Attention
Service Bulletin 737-53-1230, dated June 13, 2002, is not required for
modified airplanes. This inspection is part of the preventive
modification procedures in the service bulletin. This area is not
accessible when the external doubler is installed in accordance with
Boeing Service Bulletin 737-53-1117. It is not our intent to require
operators to remove this doubler; therefore the countersink inspection
is not required for these airplanes in the final rule.
Explanation of Additional Changes Made to This AD
We have simplified paragraph (h) and paragraph (k) of this AD
(paragraph (i)(2) of the NPRM) by referring to the ``Alternative
Methods of Compliance (AMOCs)'' paragraph of this AD for repair
methods.
We have also 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.
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
This AD affects about 3,132 airplanes worldwide. The following
table provides the estimated costs for U.S. operators to comply with
this AD.
[[Page 56354]]
Estimated Costs
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Number of U.S.-
Action Work Average labor Parts Cost per registered Fleet cost
hours rate per hour airplane airplanes
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Inspection.................................. 3 $65 No parts required.............. $195 1,004 $195,780
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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):
2005-19-25 Boeing: Amendment 39-14290. Docket No. FAA-2005-20627;
Directorate Identifier 2004-NM-39-AD.
Effective Date
(a) This AD becomes effective November 1, 2005.
Affected ADs
(b) None.
Applicability
(c) This AD applies to Boeing Model 737-100, -200, -200C, -300,
-400, and -500 series airplanes, certificated in any category; as
identified in Boeing Special Attention Service Bulletin 737-53-1230,
dated June 13, 2002.
Unsafe Condition
(d) This AD was prompted by reports of cracks in the lower lobe
fuselage skin of the affected airplanes. We are issuing this AD to
detect and correct fatigue cracks of the countersunk rivet holes,
which could result in cracks of the fuselage skin of the lower lobe,
and consequent rapid depressurization of the cabin.
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 ``special attention service bulletin,'' as used in
this AD, means the Accomplishment Instructions of Boeing Special
Attention Service Bulletin 737-53-1230, dated June 13, 2002.
Repetitive Inspections
(g) Before the airplane accumulates 20,000 total flight cycles,
or within 4,500 flight cycles after the effective date of this AD,
whichever occurs later: Do the inspection in paragraph (g)(1) of
this AD; or, for airplanes with an external repair doubler installed
at body station (BS) 390, do the inspection in paragraph (g)(2) of
this AD in lieu of the inspection in paragraph (g)(1) of this AD for
BS 390 only; inspections at all other body stations must be done in
accordance with paragraph (g)(1) of this AD. Repeat the applicable
inspection thereafter at intervals not to exceed 4,500 flight
cycles.
(1) Do an eddy current inspection for cracks of the surface area
around the satellite holes of the radio altimeter cutouts between BS
390 and BS 450. Do the inspection with the fasteners installed in
accordance with the special attention service bulletin.
(2) For airplanes that have an external repair doubler installed
at BS 390 only, in accordance with Boeing Service Bulletin 737-53-
1117, Revision 1, dated April 6, 1989, do an eddy current inspection
of the external doubler for cracks around the satellite holes of the
radio altimeter cutout; and do an eddy current inspection for cracks
of the fuselage skin along the aft edge of the doubler from S-28L to
S-28R. Do the inspections with the fasteners installed in accordance
with the procedures in Figure 1 of the special attention service
bulletin.
Repair
(h) If any crack is found during any eddy current inspection
required by this AD: Before further flight, repair the area by doing
all applicable corrective and further investigative actions in
accordance with the special attention service bulletin.
Accomplishment of the repair terminates the repetitive inspection
requirements of paragraph (g) of this AD for the repaired area.
Where the special attention service bulletin specifies to contact
Boeing for appropriate action; for instructions about how to repair
certain conditions, including repairs at BS 390 ``with doubler
installed''; or where lack of specific repair instructions exist:
Before further flight, repair using a method approved in accordance
with paragraph (m) of this AD.
