[Federal Register: August 20, 2003 (Volume 68, Number 161)]
[Rules and Regulations]
[Page 50061-50064]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr20au03-8]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 2001-NM-178-AD; Amendment 39-13280; AD 2003-17-06]
RIN 2120-AA64
Airworthiness Directives; Boeing Model 747-100, 747SP, and 747SR
Series Airplanes
AGENCY: Federal Aviation Administration, DOT.
ACTION: Final rule.
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SUMMARY: This amendment adopts a new airworthiness directive (AD),
applicable to certain Boeing Model 747-100, 747SP, and 747SR series
airplanes, that requires repetitive inspections to find fatigue
cracking between the seal ribs of the front spar web of the wing and
outboard of the outboard seal rib to front spar station inboard (FSSI)
711, and repair of cracked structure. This AD also provides for an
optional modification of a certain area. This action is necessary to
find and fix fatigue cracking between the seal ribs of the front spar
web of the wing and outboard of the outboard seal rib to FSSI 711,
which could result in fuel leakage into the area of the inboard
engines, and consequent increased risk of a fire. This action is
intended to address the identified unsafe condition.
DATES: Effective September 24, 2003.
The incorporation by reference of certain publications listed in
the regulations is approved by the Director of the Federal Register as
of September 24, 2003.
ADDRESSES: The service information referenced in this AD may be
obtained from Boeing Commercial Airplane Group, P.O. Box 3707, Seattle,
Washington 98124-2207. This information may be examined at the Federal
Aviation Administration (FAA), Transport Airplane Directorate, Rules
Docket, 1601 Lind Avenue, SW., Renton, Washington; or at the Office of
the Federal Register, 800 North Capitol Street, NW., suite 700,
Washington, DC.
FOR FURTHER INFORMATION CONTACT: Tamara L. Anderson, Aerospace
Engineer, Airframe Branch, ANM-120S, FAA, Transport Airplane
Directorate, Seattle Aircraft Certification Office, 1601 Lind Avenue,
SW., Renton, Washington 98055-4056; telephone (425) 917-6421; fax (425)
917-6590.
SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal
Aviation Regulations (14 CFR part 39) to include an airworthiness
directive (AD) that is applicable to certain Boeing Model 747-100,
747SP, and 747SR series airplanes, was published in the Federal
Register on February 4, 2003 (68 FR 5610). That action proposed to
require repetitive inspections to find fatigue cracking between the
seal ribs of the front spar web of the wing, and repair of cracked
structure. That action also proposed to provide for an optional
modification of a certain area.
Comments
Interested persons have been afforded an opportunity to participate
in the making of this amendment. The FAA has given due consideration to
the comments received from a single commenter.
Request To Revise Compliance Time
The commenter requests that we revise compliance time information
in paragraphs (a) and (b) of the proposed AD to make the wording of the
inspection threshold and grace period more specific. The commenter
specifically asks that we add a new paragraph (a)(2) and revise
paragraph (b)(1) of the proposed AD to include the words ``Within 18
months of the effective date of this AD for all airplanes that have
exceeded the total flight cycles or total flight hours * * *.'' The
commenter states that this change is necessary so that operators of
airplanes that have exceeded the thresholds specified in the service
bulletin will know how much time they have to accomplish the initial
inspection.
We do not concur with the commenter's request. Paragraph (b)(1) of
this AD specifically refers to Tables 1 through 3 of Figure 1 of the
Accomplishment Instructions or Appendix A of the referenced service
bulletin as the appropriate source of the compliance time for the
applicable initial or post-modification inspection. Paragraph (a) of
this AD is intended to clarify the grace period stated in the service
bulletin. We find that affected operators should be readily able to
determine the applicable compliance time, as clarified by paragraph (a)
of this AD. No change is necessary in this regard.
