Airworthiness Directives; Boeing Model 737-300 and -400 Series Airplanes, 38885-38887 [E8-14475]
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Federal Register / Vol. 73, No. 131 / Tuesday, July 8, 2008 / Rules and Regulations
corrective actions before further flight after
accomplishing the inspections. Repeat the
inspections thereafter at applicable intervals
not to exceed those specified in paragraph
1.E., ‘‘Compliance,’’ of the service bulletin.
Actions According to Previous Issue of
Service Bulletin
BILLING CODE 4910–13–P
(g) Inspections and related investigative
and corrective actions are also acceptable for
compliance with the requirements of
paragraph (f) of this AD if done before the
effective date of this AD in accordance with
Boeing Alert Service Bulletin MD80–53A301,
dated January 9, 2007.
(h)(1) The Manager, Los Angeles 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) 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.
(3) 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, Los Angeles
ACO, to make those findings. For a repair
method to be approved, the repair must meet
the certification basis of the airplane and 14
CFR 25.571, Amendment 45, and the
approval must specifically refer to this AD.
ebenthall on PRODPC60 with RULES
Material Incorporated by Reference
(i) You must use Boeing Alert Service
Bulletin MD80–53A301, Revision 1, dated
May 25, 2007, to do the actions required by
this AD, unless the AD specifies otherwise.
(1) The Director of the Federal Register
approved the incorporation by reference of
this service information under 5 U.S.C.
552(a) and 1 CFR part 51.
(2) For service information identified in
this AD, contact Boeing Commercial
Airplanes, Long Beach Division, 3855
Lakewood Boulevard, Long Beach, California
90846, Attention: Data and Service
Management, Dept. C1–L5A (D800–0024).
(3) You may review copies of the service
information incorporated by reference 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, or go to: https://
www.archives.gov/federal_register/
code_of_federal_regulations/
ibr_locations.html.
14:13 Jul 07, 2008
Jkt 214001
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA–2007–0395; Directorate
Identifier 2007–NM–157–AD; Amendment
39–15588; AD 2008–13–25]
Alternative Methods of Compliance
(AMOCs)
VerDate Aug<31>2005
Issued in Renton, Washington, on June 8,
2008.
Michael Kaszycki,
Acting Manager, Transport Airplane
Directorate, Aircraft Certification Service.
[FR Doc. E8–14472 Filed 7–7–08; 8:45 am]
RIN 2120–AA64
Airworthiness Directives; Boeing
Model 737–300 and –400 Series
Airplanes
Federal Aviation
Administration (FAA), DOT.
ACTION: Final rule.
AGENCY:
SUMMARY: We are adopting a new
airworthiness directive (AD) for certain
Boeing Model 737–300 and –400 series
airplanes. This AD requires testing and
inspecting a certain web panel of the
main wheel well pressure deck to
determine the material type and
thickness; and related investigative and
corrective actions if necessary. This AD
results from several reports indicating
that cracks ranging from 0.8 to 8.0
inches long were found on a certain web
panel of the main wheel well pressure
deck. We are issuing this AD to prevent
fatigue cracking in the web panel of the
main wheel well pressure deck, which
could result in venting and consequent
decompression of the airplane.
DATES: This AD is effective August 12,
2008.
The Director of the Federal Register
approved the incorporation by reference
of a certain publication listed in this AD
as of August 12, 2008.
ADDRESSES: For service information
identified in this AD, contact Boeing
Commercial Airplanes, P.O. Box 3707,
Seattle, Washington 98124–2207.
Examining the AD Docket
You may examine the AD docket on
the Internet at https://
www.regulations.gov; or in person at the
Docket Management Facility between 9
a.m. and 5 p.m., Monday through
Friday, except Federal holidays. The AD
docket contains this AD, the regulatory
evaluation, any comments received, and
other information. The address for the
Docket Office (telephone 800–647–5527)
is the Document Management Facility,
PO 00000
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38885
U.S. Department of Transportation,
Docket Operations, M–30, West
Building Ground Floor, Room W12–140,
1200 New Jersey Avenue, SE.,
Washington, DC 20590.
