Airworthiness Directives; Boeing Model 747 Airplanes, 62904-62906 [E6-17941]
Download as PDF
62904
Federal Register / Vol. 71, No. 208 / Friday, October 27, 2006 / Rules and Regulations
January 2005, 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 EADS SOCATA, Direction
des Services, 65921 Tarbes Cedex 9, France;
telephone: 33 (0)5 62.41.73.00; fax: 33 (0)5
62.41.76.54; or SOCATA Aircraft, INC., North
Perry Airport, 7501 Airport Road, Pembroke
Pines, Florida 33023; telephone: (954) 893–
1400; fax: (954) 964–4141.
(3) You may review copies at the FAA,
Central Region, Office of the Regional
Counsel, 901 Locust, Room 506, Kansas City,
Missouri 64106; 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/
cfr/ibr-locations.html.
Issued in Kansas City, Missouri, on
October 19, 2006.
James E. Jackson,
Acting Manager, Small Airplane Directorate,
Aircraft Certification Service.
[FR Doc. E6–17930 Filed 10–26–06; 8:45 am]
BILLING CODE 4910–13–P
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA–2006–24119; Directorate
Identifier 2005–NM–100–AD; Amendment
39–14806; AD 2006–22–09]
RIN 2120–AA64
Airworthiness Directives; Boeing
Model 747 Airplanes
Federal Aviation
Administration (FAA), Department of
Transportation (DOT).
ACTION: Final rule.
rmajette on PROD1PC67 with RULES1
AGENCY:
SUMMARY: The FAA is adopting a new
airworthiness directive (AD) for certain
Boeing Model 747 airplanes. This AD
requires repetitive mid- and lowfrequency eddy current inspections for
cracks in the overlapped skin panels in
the fuselage skin lap joints in sections
41, 42, 44, and 46, and corrective
actions if necessary. This AD results
from a report indicating that an operator
found multiple small cracks in the
overlapped skin panels in the fuselage
skin lap joints. We are issuing this AD
to detect and correct cracks in the
overlapped skin panels, which could
join together and result in reduced
structural capability in the skin and
consequent rapid decompression of the
airplane.
DATES: This AD becomes effective
December 1, 2006.
VerDate Aug<31>2005
14:48 Oct 26, 2006
Jkt 211001
The Director of the Federal Register
approved the incorporation by reference
of a certain publication listed in the AD
as of December 1, 2006.
ADDRESSES: You may examine the AD
docket on the Internet at https://
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: Ivan
Li, Aerospace Engineer, Airframe
Branch, ANM–120S, FAA, Seattle
Aircraft Certification Office, 1601 Lind
Avenue, SW., Renton, Washington
98057–3356; telephone (425) 917–6437;
fax (425) 917–6590.
SUPPLEMENTARY INFORMATION:
Examining the Docket
You may examine the airworthiness
directive (AD) docket on the Internet at
https://dms.dot.gov or in person at the
Docket Management Facility office
between 9 a.m. and 5 p.m., Monday
through Friday, except Federal holidays.
The Docket Management Facility office
(telephone (800) 647–5227) is located on
the plaza level of the Nassif Building at
the street address stated in the
ADDRESSES section.
Discussion
The FAA issued a notice of proposed
rulemaking (NPRM) to amend 14 CFR
part 39 to include an AD that would
apply to certain Boeing Model 747
airplanes. That NPRM was published in
the Federal Register on March 14, 2006
(71 FR 13055). That NPRM proposed to
require repetitive mid- and lowfrequency eddy current inspections for
cracks in the overlapped skin panels in
the fuselage skin lap joints in sections
41, 42, 44, and 46, and corrective
actions if necessary.
Comments
We provided the public the
opportunity to participate in the
development of this AD. We have
considered the comments received.
Support for the NPRM
Boeing supports the NPRM as
proposed.