Request To Clarify Repair Instructions
The commenter requests that we revise paragraph (c) of the proposed
AD to add a reference to corrosion or damage that may be found during
the inspections or the optional modification specified in paragraph (d)
of the proposed AD. The commenter states
[[Page 50062]]
that operators may find corrosion or damage during the required
inspections, or fastener holes may be damaged during accomplishment of
the optional modification.
We do not concur with the commenter's request to add a reference to
corrosion or damage. The inspections described in the referenced
service bulletin and required by this AD are intended only to reveal
cracking related to the identified unsafe condition. If any corrosion
or damage is found during accomplishment of an action required by this
AD, an operator would be required--regardless of AD direction--to
correct the corrosion or damage to ensure that the airplane is operated
in an airworthy condition as required by the Federal Aviation
Regulations.
Related to this, we infer that the rationale for the commenter's
request is to ensure that repairs of corrosion and other damage may be
approved by a delegated Designated Engineering Representative (DER). We
do not agree that any change is necessary to meet the commenter's
intent. If corrosion or damage is found, and the Manager of the Seattle
Aircraft Certification Office (ACO) has authorized a Boeing Company DER
to approve an alternative method of compliance for this AD, then the
Boeing Company DER may approve a repair if it is structurally adequate
per the FAA's delegation letter.
We concur, however, with the commenter's request to revise
paragraph (c) of this final rule to add a reference to the optional
modification. We note that paragraph (c) of the proposed AD states that
it applies to any cracking found during any inspection required by the
AD. This would include any inspection specified in the procedures for
the optional modification. We find that adding the reference requested
by the commenter may clarify that any cracking found during the
optional modification must be repaired before further flight. Thus, for
clarification, we have revised paragraph (c) of this AD to specify that
the repair provisions in that paragraph apply to any cracking found
during an inspection required by this AD, including cracking found
during accomplishment of the modification specified in paragraph (d) of
this AD.
Request To Clarify Inspection Threshold
The commenter requests that we revise paragraph (d) of the proposed
AD to clarify that, if the optional modification is accomplished, the
threshold for the repetitive inspections of Zone B is extended to the
post-modification threshold specified in Tables 1 through 3 of Figure 1
of the service bulletin. The proposed AD does not include the words
``post-modification'' before the word ``threshold.'' The commenter does
not state any justification for its request.
We infer that the commenter is concerned that, because there are
other thresholds specified in the service bulletin, operators may be
confused about the new threshold for the repetitive inspections of Zone
B. We concur that this clarification may be helpful and have revised
paragraph (d) of this AD accordingly.
Request To Revise Inspection Terminology, Add Inspection Definition
The commenter requests that we revise paragraph (b) of the proposed
AD to refer to a ``detailed visual inspection'' instead of a ``detailed
inspection.'' The commenter also requests that we add an AD note
defining a ``detailed visual inspection.'' The commenter points out
that this note has appeared in other ADs.
We do not concur with the commenter's request to revise the
inspection terminology. The term ``detailed visual inspection'' was
changed to ``detailed inspection'' in Revision 2003.1 of the Air
Transport Association of America (ATA)/MSG-3 document, ``ATA Operator/
Manufacturer Scheduled Maintenance Development.'' We find that this
terminology should be readily understood by all affected operators, and
no change to the terminology is necessary.
We do concur with the commenter's request to add the standard AD
note defining a ``detailed inspection.'' This note was inadvertently
omitted from the proposed AD. Therefore, we have added a new Note 2 to
this AD and renumbered subsequent notes accordingly.
Request To Clarify Area of Inspection
The commenter requests that we revise the ``Summary'' section of
the proposed AD to clarify the area of inspection. The commenter states
that the statement that the proposed AD would require, ``repetitive
inspections to find fatigue cracking between the seal ribs of the front
spar web of the wing'' is not accurate. The commenter states that
inspections also extend outboard of the outboard seal rib to front spar
station inboard (FSSI) 713.