FOR FURTHER INFORMATION CONTACT:
Wayne Lockett, Aerospace Engineer,
Airframe Branch, ANM–120S, FAA,
Seattle Aircraft Certification Office,
1601 Lind Avenue, SW., Renton,
Washington 98057–3356; telephone
(425) 917–6447; fax (425) 917–6590.
SUPPLEMENTARY INFORMATION:
Discussion
We issued a notice of proposed
rulemaking (NPRM) to amend 14 CFR
part 39 to include an airworthiness
directive (AD) that would apply to
certain Boeing Model 737–300 and –400
series airplanes. That NPRM was
published in the Federal Register on
January 10, 2008 (73 FR 1846). That
NPRM proposed to require testing and
inspecting a certain web panel of the
main wheel well pressure deck to
determine the material type and
thickness; and related investigative and
corrective actions if necessary.
Comments
We gave the public the opportunity to
participate in developing this AD. We
considered the comments received.
Request To Change the Description of
the Unsafe Condition
Boeing asks that the unsafe condition
(end level effect) specified in the
applicable sections of the NPRM be
changed from ‘‘rapid decompression’’ to
‘‘controlled decompression.’’ Boeing
states that the most probable result of
the cracking would be pressure loss or
controlled depressurization. Boeing has
received reports of cracks ranging from
4.5 to 8 inches in the web panel of the
main wheel well pressure deck; the
reports included the following data:
• Cabin crews reported a loud hissing
noise coming from the area below seats
14A, B, and C. No depressurization was
reported.
• The crew reported a loud hissing
noise from the cabin lining on the lefthand side at row 15. The cabin windows
along the left-hand side progressively
frosted up until, after about 2 hours, all
the windows were frosted up between
rows 11 through 17.
• It was reported that it was not
possible to pressurize another airplane.
We partially agree with Boeing. We
agree to change the end level effect of
the unsafe condition by removing the
word ‘‘rapid,’’ since Boeing has
provided data verifying that the
decompression does not happen
quickly. However, we do not agree that
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08JYR1
38886
Federal Register / Vol. 73, No. 131 / Tuesday, July 8, 2008 / Rules and Regulations
ebenthall on PRODPC60 with RULES
the decompression is ‘‘controlled’’
because of the safety implications and
consequences associated with cracking
on a web panel of the main wheel well
pressure deck. We have changed the
applicable sections in this AD
accordingly.
Request To Clarify Certain Compliance
Times
Boeing asks that we clarify the
different compliance times for replacing
discrepant web panels, depending on
the thickness, as specified in Table 1 of
Part 1.E., Compliance, of Boeing Special
Attention Service Bulletin 737–57–
1289, dated June 13, 2007. (The service
bulletin was referenced in the NPRM as
the appropriate source of service
information for accomplishing the
specified actions.) Boeing states that, as
written, paragraphs (g)(1) and (g)(2) of
the NPRM would allow 30 months or
6,000 flight cycles, whichever is later, to
replace discrepant web panels. Boeing
notes that this is acceptable for
discrepant web panels with a material
thickness that is found to be greater than
or equal to 0.037 inch, and less than
0.047 inch; however, for web panels
with a material thickness of less than
0.037 inch the specified compliance
time is before further flight. Boeing adds
that web panels with a material
thickness of less than 0.037 inch do not
meet the ultimate regulatory load
requirements. Boeing also asks that the
related investigative and corrective
actions be clarified.
We agree with Boeing that some
clarification is necessary. Paragraph
(g)(1) of the AD requires accomplishing
all applicable related investigative and
corrective actions before further flight
(which includes replacing any
discrepant web panels) by doing all the
actions specified in the
Accomplishment Instructions of the
service bulletin. The Accomplishment
Instructions do not clearly identify web
panels with a material thickness of less
than 0.037 inch; however, the web
panels are clearly identified in
paragraph 1.E. of the service bulletin.
Paragraph 1.E. specifies replacing web
panels with a material thickness of less
than 0.037 inch, as specified in
paragraph 3.B.7. of the Accomplishment
Instructions of the service bulletin.
