[Federal Register Volume 61, Number 96 (Thursday, May 16, 1996)]
[Rules and Regulations]
[Pages 24675-24684]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-12020]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 94-NM-92-AD; Amendment 39-9618; AD 96-10-11]
RIN 2120-AA64
Airworthiness Directives; McDonnell Douglas Model DC-9 and DC-9-
80 Series Airplanes, Model MD-88 Airplanes, and C-9 (Military) Series
Airplanes
AGENCY: Federal Aviation Administration, DOT.
ACTION: Final rule.
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SUMMARY: This amendment supersedes an existing airworthiness directive
(AD), applicable to McDonnell Douglas Model DC-9 and DC-9-80 series
airplanes, Model MD-88 airplanes, and C-9 (military) series airplanes,
that currently requires certain inspections and structural
modifications. This
[[Page 24676]]
amendment requires additional inspections and structural modifications.
This amendment is prompted by an evaluation conducted by the
Airworthiness Assurance Working Group, which identified additional
inspections and structural modifications for mandatory action. The
actions specified by this AD are intended to prevent degradation in the
structural capabilities of the affected airplanes.
DATES: Effective June 20, 1996.
The incorporation by reference of ``DC-9/MD-80 aging Aircraft
Service Action Requirements Document,'' McDonnell Douglas Report No.
MDC K1572, Revision B, dated January 15, 1993, as listed in the
regulations, is approved by the Director of the Federal Register as of
June 20, 1996.
The incorporation by reference of ``DC-9/MD-80 Aging Aircraft
Service Action Requirements Document,'' McDonnell Douglas Report No.
MDC K1572, Revision A, dated June 1, 1990, as listed in the
regulations, was approved previously by the Director of the Federal
Register as of September 24, 1990 (55 FR 34704, August 24, 1990).
ADDRESSES: The service information referenced in this AD may be
obtained from McDonnell Douglas Corporation, 3855 Lakewood Boulevard,
Long Beach, California 90846, Attention: Technical Publications
Business Administration, Department C1-L51 (2-60). This information may
be examined at the Federal Aviation Administration (FAA), Transport
Airplane Directorate, Rules Docket, 1601 Lind Avenue, SW., Renton,
Washington; or at FAA, Transport Airplane Directorate, Los Angeles
Aircraft Certification Office, 3960 Paramount Boulevard, Lakewood,
California; or at the Office of the Federal Register, 800 North Capitol
Street, NW., suite 700, Washington, DC.
FOR FURTHER INFORMATION CONTACT: David Y. J. Hsu, Aerospace Engineer,
Airframe Branch, ANM-120L, FAA, Transport Airplane Directorate, Los
Angeles Aircraft Certification Office, 3960 Paramount Boulevard,
Lakewood, California 90712-4137; telephone (310) 627-5323; fax (310)
627-5210.
SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal
Aviation Regulations (14 CFR part 39) was published in the Federal
Register on November 10, 1994 (59 FR 56011). The action proposed to
supersede AD 90-18-03, amendment 39-6701 (55 FR 34704, August 24,
1990), which is applicable to McDonnell Douglas Model DC-9 and DC-9-80
series airplanes, and Model MD-88 airplanes, and C-9 (military) series
airplanes. That action proposed to require certain additional
structural modifications and inspections.
Interested persons have been afforded an opportunity to participate
in the making of this amendment. Due consideration has been given to
the comments received.
Support for the Proposal
Several commenters support the proposed rule.
Request for FAA to Review Future Revisions of the Service Action
Requirements Document (SARD)
One commenter requests that the FAA review all subsequent revisions
of service bulletins that are referenced in McDonnell Douglas Report
No. MDC K1572, ``DC-9/MD-80 Aging Aircraft Service Action Requirements
Document,'' Revision B, dated January 15, 1993 (hereafter referred to
as ``SARD, Revision B''), to determine acceptability for compliance
with the requirements of the proposal. The FAA concurs. Whenever the
FAA reviews and approves a service document, that document will
indicate that it has been approved by the FAA, and that if is
considered an acceptable alternative method of compliance for any
existing AD's. For example, two sources of service information
referenced in the final rule bear such a statement. (See page ii,
``Alternative Means of Compliance,'' of SARD, Revision B; and page 22,
paragraph 1.E. ``Approval,'' of McDonnell Douglas DC-9 Service Bulletin
53-230, Revision 1, dated January 12, 1993.)
Request to Permit Operators to Join in FAA's Review of Future Revisions
to the SARD
The same commenter also requests that the FAA, as part of the
review process, obtain input from affected operators prior to approving
any McDonnell Douglas service bulletin. The commenter states that this
would reduce the number of errors in service bulletins, which would
eliminate the need for revisions of service bulletins to correct any
errors in them.
The FAA does not concur. While the FAA recognizes the value of
operators' review of service bulletins, it considers their
participation to be more timely and appropriate during the development
of the service bulletin by the manufacturer, rather than after it has
been submitted to the FAA for approval. After the FAA has identified an
unsafe condition, the FAA relies upon the manufacturer to provide the
method to correct that unsafe condition. When that method of correction
of the unsafe condition results in the issuance of a service bulletin,
the FAA must review and approve that service bulletin based upon
whether that service bulletin positively addresses the identified
unsafe condition and whether that method of correction meets the
airworthiness requirements for the type design of the affected
aircraft. Further, operators may not be able to provide in- depth
engineering analysis, such as that performed by the FAA, since type
design data are proprietary and may not be available to all operators.