Request To Delay Final Rule Pending
New Service Information
Japan Airlines (JAL) states that Boeing
Alert Service Bulletin 747–53A2501,
dated March 24, 2005, which was
referenced as the appropriate source of
service information for accomplishing
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Fmt 4700
Sfmt 4700
the actions proposed in the NPRM,
contains various errors and omissions.
For example, the alert service bulletin
does not have inspection procedures for
certain internal structural details that
cover the lap, and there is no inspection
procedure specific to the Boeing Model
747–400 converted freighter. JAL would
like us to delay issuing the final rule
until Boeing has revised the alert service
bulletin.
We partially agree with JAL. We agree
that there are details and configurations
that could be changed in future
revisions of the alert service bulletin.
The issues JAL mentions would require
an alternative method of compliance
(AMOC) to the inspection instructions
as given in the original issue of the alert
service bulletin. Operators may request
an AMOC in accordance with the
procedures in paragraph (j) of the final
rule. We disagree that we should delay
the final rule until Boeing revises the
alert service bulletin. We have
identified an unsafe condition, and
delaying issuance of the final rule until
Boeing revises its service information
would result in an unwarranted delay of
the inspections that are intended to
address that unsafe condition. We have
not changed the final rule in this regard.
Request To Revise Inspection
Threshold
Air Transport Association (ATA), on
behalf of its member Northwest Airlines
(NWA), requests that we allow the
initial inspection to occur within 3,000
flight cycles after the most recent
Supplemental Structural Inspection
Document (SSID) inspection for items
F–25K, F–25L, and F–25M in Boeing
SSID D6–35022.
We disagree with the commenters.
The SSID program is an exploratory
inspection program. The inspection
intervals in the SSID were derived from
required damage tolerance ratings
(DTRs) that were based on ‘‘fleet crack’’
criteria. This means that at the time the
DTRs were developed, there was no
known cracking in the area; therefore,
the required DTRs could remain at a
lower level until cracking was
discovered. However, operators
subsequently found cracking in certain
lap joint lower skins, and Boeing issued
Alert Service Bulletin 747–53A2501 to
detect and correct this cracking. The
required DTRs that drive the thresholds
and intervals were developed using
‘‘first crack’’ criteria, which is higher
than ‘‘fleet crack’’ criteria. ‘‘First crack’’
criteria must detect cracking that is
known to have occurred on other
airplanes and, therefore, cannot rely on
a worldwide fleet of airplanes as a
statistical sample group.
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Federal Register / Vol. 71, No. 208 / Friday, October 27, 2006 / Rules and Regulations
The inspection specified in Boeing
Alert Service Bulletin 747–53A2501 is
an internal medium frequency eddy
current (MFEC) inspection, which is
able to detect a crack size smaller than
that detectable by the external low
frequency eddy current (LFEC)
inspection required by the SSID
program. Both inspection techniques are
used to detect cracks on the outer
surface of the lower skin panel at the
lower row of fasteners of the lap splice.
However, the LFEC inspection looks
through the upper skin panel; the MFEC
technique uses a probe that is in direct
contact with the lower skin panel on the
inner surface. Therefore, a 3,000-flightcycle repetitive interval using an LFEC
method does not provide the same level
of certainty as a 3,000-flight-cycle
repetitive inspection using the MFEC
method.
We have not changed the final rule in
this regard.
Request To Change Costs of Compliance
ATA, on behalf of NWA, also requests
that we change the costs of compliance.
NWA states that it has determined that
approximately 120 work hours would be
required to accomplish the nondestructive test procedures specified in
Boeing Alert Service Bulletin 747–
53A2501. The NPRM gives a cost
estimate of 68 hours to do this task.
NWA states that it is worth noting that
if the inspection has to be performed
independent of other major fuselage
internal inspections, then over 1,000
additional hours of access and
restoration labor will be required. NWA
states that this scenario is likely if the
initial inspection is required
independent of the SSID or fuselage
fatigue inspection programs. The 1,000flight-cycle initial inspection threshold
could prompt such a scenario.