Therefore, we have clarified paragraph
(g)(1) of this AD to add that the
corrective actions include replacing any
web panel with a material thickness of
less than 0.037 inch before further
flight. We have also changed paragraph
(g)(2) of this AD to clarify that the
compliance time in that paragraph is
separate from the compliance time
specified in paragraph (g)(1). The
VerDate Aug<31>2005
14:13 Jul 07, 2008
Jkt 214001
related investigative and corrective
actions are defined in the service
information section of the NPRM;
therefore, no change is necessary in this
regard.
Request To Clarify That Additional
Action Is Necessary
Boeing also asks that we change
paragraph (e) of the NPRM to clarify that
additional action is necessary for
operators that inspected web panels
using instructions that were contained
in Boeing Communication messages that
were sent out on January 17, 2006, prior
to the release of the referenced service
bulletin. Boeing states that the messages
were sent to airlines that were operating
airplanes that could have a discrepant
web panel. Boeing adds that following
release of those messages, as part of the
information being developed for release
in the referenced service bulletin, it was
determined that additional details were
necessary to accurately define the
instructions to inspect for discrepant
web panels. Boeing notes that the
additional details, which affect both the
chemical spot test and the ultrasonic
thickness inspections, have been
included in the service bulletin
referenced in the NPRM as the source of
service information for doing the
specified actions; therefore, inspections
accomplished without these additional
steps could result in incorrect
identification of discrepant web panels.
Boeing also suggests that this language
be added to paragraph (e) of the AD.
We acknowledge Boeing’s concerns;
however, paragraph 1.E, ‘‘Compliance,’’
of the referenced service bulletin
specifies that the inspection instructions
contained in the subject Boeing
messages sent out on January 17, 2006,
did not include certain steps. That
section specifies that the chemical spot
test and ultrasonic thickness inspections
must be done again by following the
procedures in the referenced service
bulletin. In addition, paragraph (e) of
this AD states that if the actions
required by this AD have been done
previously, they do not need to be done
again. Therefore, we have made no
change to the AD in this regard.
Conclusion
We reviewed the relevant data,
considered the comments received, and
determined that air safety and the
public interest require adopting the AD
with the changes described previously.
We also determined that these changes
will not increase the economic burden
on any operator or increase the scope of
the AD.
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Fmt 4700
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Costs of Compliance
There are about 31 airplanes of the
affected design in the worldwide fleet.
This AD affects 1 airplane of U.S.
registry. The required tests and
inspections 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 AD for this
U.S. operator is $240.
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
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.
You can find our regulatory
evaluation and the estimated costs of
compliance in the AD Docket.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation
safety, Incorporation by reference,
Safety.
E:\FR\FM\08JYR1.SGM
08JYR1
Federal Register / Vol. 73, No. 131 / Tuesday, July 8, 2008 / Rules and Regulations
Adoption of the Amendment
Accordingly, under the authority
delegated to me by the Administrator,
the FAA amends 14 CFR part 39 as
follows:
I
PART 39—AIRWORTHINESS
DIRECTIVES
1. The authority citation for part 39
continues to read as follows:
I
Authority: 49 U.S.C. 106(g), 40113, 44701.
§ 39.13
[Amended]
2. The FAA amends § 39.13 by adding
the following new AD:
I
2008–13–25 Boeing: Amendment 39–15588.
Docket No. FAA–2007–0395; Directorate
Identifier 2007–NM–157–AD.
Effective Date
(a) This airworthiness directive (AD) is
effective August 12, 2008.
Affected ADs
(b) None.
Applicability
(c) This AD applies to Boeing Model 737–
300 and –400 series airplanes, certificated in
any category; as identified in Boeing Special
Attention Service Bulletin 737–57–1289,
dated June 13, 2007.
Unsafe Condition
(d) This AD results from several reports
indicating that cracks ranging from 0.8 to 8.0
inches long were found on a certain web
panel of the main wheel well pressure deck.
We are issuing this AD to prevent fatigue
cracking in the web panel of the main wheel
well pressure deck, which could result in
venting and consequent decompression of
the airplane.
ebenthall on PRODPC60 with RULES
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.