We concur with the intent of the commenter's request; however, we
find that the subject inspection area extends to FSSI 711, not FSSI 713
as stated by the commenter. We have revised the ``Summary'' of this
final rule accordingly. We find that this does not expand the scope of
the proposed AD because paragraph (b) of the proposed AD states that
the inspections must be accomplished ``per the Accomplishment
Instructions'' of Boeing Special Attention Service Bulletin 747-57-
2313, Revision 1, dated February 21, 2002. The ``Summary'' section of a
proposed AD is intended to provide only a very general description of
the proposed requirements, while the preamble more completely describes
the proposed requirements.
Request To Revise Preamble
The commenter requests that we make the following changes to the
preamble of the proposed AD:
[sbull] In the ``Discussion'' section of the proposed AD, identify
the model on which the 24-inch crack in the front spar web of the right
wing was found as a Boeing Model 747-200 series airplane, not a Model
747-100 series airplane.
[sbull] In the ``Discussion'' section of the proposed AD, state
that the cracks originated from a hole common to a rib post on the
front spar at FSSI 655.70, not FSSI 656.
[sbull] In the ``Related Rulemaking'' section of the proposed AD,
state that both AD 90-17-18, amendment 39-6702 (55 FR 33279, August 15,
1990), and AD 95-12-26, amendment 39-9279 (60 FR 34107, June 30, 1995),
refer to Boeing Service Bulletin 747-57A2259 as the appropriate source
of information for actions required by those ADs.
We partially agree with the commenter's requests:
[sbull] We agree that the original report of cracking was on a
Boeing Model 747-200 series airplane, not on a Model 747-100 as stated
in the proposed AD. The unsafe condition associated with this AD is
addressed on Model 747-200 series airplanes by the rulemaking action
associated with Rules Docket No. 2001-NM-228-AD, which we issued as a
notice of proposed rulemaking on February 24, 2003 (68 FR 10185, March
4, 2003).
[sbull] Section 1.C., ``Reason,'' of Boeing Special Attention
Service Bulletin 747-57-2313, Revision 1, states that the hole from
which the cracking originated was common to a rib post on the front
spar at FSSI 656. Thus, the proposed AD is consistent with the service
bulletin, and the change requested by the commenter is not necessary.
[sbull] AD 95-12-26 supersedes AD 90-17-18. Thus, the proposed AD
should have referred to the requirements of AD 95-12-26 instead of AD
90-17-18.
Regardless of these issues, neither the ``Discussion'' nor the
``Related Rulemaking'' section is restated in this
[[Page 50063]]
final rule. Thus, no change to the final rule is necessary in this
regard.
Explanation of Additional Change to Proposed AD
We have revised the service bulletin citation throughout this final
rule to delete references to Appendices A and B of Boeing Special
Attention Service Bulletin 747-57-2313, Revision 1. However, in
paragraphs (b)(1), (b)(2), and (d) of this AD, the references to
Appendix A of Boeing Special Attention Service Bulletin 747-57-2313,
Revision 1, have been retained because those paragraphs refer
specifically to the inspection thresholds and intervals specified in
Appendix A of the service bulletin. Also, we have retained the
reference to Appendices A and B in the citation of the original issue
of Boeing Special Attention Service Bulletin 747-57-2313, dated April
19, 2001, because those appendices are outside the numbered pages of
that service bulletin.
Conclusion
After careful review of the available data, including the comments
noted above, the FAA has determined that air safety and the public
interest require the adoption of the rule with the changes previously
described. The FAA has determined that these changes will neither
increase the economic burden on any operator nor increase the scope of
the AD.
Changes to 14 CFR Part 39/Effect on the AD
On July 10, 2002, the FAA issued a new version of 14 CFR part 39
(67 FR 47997, July 22, 2002), which governs the FAA's airworthiness
directives system. The regulation now includes material that relates to
altered products, special flight permits, and alternative methods of
compliance. However, for clarity and consistency in this final rule, we
have retained the language of the NPRM regarding that material.