We disagree with the request to
change the costs of compliance. The 68
work-hour estimate represents the time
necessary to perform only the action
actually required by the AD. The action
in the NPRM reflects only the direct
costs of the specific required action
(inspection) based on the best available
data from the manufacturer. The cost
analysis in AD rulemaking actions
typically does not include incidental
costs such as the time required to gain
access and close up, time necessary for
planning, or time necessary for other
administrative tasks. Those incidental
costs, which may vary significantly
among operators, are almost impossible
to calculate. We have not changed the
final rule in this regard.
Request To Revise Compliance Time
ATA also recommends that we align
the compliance period for the nondestructive test procedures specified in
Boeing Alert Service Bulletin 747–
53A2501, with scheduled maintenance
intervals in order to avoid the order-ofmagnitude increase in the effect of the
proposed actions if they must be
accomplished on an unscheduled basis.
62905
We disagree with the request to revise
the compliance time. We acknowledge
that for certain airplanes the inspections
may have to be performed independent
of the SSID or fuselage fatigue
inspection programs. In developing an
appropriate compliance time for this
action, including the 1,000-flight-cycle
initial inspection threshold, we
considered the urgency associated with
the subject unsafe condition, the
manufacturer’s recommendations, and
the practical aspect of accomplishing
the required inspections within a period
of time that corresponds to the normal
scheduled maintenance for most
affected operators. We have not changed
the final rule in this regard. However,
according to the provisions of paragraph
(j) of the final rule, we may approve
requests to adjust the compliance time
if the request includes data that prove
that the new compliance time would
provide an acceptable level of safety.
Conclusion
We have carefully reviewed the
available data, including the comments
received, and determined that air safety
and the public interest require adopting
the AD as proposed.
Costs of Compliance
There are about 1,081 airplanes of the
affected design in the worldwide fleet.
The following table provides the
estimated costs for U.S. operators to
comply with this AD.
ESTIMATED COSTS
Action
Work hours
Inspection for Model 747SP
series airplanes.
Inspection for all other Model
747 series airplanes.
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Number of
U.S.-registered
airplanes
$80
$3,840, per inspection cycle
10
68
80
$5,440, per inspection cycle
196
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
14:48 Oct 26, 2006
Cost per airplane
48
Authority For this Rulemaking
VerDate Aug<31>2005
Average labor
rate per hour
Jkt 211001
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.
PO 00000
Frm 00031
Fmt 4700
Sfmt 4700
Fleet cost
$38,400, per inspection
cycle.
$1,066,240, per inspection
cycle.
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.
E:\FR\FM\27OCR1.SGM
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62906
Federal Register / Vol. 71, No. 208 / Friday, October 27, 2006 / Rules and Regulations
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation
safety, Incorporation by reference,
Safety.
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 Federal Aviation
Administration (FAA) amends § 39.13
by adding the following new
airworthiness directive (AD):
2006–22–09 Boeing: Amendment 39–14806.
Docket No. FAA–2006–24119;
Directorate Identifier 2005–NM–100–AD.
Effective Date
(a) This AD becomes effective December 1,
2006.
Affected ADs
(b) 2004–13–02.
Applicability
(c) This AD applies to Boeing Model 747–
100, 747–100B, 747–100B SUD, 747–200B,
747–200C, 747–200F, 747–300, 747–400,
747–400D, 747–400F, 747SR, and 747SP
series airplanes, certificated in any category;
as identified in Boeing Alert Service Bulletin
747–53A2501, dated March 24, 2005.
Unsafe Condition
(d) This AD results from a report indicating
that an operator found multiple small cracks
in the overlapped skin panels in the fuselage
skin lap joints. We are issuing this AD to
detect and correct cracks in the overlapped
skin panels, which could join together and
result in reduced structural capability in the
skin and consequent rapid decompression of
the airplane.
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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.