Testing/Inspecting/Investigative and
Corrective Actions
(f) Within 6 months after the effective date
of this AD: Do a test of the web panel of the
main wheel well pressure deck to determine
the material type, and do an ultrasonic
inspection to determine material thickness,
by doing all the applicable actions specified
in the Accomplishment Instructions of
Boeing Special Attention Service Bulletin
737–57–1289, dated June 13, 2007.
(g) For airplanes on which the web
thickness or material is found to be
discrepant during the test and inspection
required by paragraph (f) of this AD,
accomplish the applicable actions specified
in paragraphs (g)(1) and (g)(2) of this AD at
the time specified, in accordance with Boeing
Special Attention Service Bulletin 737–57–
1289, dated June 13, 2007.
(1) Except as provided by paragraph (h) of
this AD: Do all applicable related
investigative and corrective actions
VerDate Aug<31>2005
14:13 Jul 07, 2008
Jkt 214001
(including detailed and general visual
inspections) before further flight, by doing all
the actions specified in the Accomplishment
Instructions of the service bulletin. Repeat
the inspections thereafter at intervals not to
exceed 1,000 flight cycles until the actions
required by paragraph (g)(2) of this AD have
been done. For any web panel with a material
thickness of less than 0.037 inch, replace the
web panel before further flight, in accordance
with paragraph 3.B.7. of the Accomplishment
Instructions of the service bulletin. Doing
this replacement ends the repetitive
inspections required by this paragraph.
(2) Except as required by paragraph (g)(1)
of this AD: Within 30 months or 6,000 flight
cycles after accomplishing the actions
required by paragraph (g)(1) of this AD,
whichever is later, replace the web panel in
accordance with the Accomplishment
Instructions of the service bulletin. Doing
this replacement ends the repetitive
inspections required by paragraph (g)(1) of
this AD.
Corrective Actions
(h) If any crack or corrosion is found
during any inspection required by paragraph
(g)(1) of this AD, and Boeing Special
Attention Service Bulletin 737–57–1289,
dated June 13, 2007, specifies to contact
Boeing for repair instructions: Before further
flight, repair according to a method approved
in accordance with the procedures specified
in paragraph (i) of this AD.
Alternative Methods of Compliance
(AMOCs)
(i)(1) The Manager, Seattle Aircraft
Certification Office (ACO), 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.
(3) 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
(j) You must use Boeing Special Attention
Service Bulletin 737–57–1289, dated June 13,
2007, to do the actions required by this AD,
unless the AD specifies otherwise.
(1) The Director of the Federal Register
approved the incorporation by reference of
this service information under 5 U.S.C.
552(a) and 1 CFR part 51.
(2) For service information identified in
this AD, contact Boeing Commercial
Airplanes, P.O. Box 3707, Seattle,
Washington 98124–2207.
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38887
(3) You may review copies of the service
information incorporated by reference 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, or go to: https://
www.archives.gov/federal_register/
code_of_federal_regulations/
ibr_locations.html.
Issued in Renton, Washington, on June 10,
2008.
Ali Bahrami,
Manager, Transport Airplane Directorate,
Aircraft Certification Service.
[FR Doc. E8–14475 Filed 7–7–08; 8:45 am]
BILLING CODE 4910–13–P
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA–2008–0409; Directorate
Identifier 2007–NM–265–AD; Amendment
39–15587; AD 2008–13–24]
RIN 2120–AA64
Airworthiness Directives; ATR Model
ATR42 Airplanes and Model ATR72–
101, –102, –201, –202, –211, and –212
Airplanes
Federal Aviation
Administration (FAA), Department of
Transportation (DOT).
ACTION: Final rule.
AGENCY:
SUMMARY: We are adopting a new
airworthiness directive (AD) for the
products listed above. This AD results
from mandatory continuing
airworthiness information (MCAI)
originated by an aviation authority of
another country to identify and correct
an unsafe condition on an aviation
product. The MCAI describes the unsafe
condition as:
It has been found on in-service aircraft that
some aileron tab bellcrank assemblies were
not in accordance with the definition
drawings.