However, the Air Transport Association (ATA) of America has in
place a system whereby member operators are afforded the opportunity to
provide input to airworthiness concerns. The FAA encourages operators
to take advantage of this ATA system to effect changes to
manufacturer's service bulletins. Additionally, operators have the
option of contacting the manufacturer directly to resolve such
difficulties.
Request that Manufacturer Provide Alternative Rework Drawings to
Operators
The same commenter requests that, when an earlier version of a
rework drawing is referenced in any rulemaking action, the FAA ensure
that the manufacturer provide operators with the most recent revision
of that rework drawing if it has been approved by the FAA as an
alternative method of compliance for the requirements of that
rulemaking action.
The FAA does not concur. Section 21.99(b), of the Federal Aviation
Regulations [14 CFR 21.99(b)], ``Required design changes,'' requires
that the manufacturer make information on design changes that
contribute to the safety of the product available to all operators of
the affected product. However, the revised rework drawings may not
necessarily contribute to the safety of the product. The FAA encourages
operators to contact the manufacturer directly to obtain revisions of
rework drawings. However, in the event any operator finds it impossible
to accomplish the requirements of this AD due to the inability to
obtain necessary rework drawings, those operators are reminded of the
provisions of paragraph (h) of the final rule, which permit any
operator to apply for approval of an alternative method of compliance
with the requirements of the final rule.
[[Page 24677]]
Request for Removal of Certain Service Bulletins from Requirements
of the Rule
The same commenter requests that the proposed rule be revised by
removing McDonnell Douglas DC-9 Service Bulletins 53-174 and 53-147
from the requirements. These service bulletins are referenced in SARD,
Revision B, which is referenced in the proposal as the appropriate
source of service information. The commenter contends that these two
service bulletins do not fit within the parameters of the proposal
since they specify continual repetitive inspections after
accomplishment of the proposed modification. The commenter asserts that
this contradicts the stated purpose of the proposal, which is to
``reflect the FAA's decision that long term continued operational
safety should be assured by actual modification of the airframe.''
The FAA does not concur. The FAA finds that the commenter has
restated only a portion of the purpose of this rulemaking action; the
commenter omitted two key words from the Summary section of this
rulemaking action. The FAA's intent is to require ``modification of the
airframe, where feasible.'' Service Bulletin 53-174 specifies
replacement of a limited number of rivets with bolts and hi-lok
fasteners and installation of doublers in the non-ventral bulkhead web
and tee. Service Bulletin 53-147 specifies installation of an external
doubler and internal finger doublers between longerons (LN) 14L and 14R
in the aft pressure bulkhead skin splice doubler. Since fatigue testing
and service history have demonstrated that the location of the
modifications addressed in these two service bulletins is susceptible
to fatigue cracking, the FAA has determined that modification alone
cannot ensure safety of the fleet; therefore, repetitive inspections
must continue to be performed to prevent degradation in the structural
capabilities of the affected airplanes.
Along this same line, the same commenter states that it cannot
accomplish the inspections that are required to be performed following
accomplishment of the modification specified in McDonnell Douglas DC-9
Service Bulletin 53-174. The commenter notes that although the service
bulletin provides a method for accomplishing the modification, it does
not provide a method for accomplishing the inspections of the modified
structure. From this comment, the FAA infers that the commenter is
requesting a delay in issuance of the final rule until such time that
the manufacturer has developed an acceptable inspection method of the
modified structure. The FAA does not concur. The FAA does not consider
that delaying this action until that time is warranted since sufficient
technology currently exists to accomplish the follow-on inspections
within the compliance time. However, the FAA points out that for
airplanes on which modifications affect performing the required
inspections, operators must use the provisions of paragraph (h) of the
final rule to request, from the FAA, approval for an alternative method
of compliance.
Request to Reference Latest Revision of Service Bulletins
The same commenter requests a revision to the proposal to reference
two service bulletins that have been revised since issuance of the
notice. The commenter states that McDonnell Douglas DC-9 Service
Bulletin 57-129, Revision 3, dated November 6, 1987, has been re-issued
as two separate service bulletins: McDonnell Douglas DC-9 Service
Bulletin 57-129, Revision 5, dated November 10, 1994; and McDonnell
Douglas DC-9 Service Bulletin 57-200, dated November 10, 1994. The FAA
concurs. Three new notes have been added to the final rule: NOTE 4,
NOTE 11, and NOTE 12. These notes state that accomplishment of both of
these service bulletins is acceptable for compliance with the
requirement to accomplish Service Bulletin 57-129, Revision 3.
Request to Convert Compliance Time from Flight Hours to Flight
Cycles
The same commenter requests a revision to the proposal that would
provide further guidance for converting flight hours to an equivalent
number of flight cycles. The commenter notes that most operators track
rotatable components in terms of flight hours, rather than flight
cycles, as expressed in the service bulletins referenced in SARD,
Revision B. Further, the commenter contends that repairable components
are tracked neither by serial number nor by flight cycles/hours. The
commenter states that ten of the service bulletins listed in SARD,
Revision B, express thresholds in terms of flight cycles accumulated on
the affected component.