Additional Inspection and Repair for Certain Airplanes
(i) For any airplane in Group 1, 2, 3, 4, or 5 of the special
attention service bulletin: Before or at the same time as the
actions in paragraph (h) of this AD, inspect in accordance with
Table 1 of this AD if both conditions in paragraphs (i)(1) and
(i)(2) of this AD exist.
(1) A skin crack at the cutout at BS 390 was found during any
inspection, including the inspections required by paragraphs (g),
(h), and (j) of this AD.
(2) An external repair doubler has not been previously installed
in accordance with Boeing Service Bulletin 737-53-1117, Revision 1,
dated April 6, 1989.
[[Page 56355]]
Table 1.--Service Information
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Inspect in accordance with either--
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The Accomplishment Instructions of
Boeing Service Bulletin 737-53-1117, Figure 17 of the special
Revision 1, dated April 6, 1989-- attention service bulletin--
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A detailed inspection for cracks in the An eddy current inspection for
fuselage lower skin in the area of the cracks of the exhaust port
electronics bay cooling duct cutout. duct cutout edge and the 6
fastener locations;
An eddy current and open-hole
probe inspection for cracks of
the satellite holes; and
A general visual inspection for
corrosion of the area under
the repair.
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Corrective Actions
(j) If any crack at the equipment cooling duct cutout is found
that is less than 3 inches in length during the inspection required
by paragraph (i) of this AD: Before further flight, stop-drill the
crack or cracks and install an external repair doubler in accordance
with the Accomplishment Instructions of Boeing Service Bulletin 737-
53-1117, Revision 1, dated April 6, 1989; or repair in accordance
with Part III of the special attention service bulletin. If the
special attention service bulletin specifies to contact Boeing for
appropriate Action: Before further flight, repair using a method
approved in accordance with paragraph (m) of this AD. Accomplishment
of the repair terminates the repetitive inspection requirements of
paragraph (g) of this AD for the repaired area.
(k) If any corrosion is found, or if any crack is found that is
3 inches in length or greater during the inspection required by
paragraph (i) of this AD: Before further flight, repair using a
method approved in accordance with paragraph (m) of this AD.
Note 1: For the purposes of this AD, a general visual inspection
is: ``A visual examination of an interior or exterior area,
installation, or assembly to detect obvious damage, failure, or
irregularity. This level of inspection is made from within touching
distance unless otherwise specified. A mirror may be necessary to
ensure visual access to all surfaces in the inspection area. This
level of inspection is made under normally available lighting
conditions such as daylight, hangar lighting, flashlight, or
droplight and may require removal or opening of access panels or
doors. Stands, ladders, or platforms may be required to gain
proximity to the area being checked.''
Note 2: 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.''
Optional Terminating Action
(l) Installing preventive modification doublers in accordance
with the special attention service bulletin, including the
additional eddy current inspection with the fasteners removed (with
no crack finding), terminates the repetitive inspection requirements
of paragraph (g) of this AD. Where Figure 2 of the special attention
service bulletin specifies to ``eddy current countersink inspect and
open hole probe inspect the 16 satellite holes,'' and the airplane
has an external repair doubler installed in accordance with the
Accomplishment Instructions of Boeing Service Bulletin 737-53-1117,
Revision 1, dated April 6, 1989; that inspection is not required by
this AD. If any crack is found during the eddy current inspection
specified by this paragraph: Before further flight, discontinue the
preventive modification and do the applicable actions in paragraph
(h) of this AD.
Alternative Methods of Compliance
(m)(1) In accordance with 14 CFR 39.19, the Manager, Seattle
Aircraft Certification Office (ACO), is authorized to approve
alternative methods of compliance (AMOCs) for this AD.
(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 Delegation Option
Authorization Organization who has been authorized by the Manager,
Seattle ACO, to make those findings.
(3) Before using any AMOC approved in accordance with Sec.
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
(n) You must use Boeing Service Bulletin 737-53-1117, Revision
1, dated April 6, 1989; and Boeing Special Attention Service
Bulletin 737-53-1230, dated June 13, 2002; 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/code--of--federal--regulations/
ibr--locations.html.
Issued in Renton, Washington, on September 15, 2005.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 05-18911 Filed 9-26-05; 8:45 am]
BILLING CODE 4910-13-P