The main item concerned is the retainer
Part Number S2711004620000, which has
been manufactured with a hole larger than it
should be, or redrilled out of limits.
The function of the retainer is to maintain
the spacer in position in case of rupture or
loss of the bolt which links the tab control
rod to the bellcrank assembly. If the diameter
of the retainer hole is out of limit, the
retainer function is lost and fail-safe
installation is no longer ensured. This
condition, if not corrected, could lead to loss
of the aileron tab bellcrank functionality,
resulting in diminished control of the
aircraft.
*
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08JYR1
*
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]]>Agencies
[Federal Register Volume 73, Number 131 (Tuesday, July 8, 2008)]
[Rules and Regulations]
[Pages 38885-38887]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: E8-14475]
-----------------------------------------------------------------------
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2007-0395; Directorate Identifier 2007-NM-157-AD;
Amendment 39-15588; AD 2008-13-25]
RIN 2120-AA64
Airworthiness Directives; Boeing Model 737-300 and -400 Series
Airplanes
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final rule.
-----------------------------------------------------------------------
SUMMARY: We are adopting a new airworthiness directive (AD) for certain
Boeing Model 737-300 and -400 series airplanes. This AD requires
testing and inspecting a certain web panel of the main wheel well
pressure deck to determine the material type and thickness; and related
investigative and corrective actions if necessary. This AD results from
several reports indicating that cracks ranging from 0.8 to 8.0 inches
long were found on a certain web panel of the main wheel well pressure
deck. We are issuing this AD to prevent fatigue cracking in the web
panel of the main wheel well pressure deck, which could result in
venting and consequent decompression of the airplane.
DATES: This AD is effective August 12, 2008.
The Director of the Federal Register approved the incorporation by
reference of a certain publication listed in this AD as of August 12,
2008.
ADDRESSES: For service information identified in this AD, contact
Boeing Commercial Airplanes, P.O. Box 3707, Seattle, Washington 98124-
2207.
Examining the AD Docket
You may examine the AD docket on the Internet at https://
www.regulations.gov; or in person at the Docket Management Facility
between 9 a.m. and 5 p.m., Monday through Friday, except Federal
holidays. The AD docket contains this AD, the regulatory evaluation,
any comments received, and other information. The address for the
Docket Office (telephone 800-647-5527) is the Document Management
Facility, U.S. Department of Transportation, Docket Operations, M-30,
West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue, SE.,
Washington, DC 20590.
FOR FURTHER INFORMATION CONTACT: Wayne Lockett, Aerospace Engineer,
Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office,
1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone (425)
917-6447; fax (425) 917-6590.
SUPPLEMENTARY INFORMATION:
Discussion
We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR
part 39 to include an airworthiness directive (AD) that would apply to
certain Boeing Model 737-300 and -400 series airplanes. That NPRM was
published in the Federal Register on January 10, 2008 (73 FR 1846).
That NPRM proposed to require testing and inspecting a certain web
panel of the main wheel well pressure deck to determine the material
type and thickness; and related investigative and corrective actions if
necessary.
Comments
We gave the public the opportunity to participate in developing
this AD. We considered the comments received.
Request To Change the Description of the Unsafe Condition
Boeing asks that the unsafe condition (end level effect) specified
in the applicable sections of the NPRM be changed from ``rapid
decompression'' to ``controlled decompression.'' Boeing states that the
most probable result of the cracking would be pressure loss or
controlled depressurization. Boeing has received reports of cracks
ranging from 4.5 to 8 inches in the web panel of the main wheel well
pressure deck; the reports included the following data:
Cabin crews reported a loud hissing noise coming from the
area below seats 14A, B, and C. No depressurization was reported.
The crew reported a loud hissing noise from the cabin
lining on the left-hand side at row 15. The cabin windows along the
left-hand side progressively frosted up until, after about 2 hours, all
the windows were frosted up between rows 11 through 17.
It was reported that it was not possible to pressurize
another airplane.