The FAA does not concur. In re-evaluating expressions of thresholds
in terms of flight cycles, the FAA has verified with several affected
operators (including the commenter) and has found that repairable and
rotatable components have been tracked by flight cycles, as well as
flight hours. Since this commenter did not submit utilization data for
each of its airplanes, the FAA could not provide an appropriate method
to convert flight hours to an equivalent number of flight cycles.
However, the FAA would address these unique circumstances, including
conversion of flight hours to flight cycles, under the alternative
method of compliance provisions of paragraph (h) of the final rule.
Request to Revise Compliance Threshold for One Service Bulletin
This same commenter requests a revision of the threshold specified
in McDonnell Douglas DC-9 Service Bulletin 53-60, Revision 1
(referenced in Table 2.3 of SARD, Revision B). The commenter states
that a more appropriate threshold would be ``prior to the accumulation
of 89,000 total landings,'' which would coincide with the threshold
specified in McDonnell Douglas DC-9 Service Bulletin 53-166 (referenced
in Table 2.1 of SARD, Revision B). The commenter notes that Service
Bulletin 53-166 recommends accomplishment of the modification described
in that service bulletin prior to the accumulation of 89,000 total
landings, while Service Bulletin 53-60 recommends accomplishment of the
modification described in that service bulletin prior to January 15,
1997. The commenter further states that Service Bulletin 53-60 must be
accomplished prior to the accomplishment of Service Bulletin 53-166.
The FAA does not concur. Service Bulletin 53-166 states that it
``assumes that Service Bulletins * * * 53-60 have been accomplished;''
it does not state that Service Bulletin 53-60 must be accomplished
prior to Service Bulletin 53-166. In fact, Service Bulletin 53-166 goes
on to state that ``if these service bulletins have not been
accomplished on applicable aircraft, contact the Douglas Aircraft
Company for special instructions.'' Further, the FAA points out that
the final rule does not require accomplishment of Service Bulletin 53-
60 prior to the accomplishment of Service Bulletin 53-166, but it would
permit such accomplishment. Therefore, no change to the final rule is
necessary.
Request to Revise Repair Approval Process
This same commenter questions why structural repairs accomplished
in accordance with the DC-9 Structural Repair Manual (SRM), which is an
FAA-approved document; and Douglas Service Rework Drawings, which, for
the most part, are FAA-approved documents, must be again approved by
the FAA for the purpose of this AD. The commenter notes that paragraph
(c) of
[[Page 24678]]
the proposal requires FAA-approval of structural repairs, including
those that are accomplished in accordance with either of these
documents, despite the fact that they are FAA-approved documents.
The FAA infers that the commenter is requesting that proposed
paragraph (c) be revised to allow repairs in accordance with the SRM
and Service Rework Drawings, without further approval by the ACO. The
FAA does not concur. The repairs required by paragraph (c) were not
intended to terminate the requirements for inspection contained in
paragraphs (a) and (b) of the AD. However, the inspection procedures
referenced in those paragraphs may not be appropriate for structure
repaired as required by paragraph (c). Therefore, it is necessary to
obtain ACO approval of such repairs in order to ensure that the
approval is conditioned upon identification of appropriate inspection
methods that will continue to meet the intent of paragraphs (a) and
(b). For example, if a crack identified as a result of an inspection
under paragraph (a) is within the limits specified for an appropriate
repair in the SRM, an operator would be required to obtain the ACO's
approval for that repair. The approval would be conditioned either on
the ACO's determination that the inspection required by paragraph (a)
continues to be appropriate, or on the operator's identification of an
acceptable alternative inspection method.
Request to Clarify Effect of Requirements on Supplemental Inspection
Document (SID) Program
The same commenter asks what effect the proposed requirement to
modify Principal Structural Elements (PSE) will have on AD 94-03-01,
amendment 39-8807 (59 FR 6538, February 11, 1994), which requires
implementation of a SID sampling program of structural inspections to
detect fatigue cracking. The commenter notes that, in many cases,
accomplishment of the terminating modifications required by the
proposal will affect the fleet-leader operator sampling (FLOS) program
of AD 94-03-01.
The FAA acknowledges that certain repair and modification
requirements of the final rule may affect the FLOS program of AD 94-03-
01. For this reason, standardization and continuity of repairs are
especially important in light of the complexity of the DC-9 SID
program. The FAA has determined that standardization and continuity of
repairs can best be maintained by having one single point of approval
[i.e., the Manager of the Los Angeles Aircraft Certification Office
(ACO)] for all repairs of cracks in Principal Structural Element (PSE),
including those required by this final rule.
Further, every repair of PSE structure requires a Damage Tolerance
Assessment (DTA) to be performed (of each repair) to establish its
effect on the original inspection requirements of the repaired
structure. The FAA considers that any repair of any cracked PSE without
the required DTA can only be considered temporary, and will eventually
need to be coordinated with the Manager of the Los Angeles ACO. A PSE
structure on which repairs are made without the required DTA and not
coordinated with the manufacturer and the Los Angeles ACO, becomes a
``discrepant PSE'' when the time arrives for that PSE to be re-
inspected. In these cases, the repair may need to be removed or
reworked at a later time. In either case, the Manager of the Los
Angeles ACO must ensure that all repairs of cracked PSE's comply with
the requirements of AD 94-03-01, as well as with the requirements of
this final rule.