Inspections and Corrective Actions: For
Airplanes With Line Numbers 1 Through
200 Inclusive
(f) For airplanes with line numbers 1
through 200 inclusive, at the applicable time
in paragraph (f)(1) or (f)(2) of this AD: Do the
applicable eddy current inspection or
inspections for cracks in the overlapped skin
panels in the fuselage skin lap joints in
sections 41, 42, 44, and 46; and do all
applicable corrective actions before further
flight. Except as provided by paragraph
(f)(1)(ii) of this AD, repeat the applicable
inspection or inspections thereafter at
VerDate Aug<31>2005
14:48 Oct 26, 2006
Jkt 211001
intervals not to exceed 3,000 flight cycles.
Except as provided by paragraph (h) of this
AD, do all actions in accordance with the
Accomplishment Instructions of Boeing Alert
Service Bulletin 747–53A2501, dated March
24, 2005.
(1) Except as provided by paragraph (f)(2)
of this AD, do the applicable action in
paragraph (f)(1)(i) or (f)(1)(ii) of this AD.
(i) For airplanes that have accumulated
fewer than 29,000 total flight cycles as of the
effective date of this AD: Before the
accumulation of 25,000 total flight cycles, or
within 1,000 flight cycles after the effective
date of this AD, whichever occurs later, do
a mid-frequency eddy current inspection for
cracks of the internal surface at the
overlapped skin around the bottom row of
fasteners in the lap joint.
(ii) For airplanes that have accumulated
29,000 or more total flight cycles, do the
inspections in accordance with the
requirements of AD 2004–13–02, amendment
39–13682, at the applicable threshold and
intervals in that AD. Doing the repeat
inspections in accordance with AD 2004–13–
02, terminates the repetitive inspection
requirements of this AD only for airplanes
with line numbers 1 through 200 inclusive.
(2) For airplanes that have had overlapped
skin panels replaced: Do the eddy current
inspections of the replaced overlapped panel
prior to the accumulation of 25,000 total
flight cycles since panel replacement, or
within 1,000 flight cycles after the effective
date of this AD, whichever occurs later. Skin
panel replacement, along with ongoing
inspections in accordance with paragraph (f)
of this AD, terminates the requirements of
paragraphs (a) and (d) of AD 2004–13–02,
only for the skin lap sections where the
overlapped panel has been replaced.
Inspections and Corrective Actions: For
Airplanes With Line Numbers 201 and
Subsequent
(g) For airplanes with line numbers 201
and subsequent: Before the accumulation of
25,000 total flight cycles, within 1,000 flight
cycles after the effective date of this AD, or
within 25,000 flight cycles after the time
when the overlapped skin was replaced,
whichever occurs later, do the applicable
inspection in paragraphs (g)(1) and (g)(2) of
this AD for cracks in the overlapped skin
panels in the fuselage skin lap joints in
sections 41, 42, 44, and 46; and do all
applicable corrective actions before further
flight. Repeat the applicable inspection
thereafter at intervals not to exceed 3,000
flight cycles. Except as provided by
paragraph (h) of this AD, do all actions in
accordance with the Accomplishment
Instructions of Boeing Alert Service Bulletin
747–53A2501, dated March 24, 2005.
(1) Do a mid-frequency eddy current
inspection for cracks of the internal surface
at the overlapped skin around the bottom
row of fasteners in the lap joint.
(2) Do a low-frequency eddy current
inspection for cracks of the overlapped skin
around the bottom row of fasteners at the
section 41 lap joints with four rows of
fasteners.
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Frm 00032
Fmt 4700
Sfmt 4700
Repair Instructions
(h) If any crack is found during any
inspection required by this AD, and Boeing
Alert Service Bulletin 747–53A2501, dated
March 24, 2005, specifies to contact Boeing
for appropriate action: Before further flight,
repair the crack using a method approved in
accordance with the procedures specified in
paragraph (j) of this AD.