We partially agree with Boeing. We agree to change the end level
effect of the unsafe condition by removing the word ``rapid,'' since
Boeing has provided data verifying that the decompression does not
happen quickly. However, we do not agree that
[[Page 38886]]
the decompression is ``controlled'' because of the safety implications
and consequences associated with cracking on a web panel of the main
wheel well pressure deck. We have changed the applicable sections in
this AD accordingly.
Request To Clarify Certain Compliance Times
Boeing asks that we clarify the different compliance times for
replacing discrepant web panels, depending on the thickness, as
specified in Table 1 of Part 1.E., Compliance, of Boeing Special
Attention Service Bulletin 737-57-1289, dated June 13, 2007. (The
service bulletin was referenced in the NPRM as the appropriate source
of service information for accomplishing the specified actions.) Boeing
states that, as written, paragraphs (g)(1) and (g)(2) of the NPRM would
allow 30 months or 6,000 flight cycles, whichever is later, to replace
discrepant web panels. Boeing notes that this is acceptable for
discrepant web panels with a material thickness that is found to be
greater than or equal to 0.037 inch, and less than 0.047 inch; however,
for web panels with a material thickness of less than 0.037 inch the
specified compliance time is before further flight. Boeing adds that
web panels with a material thickness of less than 0.037 inch do not
meet the ultimate regulatory load requirements. Boeing also asks that
the related investigative and corrective actions be clarified.
We agree with Boeing that some clarification is necessary.
Paragraph (g)(1) of the AD requires accomplishing all applicable
related investigative and corrective actions before further flight
(which includes replacing any discrepant web panels) by doing all the
actions specified in the Accomplishment Instructions of the service
bulletin. The Accomplishment Instructions do not clearly identify web
panels with a material thickness of less than 0.037 inch; however, the
web panels are clearly identified in paragraph 1.E. of the service
bulletin. Paragraph 1.E. specifies replacing web panels with a material
thickness of less than 0.037 inch, as specified in paragraph 3.B.7. of
the Accomplishment Instructions of the service bulletin. Therefore, we
have clarified paragraph (g)(1) of this AD to add that the corrective
actions include replacing any web panel with a material thickness of
less than 0.037 inch before further flight. We have also changed
paragraph (g)(2) of this AD to clarify that the compliance time in that
paragraph is separate from the compliance time specified in paragraph
(g)(1). The related investigative and corrective actions are defined in
the service information section of the NPRM; therefore, no change is
necessary in this regard.
Request To Clarify That Additional Action Is Necessary
Boeing also asks that we change paragraph (e) of the NPRM to
clarify that additional action is necessary for operators that
inspected web panels using instructions that were contained in Boeing
Communication messages that were sent out on January 17, 2006, prior to
the release of the referenced service bulletin. Boeing states that the
messages were sent to airlines that were operating airplanes that could
have a discrepant web panel. Boeing adds that following release of
those messages, as part of the information being developed for release
in the referenced service bulletin, it was determined that additional
details were necessary to accurately define the instructions to inspect
for discrepant web panels. Boeing notes that the additional details,
which affect both the chemical spot test and the ultrasonic thickness
inspections, have been included in the service bulletin referenced in
the NPRM as the source of service information for doing the specified
actions; therefore, inspections accomplished without these additional
steps could result in incorrect identification of discrepant web
panels. Boeing also suggests that this language be added to paragraph
(e) of the AD.
We acknowledge Boeing's concerns; however, paragraph 1.E,
``Compliance,'' of the referenced service bulletin specifies that the
inspection instructions contained in the subject Boeing messages sent
out on January 17, 2006, did not include certain steps. That section
specifies that the chemical spot test and ultrasonic thickness
inspections must be done again by following the procedures in the
referenced service bulletin. In addition, paragraph (e) of this AD
states that if the actions required by this AD have been done
previously, they do not need to be done again. Therefore, we have made
no change to the AD in this regard.
Conclusion
We reviewed the relevant data, considered the comments received,
and determined that air safety and the public interest require adopting
the AD with the changes described previously. We also determined that
these changes will not increase the economic burden on any operator or
increase the scope of the AD.