Most methods of repair specified in the DC-9 SRM or in relevant
service bulletins, or Designated Engineering Representative (DER)-
designed repairs, do not include a continuing inspection program to
ensure that the repair is inspected at the same level of safety as the
original PSE structure. A DTA can be done most easily at the time of
repair, rather than at a later date when the details of the repair may
be hard to obtain and, undoubtedly, would be more costly. Currently,
the Manager and staff of the Los Angeles ACO are working very closely
with the manufacturer to expedite interim repair approval requests.
Such requests may be made under the provisions of paragraph (h) of the
final rule.
Request to Include Corrosion Inspections
Another commenter requests a revision to proposed paragraphs (a)
and (b) to include inspections to detect corrosion. The commenter
states that proposed paragraphs (a) and (b), as well as AD 90-18-03
only require inspections to detect cracking.
The FAA does not concur that revision is necessary. NOTE 4 of the
final rule (which was designated NOTE 2 in the proposal) and the Note
following paragraph A.1. of AD 90-18-03 state that corrective action is
required for discrepancies other than cracking. Additionally, on May
24, 1993, the FAA issued AD 92-22-08 R1, amendment 39-8591 (58 FR
32281, June 9, 1993), which requires the implementation of a corrosion
prevention and control program. Therefore, the FAA finds that it is
unnecessary to include in this final rule any additional inspections to
detect corrosion.
Request for Clarification of Requirements of Service Bulletin 55-31
The same commenter requests a revision to the proposal to clarify
the requirements specified in McDonnell Douglas DC-9 Service Bulletin
55-31, which is referenced in SARD, Revision B. The commenter notes
that confusion may arise because Service Bulletin 55-31 is listed in
various sections of SARD, Revision B.
The FAA concurs. Service Bulletin 55-31 is listed in Table 2.3 and
Table 2.4 of SARD, Revision B. Paragraph (b) of the final rule requires
inspections of aircraft structure specified in Table 2.3 or 2.4 of
SARD, Revision B, while paragraph (e) of the final rule requires
modifications of aircraft structure specified in Table 2.3 or 2.4 of
SARD, Revision B. A new NOTE 7 has been added to the final rule to
clarify that the revisions of the service bulletins that are listed
under ``Recommended Modification'' are acceptable for inspections
performed prior to the effective date of the final rule. Additionally,
NOTE 8 of the final rule (which was designated NOTE 5 in the proposal)
provides additional clarification by stating that only those revision
levels of the service bulletins listed in Tables 2.3 and 2.4 are
acceptable for compliance with the modification requirements of the
final rule. Therefore, the inspections described in Service Bulletin
55-31 are required to be performed in accordance with Revision 4, and
the modifications are required to be accomplished in accordance with
Revision 3 or Revision 4 of Service Bulletin 55-31.
Request to Delete FAA-Approval of Repair Methods
One commenter requests a revision to paragraph (c) of the proposal,
which requires repair of cracks prior to further flight in accordance
with a method approved by the Manager of the Los Angeles ACO. The
commenter states that this proposed requirement would impose a severe
hardship on operators since most operators work 365 days a year,
whereas, the Los Angeles ACO operates on a standard 5-day work week.
The commenter notes that this difference in hours of operation creates
a problem for operators to obtain FAA approvals for repair methods. As
an alternative to staffing the Los Angeles
[[Page 24679]]
ACO offices 24 hours a day, 7 days a week, the commenter suggests that
the FAA provide its engineers and managers in the Los Angeles ACO with
pagers.
The FAA does not concur. Since repairs are only required when
cracks are found during the inspections required by this final rule,
the FAA anticipates that operators will accomplish those inspections
and repairs at a maintenance base during regularly scheduled ``heavy''
maintenance visits. Therefore, the FAA anticipates that operators will
have ample time to obtain approvals from the Los Angeles ACO without
adversely affecting their operations.
Further, the FAA recognizes that the required modifications will
necessitate a large number of work hours to accomplish. However, the
thresholds specified in the service bulletins referenced in SARD,
Revision B, were developed only after extensive and detailed
consultations between a large number of operators of Model DC-9 series
airplanes and the manufacturer. Among other things, these consultations
were conducted in order to establish timeframes (for accomplishing
necessary actions) that would minimize the economic impacts on
operators to the maximum extent possible, while still maintaining
safety objectives. Consequently, where safety considerations allow, the
FAA attempts to impose thresholds that generally coincide with
operators' maintenance schedules.
Request for Clarification of When To Repair vs. When To Modify
The same commenter also requests clarification of the relationship
between proposed paragraph (c) and proposed paragraph (f). The
commenter points out that:
1. Paragraph (c) would require that, if any crack is found during
an inspection, it must either be repaired or the applicable terminating
modification must be installed; and
2. Paragraph (f) would require that the terminating modifications
be installed by the time the airplane accumulates a certain number of
landings.
The FAA concurs that clarification is warranted. Paragraph (c) of
the final rule is applicable to all airplanes, while paragraph (f) of
the final rule is applicable only to Model DC-9-10, -20, -30, -40, and
-50 series airplanes and C-9 (military) series airplanes.