No Reporting Required
(i) Although Boeing Alert Service Bulletin
747–53A2501, dated March 24, 2005,
specifies to submit certain information to the
manufacturer, this AD does not include that
requirement.
Alternative Methods of Compliance
(AMOCs)
(j)(1) The Manager, Seattle Aircraft
Certification Office (ACO), FAA, has the
authority to approve AMOCs for this AD, if
requested in accordance with the procedures
found in 14 CFR 39.19.
(2) An AMOC that provides an acceptable
level of safety may be used for any repair
required by this AD, if it is approved by an
Authorized Representative for the Boeing
Commercial 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.
(3) Before using any AMOC approved in
accordance with § 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
(k) You must use Boeing Alert Service
Bulletin 747–53A2501, dated March 24,
2005, 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 this document 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 https://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 https://
www.archives.gov/federal_register/code_of
_federal _regulations/ibr_locations.html.
Issued in Renton, Washington, on October
18, 2006.
Jeffrey E. Duven,
Acting Manager, Transport Airplane
Directorate, Aircraft Certification Service.
[FR Doc. E6–17941 Filed 10–26–06; 8:45 am]
BILLING CODE 4910–13–P
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Agencies
[Federal Register Volume 71, Number 208 (Friday, October 27, 2006)]
[Rules and Regulations]
[Pages 62904-62906]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: E6-17941]
-----------------------------------------------------------------------
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2006-24119; Directorate Identifier 2005-NM-100-AD;
Amendment 39-14806; AD 2006-22-09]
RIN 2120-AA64
Airworthiness Directives; Boeing Model 747 Airplanes
AGENCY: Federal Aviation Administration (FAA), Department of
Transportation (DOT).
ACTION: Final rule.
-----------------------------------------------------------------------
SUMMARY: The FAA is adopting a new airworthiness directive (AD) for
certain Boeing Model 747 airplanes. This AD requires repetitive mid-
and low-frequency eddy current inspections for cracks in the overlapped
skin panels in the fuselage skin lap joints in sections 41, 42, 44, and
46, and corrective actions if necessary. This AD results from a report
indicating that an operator found multiple small cracks in the
overlapped skin panels in the fuselage skin lap joints. We are issuing
this AD to detect and correct cracks in the overlapped skin panels,
which could join together and result in reduced structural capability
in the skin and consequent rapid decompression of the airplane.
DATES: This AD becomes effective December 1, 2006.
The Director of the Federal Register approved the incorporation by
reference of a certain publication listed in the AD as of December 1,
2006.
ADDRESSES: You may examine the AD docket on the Internet at https://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: Ivan Li, Aerospace Engineer, Airframe
Branch, ANM-120S, FAA, Seattle Aircraft Certification Office, 1601 Lind
Avenue, SW., Renton, Washington 98057-3356; telephone (425) 917-6437;
fax (425) 917-6590.
SUPPLEMENTARY INFORMATION:
Examining the Docket
You may examine the airworthiness directive (AD) docket on the
Internet at https://dms.dot.gov or in person at the Docket Management
Facility office between 9 a.m. and 5 p.m., Monday through Friday,
except Federal holidays. The Docket Management Facility office
(telephone (800) 647-5227) is located on the plaza level of the Nassif
Building at the street address stated in the ADDRESSES section.
Discussion
The FAA issued a notice of proposed rulemaking (NPRM) to amend 14
CFR part 39 to include an AD that would apply to certain Boeing Model
747 airplanes. That NPRM was published in the Federal Register on March
14, 2006 (71 FR 13055). That NPRM proposed to require repetitive mid-
and low-frequency eddy current inspections for cracks in the overlapped
skin panels in the fuselage skin lap joints in sections 41, 42, 44, and
46, and corrective actions if necessary.
Comments
We provided the public the opportunity to participate in the
development of this AD. We have considered the comments received.
Support for the NPRM
Boeing supports the NPRM as proposed.