Costs of Compliance
There are about 31 airplanes of the affected design in the
worldwide fleet. This AD affects 1 airplane of U.S. registry. The
required tests and inspections 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 AD for this U.S. operator is $240.
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
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.
You can find our regulatory evaluation and the estimated costs of
compliance in the AD Docket.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by
reference, Safety.
[[Page 38887]]
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 AD:
2008-13-25 Boeing: Amendment 39-15588. Docket No. FAA-2007-0395;
Directorate Identifier 2007-NM-157-AD.
Effective Date
(a) This airworthiness directive (AD) is effective August 12,
2008.
Affected ADs
(b) None.
Applicability
(c) This AD applies to Boeing Model 737-300 and -400 series
airplanes, certificated in any category; as identified in Boeing
Special Attention Service Bulletin 737-57-1289, dated June 13, 2007.
Unsafe Condition
(d) This AD results from several reports indicating that cracks
ranging from 0.8 to 8.0 inches long were found on a certain web
panel of the main wheel well pressure deck. We are issuing this AD
to prevent fatigue cracking in the web panel of the main wheel well
pressure deck, which could result in venting and consequent
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.
Testing/Inspecting/Investigative and Corrective Actions
(f) Within 6 months after the effective date of this AD: Do a
test of the web panel of the main wheel well pressure deck to
determine the material type, and do an ultrasonic inspection to
determine material thickness, by doing all the applicable actions
specified in the Accomplishment Instructions of Boeing Special
Attention Service Bulletin 737-57-1289, dated June 13, 2007.
(g) For airplanes on which the web thickness or material is
found to be discrepant during the test and inspection required by
paragraph (f) of this AD, accomplish the applicable actions
specified in paragraphs (g)(1) and (g)(2) of this AD at the time
specified, in accordance with Boeing Special Attention Service
Bulletin 737-57-1289, dated June 13, 2007.
(1) Except as provided by paragraph (h) of this AD: Do all
applicable related investigative and corrective actions (including
detailed and general visual inspections) before further flight, by
doing all the actions specified in the Accomplishment Instructions
of the service bulletin. Repeat the inspections thereafter at
intervals not to exceed 1,000 flight cycles until the actions
required by paragraph (g)(2) of this AD have been done. For any web
panel with a material thickness of less than 0.037 inch, replace the
web panel before further flight, in accordance with paragraph 3.B.7.
of the Accomplishment Instructions of the service bulletin. Doing
this replacement ends the repetitive inspections required by this
paragraph.
(2) Except as required by paragraph (g)(1) of this AD: Within 30
months or 6,000 flight cycles after accomplishing the actions
required by paragraph (g)(1) of this AD, whichever is later, replace
the web panel in accordance with the Accomplishment Instructions of
the service bulletin. Doing this replacement ends the repetitive
inspections required by paragraph (g)(1) of this AD.
Corrective Actions
(h) If any crack or corrosion is found during any inspection
required by paragraph (g)(1) of this AD, and Boeing Special
Attention Service Bulletin 737-57-1289, dated June 13, 2007,
specifies to contact Boeing for repair instructions: Before further
flight, repair according to a method approved in accordance with the
procedures specified in paragraph (i) of this AD.
Alternative Methods of Compliance (AMOCs)
(i)(1) The Manager, Seattle Aircraft Certification Office (ACO),
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.
(3) 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
(j) You must use Boeing Special Attention Service Bulletin 737-
57-1289, dated June 13, 2007, to do the actions required by this AD,
unless the AD specifies otherwise.
(1) The Director of the Federal Register approved the
incorporation by reference of this service information under 5
U.S.C. 552(a) and 1 CFR part 51.
(2) For service information identified in this AD, contact
Boeing Commercial Airplanes, P.O. Box 3707, Seattle, Washington
98124-2207.
(3) You may review copies of the service information
incorporated by reference 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, or
go to: https://www.archives.gov/federal_register/code_of_federal_
regulations/ibr_locations.html.
Issued in Renton, Washington, on June 10, 2008.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. E8-14475 Filed 7-7-08; 8:45 am]
BILLING CODE 4910-13-P