Further, the repair or modification specified in paragraph (c) is
an ``on condition'' requirement; as such, the terminating modifications
required by paragraph (c) of the final rule are required to be
accomplished, prior to further flight, on the condition that cracking
is found. Paragraph (f) of the final rule, on the other hand, requires
the eventual modification of all applicable airplanes (prior to the
accumulation of 100,000 total landings), regardless of whether or not
cracking has been found.
Request for Clarification of the Rule's Relationship to Modification
Requirements of Other Related AD's
The same commenter points to an inconsistency that may exist
between several existing AD's that reference various service bulletins
(that are referenced in SARD, Revision B) and NOTE 6 of the proposal.
The commenter states that a majority of the service bulletins
referenced in SARD, Revision B, that describe procedures for
inspections, are required currently by various other existing AD's.
However, those AD's do not provide for termination of those inspections
by accomplishing the modifications described in those service
bulletins. Therefore, the commenter questions the intent of NOTE 6 of
the proposal, which states that the modifications required by
paragraphs (d) and (e) of the proposal do not terminate the inspection
requirement of other related AD's unless those other related AD's
specifically state so.
The FAA does not find any inconsistencies between proposed NOTE 6,
which is now designated as NOTE 14 in the final rule, and the
requirements of other related AD's. The NOTE clearly specifies that a
modification required by this final rule does not automatically
terminate inspections required by another AD, unless that other AD
specifically states that the modification does constitute terminating
action for that AD's inspection requirements (or unless this final rule
specifically states that the modification constitutes terminating
action for another AD).
Request for Alternatives to Modifications
Further, the same commenter supports the proposed modifications
specified in paragraph (e) of the proposal, but only in cases where:
1. A superior inspection technique is not subsequently developed;
2. There is no record, worldwide, of subsequent cracking of
aircraft structure that has had terminating action modification
incorporated;
3. Test data and service experience support that the terminating
action modification is, without a doubt, effective; and
4. The accomplishment of the modification would not pose the threat
of rework included damage/error, as evidenced by historical
catastrophic failures.
When these conditions do not exist, the commenter requests that the
FAA consider alternatives to the proposed modifications.
Since the commenter did not provide the specifics for any kind of
alternative, the FAA infers that the commenter is requesting that the
proposed inspections of paragraph (b) be continued repetitively,
without terminating modifications. In that case, the FAA does not
concur. The FAA has determined that the degree of assurance necessary
as to the adequacy of inspections needed to maintain the safety of the
aging transport airplane fleet, coupled with a better understanding of
the human factors associated with numerous repetitive inspections, has
caused the FAA to place less emphasis on repetitive inspections and
more emphasis on design improvements and material replacement. Thus, in
lieu of its previous position of allowing continual inspection, and
repair or modification on condition if cracking is found, the FAA has
decided to require, whenever practicable, airplane modifications that
remove the source of the particular aging phenomena.
Request to Supersede AD 88-24-08 R2
One commenter requests that the proposal be revised by deleting the
requirements of proposed paragraph (f), and including those
requirements in AD 88-24-08 R2, amendment 39-6469 (55 FR 1002, January
11, 1990). The commenter notes that proposed paragraph (f) refers to
McDonnell Douglas DC-9 Service Bulletin 53-230, Revision 1, dated
January 12, 1993; while AD 88-24-08 R2 refers to McDonnell Douglas DC-9
Alert Service Bulletin A53-230, Revision 3, dated September 28, 1989.
The commenter states that superseding AD 88-24-08 R2 would ease the
administrative burden on operators, in lieu of superseding the proposal
whenever the manufacturer issues new revisions of any of the service
bulletins that are referenced in the SARD.
The FAA does not concur. The modifications (specified in Service
Bulletin 53-230 and) required by paragraph (f) of the final rule
terminate the inspections (specified in Alert Service Bulletin A53-230
and) required by AD 88-24-08 R2. Alert Service Bulletin A53-230 does
not specify procedures for termination of the inspections described in
that service bulletin. Whereas, Service Bulletin 53-
[[Page 24680]]
230 describes procedures for modifications of the fuselage frames
between LN's 10L and 10R at various overwing stations between Y=484.000
and Y=851.000. As explained in paragraph (f) of the final rule,
accomplishment of the modifications specified in Service Bulletin 53-
230 terminates the inspection requirements of AD 88-24-08 R2. Further,
as stated in the Discussion section of the preamble to the notice,
although Service Bulletin 53-230 was not included in SARD, Revision B,
the FAA concurs with the recommendations of the Airworthiness Assurance
Working Group (AAWG), which recommended that modifications described in
it be made mandatory in order to prevent structural degradation of the
fleet. Therefore, the FAA finds it appropriate to include Service
Bulletin 53-230 in the modification requirements of the final rule.
However, the FAA will consider issuing separate rulemaking actions,
including supersedure of existing AD's, whenever the manufacturer
issues new revisions to the service bulletins referenced in those AD's.