Request To Delay Final Rule Pending New Service Information
Japan Airlines (JAL) states that Boeing Alert Service Bulletin 747-
53A2501, dated March 24, 2005, which was referenced as the appropriate
source of service information for accomplishing the actions proposed in
the NPRM, contains various errors and omissions. For example, the alert
service bulletin does not have inspection procedures for certain
internal structural details that cover the lap, and there is no
inspection procedure specific to the Boeing Model 747-400 converted
freighter. JAL would like us to delay issuing the final rule until
Boeing has revised the alert service bulletin.
We partially agree with JAL. We agree that there are details and
configurations that could be changed in future revisions of the alert
service bulletin. The issues JAL mentions would require an alternative
method of compliance (AMOC) to the inspection instructions as given in
the original issue of the alert service bulletin. Operators may request
an AMOC in accordance with the procedures in paragraph (j) of the final
rule. We disagree that we should delay the final rule until Boeing
revises the alert service bulletin. We have identified an unsafe
condition, and delaying issuance of the final rule until Boeing revises
its service information would result in an unwarranted delay of the
inspections that are intended to address that unsafe condition. We have
not changed the final rule in this regard.
Request To Revise Inspection Threshold
Air Transport Association (ATA), on behalf of its member Northwest
Airlines (NWA), requests that we allow the initial inspection to occur
within 3,000 flight cycles after the most recent Supplemental
Structural Inspection Document (SSID) inspection for items F-25K, F-
25L, and F-25M in Boeing SSID D6-35022.
We disagree with the commenters. The SSID program is an exploratory
inspection program. The inspection intervals in the SSID were derived
from required damage tolerance ratings (DTRs) that were based on
``fleet crack'' criteria. This means that at the time the DTRs were
developed, there was no known cracking in the area; therefore, the
required DTRs could remain at a lower level until cracking was
discovered. However, operators subsequently found cracking in certain
lap joint lower skins, and Boeing issued Alert Service Bulletin 747-
53A2501 to detect and correct this cracking. The required DTRs that
drive the thresholds and intervals were developed using ``first crack''
criteria, which is higher than ``fleet crack'' criteria. ``First
crack'' criteria must detect cracking that is known to have occurred on
other airplanes and, therefore, cannot rely on a worldwide fleet of
airplanes as a statistical sample group.
[[Page 62905]]
The inspection specified in Boeing Alert Service Bulletin 747-
53A2501 is an internal medium frequency eddy current (MFEC) inspection,
which is able to detect a crack size smaller than that detectable by
the external low frequency eddy current (LFEC) inspection required by
the SSID program. Both inspection techniques are used to detect cracks
on the outer surface of the lower skin panel at the lower row of
fasteners of the lap splice. However, the LFEC inspection looks through
the upper skin panel; the MFEC technique uses a probe that is in direct
contact with the lower skin panel on the inner surface. Therefore, a
3,000-flight-cycle repetitive interval using an LFEC method does not
provide the same level of certainty as a 3,000-flight-cycle repetitive
inspection using the MFEC method.
We have not changed the final rule in this regard.
Request To Change Costs of Compliance
ATA, on behalf of NWA, also requests that we change the costs of
compliance. NWA states that it has determined that approximately 120
work hours would be required to accomplish the non-destructive test
procedures specified in Boeing Alert Service Bulletin 747-53A2501. The
NPRM gives a cost estimate of 68 hours to do this task. NWA states that
it is worth noting that if the inspection has to be performed
independent of other major fuselage internal inspections, then over
1,000 additional hours of access and restoration labor will be
required. NWA states that this scenario is likely if the initial
inspection is required independent of the SSID or fuselage fatigue
inspection programs. The 1,000-flight-cycle initial inspection
threshold could prompt such a scenario.