Change to Labor Rate Estimate
After the proposed AD was issued, we reviewed the figures we use to
calculate the labor rate to do the required actions. To account for
various inflationary costs in the airline industry, we find it
appropriate to increase the labor rate used in these calculations from
$60 per work hour to $65 per work hour. The economic impact
information, below, has been revised to reflect this increase in the
specified hourly labor rate.
Cost Impact
There are approximately 109 airplanes of the affected design in the
worldwide fleet. The FAA estimates that 59 airplanes of U.S. registry
will be affected by this AD, that it will take approximately 25 work
hours per airplane to accomplish the required inspections, and that the
average labor rate is $65 per work hour. Based on these figures, the
cost impact of this AD on U.S. operators is estimated to be $95,875, or
$1,625 per airplane, per inspection cycle.
The cost impact figure discussed above is based on assumptions that
no operator has yet accomplished any of the requirements of this AD
action, and that no operator would accomplish those actions in the
future if this AD were not adopted. The cost impact figures discussed
in AD rulemaking actions represent only the time necessary to perform
the specific actions actually required by the AD. These figures
typically do not include incidental costs, such as the time required to
gain access and close up, planning time, or time necessitated by other
administrative actions.
Should an operator elect to do the optional modification of Zone B,
it would take approximately 480 work hours to accomplish at an average
labor rate of $65 per work hour. Parts cost would be approximately
$16,652. Based on these figures, the cost impact of the proposed
modification is estimated to be $47,852 per airplane.
Regulatory Impact
The regulations adopted herein 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. Therefore, it
is determined that this final rule does not have federalism
implications under Executive Order 13132.
For the reasons discussed above, I certify that this action (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. A final evaluation has been prepared for this action
and it is contained in the Rules Docket. A copy of it may be obtained
from the Rules Docket at the location provided under the caption
ADDRESSES.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by
reference, Safety.
Adoption of the Amendment
0
Accordingly, pursuant to the authority delegated to me by the
Administrator, the Federal Aviation Administration amends part 39 of
the Federal Aviation Regulations (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. Section 39.13 is amended by adding the following new airworthiness
directive:
2003-17-06 Boeing: Amendment 39-13280. Docket 2001-NM-178-AD.
Applicability: Model 747-100, 747SP, and 747SR series airplanes,
as listed in Boeing Special Attention Service Bulletin 747-57-2313,
Revision 1, dated February 21, 2002; certificated in any category.
Note 1: This AD applies to each airplane identified in the
preceding applicability provision, regardless of whether it has been
modified, altered, or repaired in the area subject to the
requirements of this AD. For airplanes that have been modified,
altered, or repaired so that the performance of the requirements of
this AD is affected, the owner/operator must request approval for an
alternative method of compliance in accordance with paragraph (f) of
this AD. The request should include an assessment of the effect of
the modification, alteration, or repair on the unsafe condition
addressed by this AD; and, if the unsafe condition has not been
eliminated, the request should include specific proposed actions to
address it.
Compliance: Required as indicated, unless accomplished
previously.
To find and fix fatigue cracking between the seal ribs of the
front spar web of the wing and outboard of the outboard seal rib to
front spar station inboard 711, which could result in fuel leakage
into the area of the inboard engines, and consequent increased risk
of a fire; accomplish the following:
Compliance Times
(a) Where the compliance times in the service bulletin specify a
compliance time interval calculated ``after the initial release of
this service bulletin,'' this AD requires compliance within the
interval specified in the service bulletin ``after the effective
date of this AD.'' In addition, where the compliance time for the
initial inspection in Tables 1 through 3 of Figure 1 of the service
bulletin specifies ``flight hours,'' this AD requires a compliance
time of ``total flight hours.''
Initial and Repetitive Inspections
(b) Do detailed, high frequency eddy current and ultrasonic
inspections to find cracking of the front spar web of the wing as
specified in paragraphs (b)(1) and (b)(2) of this AD, per the
Accomplishment Instructions of Boeing Special Attention
[[Page 50064]]
Service Bulletin 747-57-2313, Revision 1, dated February 21, 2002.