Request To Delete Redundant Language Concerning Terminating
Modifications
One commenter asserts that proposed paragraph (g) is redundant to
proposed paragraphs (a) and (b), which state that the modifications in
the service bulletins terminate the inspection requirements. From this
comment, the FAA infers that the commenter is requesting the deletion
of proposed paragraph (g), which states that accomplishment of certain
modifications terminates certain inspection requirements. The FAA
concurs. Proposed paragraph (g) has been deleted from the final rule.
Request for Explanation for the Exclusion of Certain Service
Bulletins
This same commenter requests that proposed rule be revised to
include an explanation as to why MD-80 Service Bulletins 53-186 (which
is referenced in Tables 2.1 and 2.2 of SARD, Revision B) and 53-216
(which is referenced in Table 2.2 of SARD, Revision B) are excluded
from the proposed requirements. The FAA concurs and acknowledges that
the reason for excluding these service bulletins from the requirements
of the final rule was omitted unintentionally. AD 94-08-04, amendment
39-8875 (59 FR 18952, April 21, 1994) requires inspections to detect
cracking in the skin and doublers around the upper anticollision light
cutout, and repair, if necessary; and stress coining the plate nut
clearance holes; which are specified in those service bulletins.
Therefore, paragraph (g) of the final rule [which was designated
paragraph (h) in the proposal] has been revised to state that AD 94-08-
04 addresses the actions specified in Service Bulletins 53-186 and 53-
216; it is for this reason that the actions specified in those service
bulletins are excluded from the requirements of the final rule.
Along this same line, the FAA finds that the actions specified in
DC-9 Service Bulletin 54-30 are excluded from the requirements of the
final rule since AD 77-14-19, amendment 39-2971 (42 FR 36811, July 18,
1977), already addresses the actions specified in that service
bulletin. AD 77-14-19 requires repetitive inspections to detect fatigue
cracking of the engine pylon front spar attachments and upper cap; and
modification of cracked structure. Procedures for these actions are
described in DC-9 Service Bulletin 54-30. Paragraph (g) of the final
rule has been revised to reflect this change.
The FAA also finds that the actions specified in DC-9 Service
Bulletins 27-196 and 27-250 are excluded from the requirements of the
final rule since AD 92-11-10, amendment 39-8260 (57 FR 27149, June 18,
1992), already addresses the actions specified in these service
bulletins. AD 92-11-10 requires repetitive inspections to detect
cracking of the forward slat drive drums' bellcrank shafts, and
replacement, as applicable. Procedures for these actions are described
in DC-9 Service Bulletins 27-196 and 27-50. Paragraph (g) of the final
rule has been revised accordingly.
The FAA also finds that the actions specified in DC-9 Service
Bulletins 57-125 and 57-148 are excluded from the requirements of the
final rule since AD 96-01-05, amendment 39-9481 (61 FR 2403, January
26, 1996), already addresses the actions specified in those service
bulletins. DC-9 Service Bulletin 57-125 describes procedures for
replacement of the attach fittings of the main landing gear (MLG); and
DC-9 Service Bulletin 57-148 describes procedures for inspection and
modification of the attach fittings of the MLG. Since these actions
currently are required by AD 96-01-05, paragraph (g) of the final rule
has been revised to exclude these actions.
Additionally, paragraphs (a), (b), (d), (e) of the final rule have
been revised to note the exclusion provision of paragraph (g) of the
final rule.
Clarification of Provisions for Obtaining Alternative Methods of
Compliance (AMOC)
One commenter requests further guidance to determine exactly when
FAA-approval of an AMOC is necessary. The FAA acknowledges that
additional guidance may be warranted, and has added a new NOTE 1 to
provide this. The new note specifies that, when performance of the
requirements of the AD is ``affected,'' an operator should apply for
approval of an AMOC in order to show compliance with the AD. The
meaning of the term ``affected'' can be understood by applying it to
typical scenarios:
One scenario is when performance of the requirements of the AD is
``affected'' in such a way that the operator is unable to perform those
requirements in the manner described in the AD. An example of this is
when an AD requires a visual inspection in accordance with a certain
service bulletin, but the operator cannot perform that inspection
because of the placement of a repair doubler over the structure to be
inspected; in this case, ``performance of the AD is affected.''
Another scenario is when it is physically possible to perform the
requirements of an AD, but the results achieved are different from
those specified in the AD. An example of this is when an AD requires a
non-destructive test (NDT) inspection in accordance with a certain
service bulletin, and the operator is able to move the NDT probe over
the specified area in the specified manner, but the results are either
meaningless or inaccurate because of a repair doubler placed over that
area; in this case, ``performance of the AD is affected.''
While it is not possible to address every possible situation,
``affected'' is normally an easy standard to apply: either it is
possible to perform the requirements as specified in the AD and achieve
the specified results, or it is not possible. Therefore, if the
requirements of this AD cannot be performed, then operators must submit
a request for an approval of an AMOC from the FAA, in accordance with
the provision of paragraph (h) of the final rule.
Any requirement of an AD, such as a modification or repair doesn't
``affect performance of the AD;'' it is performance of the AD.
Accordingly, every AD includes a provision that states, ``Compliance
required as indicated, unless previously accomplished.'' If an operator
performs such a requirement before the AD is issued, the FAA is
confident that the operator will recognize that it has
[[Page 24681]]
already complied with the AD and no further action (including obtaining
approval of an AMOC) is required.