We disagree with the request to change the costs of compliance. The
68 work-hour estimate represents the time necessary to perform only the
action actually required by the AD. The action in the NPRM reflects
only the direct costs of the specific required action (inspection)
based on the best available data from the manufacturer. The cost
analysis in AD rulemaking actions typically does not include incidental
costs such as the time required to gain access and close up, time
necessary for planning, or time necessary for other administrative
tasks. Those incidental costs, which may vary significantly among
operators, are almost impossible to calculate. We have not changed the
final rule in this regard.
Request To Revise Compliance Time
ATA also recommends that we align the compliance period for the
non-destructive test procedures specified in Boeing Alert Service
Bulletin 747-53A2501, with scheduled maintenance intervals in order to
avoid the order-of-magnitude increase in the effect of the proposed
actions if they must be accomplished on an unscheduled basis.
We disagree with the request to revise the compliance time. We
acknowledge that for certain airplanes the inspections may have to be
performed independent of the SSID or fuselage fatigue inspection
programs. In developing an appropriate compliance time for this action,
including the 1,000-flight-cycle initial inspection threshold, we
considered the urgency associated with the subject unsafe condition,
the manufacturer's recommendations, and the practical aspect of
accomplishing the required inspections within a period of time that
corresponds to the normal scheduled maintenance for most affected
operators. We have not changed the final rule in this regard. However,
according to the provisions of paragraph (j) of the final rule, we may
approve requests to adjust the compliance time if the request includes
data that prove that the new compliance time would provide an
acceptable level of safety.
Conclusion
We have carefully reviewed the available data, including the
comments received, and determined that air safety and the public
interest require adopting the AD as proposed.
Costs of Compliance
There are about 1,081 airplanes of the affected design in the
worldwide fleet. The following table provides the estimated costs for
U.S. operators to comply with this AD.
Estimated Costs
----------------------------------------------------------------------------------------------------------------
Number of U.S.-
Action Work hours Average labor Cost per registered Fleet cost
rate per hour airplane airplanes
----------------------------------------------------------------------------------------------------------------
Inspection for Model 747SP 48 $80 $3,840, per 10 $38,400, per
series airplanes. inspection inspection
cycle. cycle.
Inspection for all other 68 80 $5,440, per 196 $1,066,240, per
Model 747 series airplanes. inspection inspection
cycle. 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.
[[Page 62906]]
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]
2. The Federal Aviation Administration (FAA) amends Sec. 39.13 by
adding the following new airworthiness directive (AD):
2006-22-09 Boeing: Amendment 39-14806. Docket No. FAA-2006-24119;
Directorate Identifier 2005-NM-100-AD.
Effective Date
(a) This AD becomes effective December 1, 2006.
Affected ADs
(b) 2004-13-02.
Applicability
(c) This AD applies to Boeing Model 747-100, 747-100B, 747-100B
SUD, 747-200B, 747-200C, 747-200F, 747-300, 747-400, 747-400D, 747-
400F, 747SR, and 747SP series airplanes, certificated in any
category; as identified in Boeing Alert Service Bulletin 747-
53A2501, dated March 24, 2005.
Unsafe Condition
(d) This AD results from a report indicating that an operator
found multiple small cracks in the overlapped skin panels in the
fuselage skin lap joints. We are issuing this AD to detect and
correct cracks in the overlapped skin panels, which could join
together and result in reduced structural capability in the skin 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.
Inspections and Corrective Actions: For Airplanes With Line Numbers 1
Through 200 Inclusive
(f) For airplanes with line numbers 1 through 200 inclusive, at
the applicable time in paragraph (f)(1) or (f)(2) of this AD: Do the
applicable eddy current inspection or inspections for cracks in the
overlapped skin panels in the fuselage skin lap joints in sections
41, 42, 44, and 46; and do all applicable corrective actions before
further flight. Except as provided by paragraph (f)(1)(ii) of this
AD, repeat the applicable inspection or inspections thereafter at
intervals not to exceed 3,000 flight cycles. Except as provided by
paragraph (h) of this AD, do all actions in accordance with the
Accomplishment Instructions of Boeing Alert Service Bulletin 747-
53A2501, dated March 24, 2005.