(1) Do the applicable initial or post-modification inspection at
the times specified for the inspections in Tables 1 through 3 of
Figure 1 of the Accomplishment Instructions or Appendix A of the
service bulletin.
(2) After doing the applicable initial or post-modification
inspection specified in paragraph (b)(1) of this AD: Repeat that
inspection within the applicable intervals specified in Tables 1
through 3 of Figure 1 of the Accomplishment Instructions or Appendix
A of the service bulletin.
Note 2: For the purposes of this AD, a detailed inspection is
defined as: ``An intensive visual examination of a specific
structural area, system, installation, or assembly to detect damage,
failure, or irregularity. Available lighting is normally
supplemented with a direct source of good lighting at intensity
deemed appropriate by the inspector. Inspection aids such as mirror,
magnifying lenses, etc., may be used. Surface cleaning and elaborate
access procedures may be required.''
Repair
(c) If any cracking is found during any inspection required by
this AD, including any inspection performed during accomplishment of
the optional modification per paragraph (d) of this AD: Before
further flight, repair per a method approved by the Manager, Seattle
Aircraft Certification Office (ACO), FAA; or per data meeting the
type certification basis of the airplane approved by a Boeing
Company Designated Engineering Representative who has been
authorized by the Manager, Seattle ACO, to make such findings. For a
repair method to be approved, the approval must specifically
reference this AD.
Optional Modification
(d) Accomplishment of the modification of Zone B per Part 2 of
the Accomplishment Instructions of Boeing Special Attention Service
Bulletin 747-57-2313, Revision 1, dated February 21, 2002, would
extend the threshold recommended in Tables 1 through 3 of Figure 1
of the Accomplishment Instructions or Appendix A of the service
bulletin for the repetitive inspections of Zone B, to the new post-
modification threshold specified in Tables 1 through 3 of Figure 1
of the service bulletin.
Previously Accomplished Inspections and Modifications
(e) Inspections and modifications done before the effective date
of this AD per Boeing Special Attention Service Bulletin 747-57-
2313, including Appendices A and B, dated April 19, 2001, are
considered acceptable for compliance with the applicable actions
specified in this AD.
Note 3: Boeing Special Attention Service Bulletin 747-57-2313,
Revision 1, dated February 21, 2002, recommends prior or concurrent
accomplishment of Boeing Alert Service Bulletins 747-57A2259, 747-
57A2266, and 747-54A2159. The modifications in those service
bulletins are required by AD 95-10-16, amendment 39-9233.
Alternative Methods of Compliance
(f) An alternative method of compliance or adjustment of the
compliance time that provides an acceptable level of safety may be
used if approved by the Manager, Seattle Aircraft Certification
Office (ACO), FAA. Operators shall submit their requests through an
appropriate FAA Principal Maintenance Inspector, who may add
comments and then send it to the Manager, Seattle ACO.
Note 4: Information concerning the existence of approved
alternative methods of compliance with this AD, if any, may be
obtained from the Seattle ACO.
Special Flight Permit
(g) Special flight permits may be issued in accordance with
sections 21.197 and 21.199 of the Federal Aviation Regulations (14
CFR 21.197 and 21.199) to operate the airplane to a location where
the requirements of this AD can be accomplished.
Incorporation by Reference
(h) Unless otherwise specified in this AD, the actions shall be
done in accordance with Boeing Special Attention Service Bulletin
747-57-2313, Revision 1, dated February 21, 2002. This incorporation
by reference was approved by the Director of the Federal Register in
accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be
obtained from Boeing Commercial Airplane Group, P.O. Box 3707,
Seattle, Washington 98124-2207. Copies may be inspected at the FAA,
Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton,
Washington; or at the Office of the Federal Register, 800 North
Capitol Street, NW., suite 700, Washington, DC.
Effective Date
(i) This amendment becomes effective on September 24, 2003.
Issued in Renton, Washington, on August 12, 2003.
Kyle L. Olsen,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 03-20986 Filed 8-19-03; 8:45 am]
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