Request That FAA Publish Its Policies on Granting AMOC's for Aging
Aircraft AD's
One commenter requests a revision of the proposed rule to include
all FAA policies pertinent to granting approvals of alternative methods
of compliance for aging aircraft AD's. The commenter made specific
reference to an FAA memo, dated June 9, 1994, which outlined the
criteria that the Aircraft Certification Offices (ACO) would be using
to grant approvals for alternative methods of compliance with the aging
aircraft AD's. (The subject of the memo was ``Denial of Requests for
Extended Compliance Times with the Aging Aircraft Modification
Airworthiness Directives.'') The commenter notes that the FAA has been
inconsistent in granting approvals of alternative methods of compliance
for aging aircraft AD's.
The FAA does not concur. Part 39 of the Federal Aviation
Regulations (14 CFR part 39), ``Airworthiness Directives,'' is for the
purpose of correcting unsafe conditions that may exist or develop in
aircraft, not for the purpose of publishing FAA policy decisions. The
FAA points out that it will continue to use the criteria outlined in
the memo referenced by the commenter to review data substantiating
requests for alternative methods of compliance to the aging aircraft
AD's on a case-by-case basis. Since the commenter did not provide any
specific examples of inconsistencies in the approval of alternative
methods of compliance that have been granted by the FAA, the FAA cannot
address those inconsistencies. However, the FAA attempts, to the
maximum extent possible, to accommodate each operators' specific
operating conditions, aircraft configurations, maintenance practices,
and other variables, provided they do not adversely impact safety.
Requests to Clarify Validity of Previously Approved AMOC's
This same commenter requests a revision to the proposal to indicate
that alternative methods of compliance that were previously approved by
the FAA for the modification requirements of other related AD's
continue to be considered acceptable for compliance with the
requirements of the proposal. The commenter states that the proposal is
too limiting in that only those AMOC's that were previously approved
for the requirements of AD 90-18-03 are to be considered acceptable for
compliance with the requirements of the proposal. The commenter
contends that revising proposed rule to accept previously approved
AMOC's would preclude operators from needlessly resubmitting additional
requests for AMOC's for the inspections and modifications that are
required by proposed paragraphs (a), (b), (d), and (f).
The FAA does not concur. The intent of paragraph (i) of the final
rule [which was designated paragraph (j) in the proposal] is to have
approvals for alternative methods of compliance to AD 90-18-03 remain
in effect for this AD. The inspection requirements of paragraph (a) of
the final rule (contained in Table 2.1 and Table 2.2 of SARD, Revision
A and) is a restatement of paragraph A. of AD 90-18-03, and the
modification requirements of paragraph (d) of the final rule is a
restatement of paragraph B. of AD 90-18-03. However, other
modifications (contained in Table 2.3, Table 2.4, and Table 3.1 of
SARD, Revision B) that are required by this final rule provide for a
higher level of safety than that provided by other modifications
required by other related AD's. Therefore, alternative methods of
compliance that were previously approved by the FAA for those other
related AD's may not provide for an adequate level of safety as that
provided by the modifications required by the final rule; therefore,
they must be reviewed individually to determine their acceptability, as
provided in paragraph (i) of the final rule.
Request that Necessary Parts Be Available
This commenter further requests FAA's intervention to ensure that
the manufacturer take no longer than 15 days to provide required parts
to operators. This commenter states that it has taken up to 18 months
to obtain necessary parts for modifications required by AD's. The FAA
cannot concur with this commenter's request, since the FAA has no
regulatory requirement to ensure that manufacturers of aircraft produce
spare parts in a timely manner. Part 39 of the Federal Aviation
Regulations (14 CFR part 39), ``Airworthiness Directives,'' limits the
FAA's authority to correct findings of unsafe conditions that may exist
or develop in aircraft.
Regardless, the FAA has verified with the manufacturer that parts
necessary for the modifications required by the final rule will be
available to operators upon submission of a purchase order to the
manufacturer. Additionally, under the provisions of paragraph (h) of
the final rule, operators may apply for the approval of an alternative
method of compliance or adjustment of the compliance time if sufficient
parts are unavailable to operators to accomplish the requirements of
the final rule.
Request for Revision of Cost Estimate Figures
One commenter requests that the cost impact information of the
proposal be revised to reflect the ``true cost'' over the entire
``modification period.'' The commenter notes that, in the proposal, the
costs estimated ``over the initial 4-year time period,'' depicts an
inaccurately low figure, since only 33 percent of the service bulletins
referenced in SARD, Revision B, recommend a threshold of 4 years.
The FAA does not concur that revision is necessary. The economic
impact information, below, was developed with data provided by the
manufacturer. In this case, the cost estimate in the final rule was
developed by the McDonnell Douglas Corporation only after extensive and
detailed consultations with large numbers of operators of Model DC-9
and DC-9-80 series airplanes. The FAA acknowledges that only 33 percent
of the service bulletins referenced in the SARD recommend a threshold
of 4 years; the remaining 67 percent of the service bulletins recommend
a threshold based on the number of flight cycles the airplane has
accumulated or on the age of the airplane. Given the significant
differences in operators' usage of these airplanes, an accurate
assessment of when each airplane would reach that flight cycle
threshold would be nearly impossible to calculate accurately.