(1) Except as provided by paragraph (f)(2) of this AD, do the
applicable action in paragraph (f)(1)(i) or (f)(1)(ii) of this AD.
(i) For airplanes that have accumulated fewer than 29,000 total
flight cycles as of the effective date of this AD: Before the
accumulation of 25,000 total flight cycles, or within 1,000 flight
cycles after the effective date of this AD, whichever occurs later,
do a mid-frequency eddy current inspection for cracks of the
internal surface at the overlapped skin around the bottom row of
fasteners in the lap joint.
(ii) For airplanes that have accumulated 29,000 or more total
flight cycles, do the inspections in accordance with the
requirements of AD 2004-13-02, amendment 39-13682, at the applicable
threshold and intervals in that AD. Doing the repeat inspections in
accordance with AD 2004-13-02, terminates the repetitive inspection
requirements of this AD only for airplanes with line numbers 1
through 200 inclusive.
(2) For airplanes that have had overlapped skin panels replaced:
Do the eddy current inspections of the replaced overlapped panel
prior to the accumulation of 25,000 total flight cycles since panel
replacement, or within 1,000 flight cycles after the effective date
of this AD, whichever occurs later. Skin panel replacement, along
with ongoing inspections in accordance with paragraph (f) of this
AD, terminates the requirements of paragraphs (a) and (d) of AD
2004-13-02, only for the skin lap sections where the overlapped
panel has been replaced.
Inspections and Corrective Actions: For Airplanes With Line Numbers 201
and Subsequent
(g) For airplanes with line numbers 201 and subsequent: Before
the accumulation of 25,000 total flight cycles, within 1,000 flight
cycles after the effective date of this AD, or within 25,000 flight
cycles after the time when the overlapped skin was replaced,
whichever occurs later, do the applicable inspection in paragraphs
(g)(1) and (g)(2) of this AD for cracks in the overlapped skin
panels in the fuselage skin lap joints in sections 41, 42, 44, and
46; and do all applicable corrective actions before further flight.
Repeat the applicable inspection thereafter at intervals not to
exceed 3,000 flight cycles. Except as provided by paragraph (h) of
this AD, do all actions in accordance with the Accomplishment
Instructions of Boeing Alert Service Bulletin 747-53A2501, dated
March 24, 2005.
(1) Do a mid-frequency eddy current inspection for cracks of the
internal surface at the overlapped skin around the bottom row of
fasteners in the lap joint.
(2) Do a low-frequency eddy current inspection for cracks of the
overlapped skin around the bottom row of fasteners at the section 41
lap joints with four rows of fasteners.
Repair Instructions
(h) If any crack is found during any inspection required by this
AD, and Boeing Alert Service Bulletin 747-53A2501, dated March 24,
2005, specifies to contact Boeing for appropriate action: Before
further flight, repair the crack using a method approved in
accordance with the procedures specified in paragraph (j) of this
AD.
No Reporting Required
(i) Although Boeing Alert Service Bulletin 747-53A2501, dated
March 24, 2005, specifies to submit certain information to the
manufacturer, this AD does not include that requirement.
Alternative Methods of Compliance (AMOCs)
(j)(1) The Manager, Seattle Aircraft Certification Office (ACO),
FAA, has the authority to approve AMOCs for this AD, if requested in
accordance with the procedures found in 14 CFR 39.19.
(2) An AMOC that provides an acceptable level of safety may be
used for any repair required by this AD, if it is approved by an
Authorized Representative for the Boeing Commercial 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.
(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
(k) You must use Boeing Alert Service Bulletin 747-53A2501,
dated March 24, 2005, 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 this
document 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 https://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 https://www.archives.gov/federal_register/code_of --federal --regulations/ibr--locations.html.
Issued in Renton, Washington, on October 18, 2006.
Jeffrey E. Duven,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. E6-17941 Filed 10-26-06; 8:45 am]
BILLING CODE 4910-13-P