Additionally, there is no way of knowing how many airplanes will be
``phased'' out of service as they approach or exceed the original
economic life goal of these airplanes. Therefore, the FAA considers the
4-year time period as an appropriate baseline to calculate the
estimated costs for all of the actions required by the final rule.
Additionally, subsequent to the issuance of the notice, the FAA
reviewed the figures it used in calculating the cost of labor relevant
to accomplishing AD activity. In order to account for various
inflationary costs in the airline industry, the FAA finds it
appropriate to increase the labor rate used in these calculations from
$55 per work hour to $60 per work hour. The economic impact
information, below, has been revised to reflect this increase in the
specified hourly labor rate.
Editorial Changes to the Final Rule
For purposes of readability, the FAA has revised paragraphs (a),
(b), (d), and (e); NOTE 10 [which was designated
[[Page 24682]]
NOTE 4 in the proposal] and NOTE 13 [which was designated NOTE 5 in the
proposal] of the final rule to remove the parenthetical phrase that
describes the airplanes applicable to each Table in the SARD . A new
NOTE 2 has been added to the final rule to explain that Tables 2.1,
2.3, and 3.1 of the SARD are applicable to Model DC-9-10, -20, -30, -
40, and -50 series airplanes, and C-9 (military) series airplanes; and
Tables 2.2 and 2.4 of the SARD are applicable to Model DC-9-81, -82, -
83, and -87 (MD-81, -82, -83, and -87) series airplanes, and Model MD-
88 airplanes.
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.
Cost Impact
There are approximately 892 Model DC-9 and C-9 (military) series
airplanes of the affected design in the worldwide fleet.
The FAA estimates that 568 Model DC-9 and C-9 (military) series
airplanes of U.S. registry were originally affected by AD 90-18-03. The
requirements of that AD were estimated to take approximately 946 work
hours to accomplish, at a current average labor rate of $60 per work
hour. The cost for required modification kits was estimated to be
$15,140 per airplane. Based on these figures, the FAA estimated that
the cost impact of AD 90-18-03 on U.S. operators of Model DC-9 and C-9
(military) series airplanes will be $40,839,200, or $71,900 per
airplane, over the initial 4-year time period. (These figures do not
include the cost of downtime, planning, set-up, familiarization, or
tool acquisition.)
The FAA estimates that 511 Model DC-9 and C-9 (military) series
airplanes of U.S. registry will be affected by the new requirements
specified in this AD. The new additional requirements of this AD action
will take approximately 638 additional work hours per airplane to
accomplish, at an average labor rate of $60 per work hour. Required
parts will cost approximately $37,027 per airplane. Based on these
figures, the cost impact of the AD on U.S. operators is estimated to be
$38,481,877, or $75,307 per airplane, over a 4-year time period. (These
figures do not include the cost of downtime, planning, set-up,
familiarization, and tool acquisition.)
There are approximately 1,090 Model DC-9-80 series airplanes and
Model MD-88 airplanes of the affected design in the worldwide fleet.
The FAA estimates that 173 Model DC-9-80 series airplanes and Model
MD-88 airplanes of U.S. registry were originally affected by AD 90-18-
03. The requirements of that AD were estimated to take approximately 47
work hours to accomplish, at a current average labor rate of $60 per
work hour. The cost for required modification kits was estimated to be
$752 per airplane. Based on these figures, the FAA estimated that the
cost impact of AD 90-18-03 on U.S. operators of Model DC-9-80 series
airplanes and Model MD-88 airplanes will be $617,956, or $3,572 per
airplane, over the initial 4-year time period. (These figures do not
include the cost of downtime, planning, set-up, familiarization, or
tool acquisition.)
The FAA estimates that a total of 615 Model DC-9-80 series
airplanes and Model MD-88 airplanes of U.S. registry will be affected
by the new requirements specified in this AD. This increase in the
number of affected airplanes is due to various reasons, including
transfer of ownership and the fact that additional airplanes have
accumulated time-in-service since the issuance of AD 90-18-03 and have
reached the threshold for modification/inspection. The new additional
requirements of this AD action will take approximately 13 additional
work hours per airplane to accomplish, at an average labor rate of $60
per work hour. Required parts will cost an additional $943 per
airplane. Based on these figures, the additional cost impact of this AD
on U.S. operators is estimated to be $1,059,645, or $1,723 per
airplane, over a 4-year time period. (These figures do not include the
cost of downtime, planning, set-up, familiarization, or tool
acquisition.)
The cost impact figure discussed above is based on assumptions that
no operator has yet accomplished the currently required or the newly
required actions of this AD; however, it can reasonably be assumed that
a majority of affected operators have already initiated the inspections
and structural modifications required by AD 90-18-03 [retained in
paragraphs (a) and (d) of this AD] and many may have already initiated
the additional inspections and structural modifications in this new AD
action.
The number of required work hours, as indicated above, is presented
as if the accomplishment of the actions proposed in this AD were to be
conducted as ``stand alone'' actions. However, in actual practice,
these actions for the most part would be accomplished coincidentally or
in combination with normally scheduled airplane inspections and other
maintenance program tasks. Therefore, the actual number of necessary
additional work hours would be minimal in many instances. Additionally,
any costs associated with special airplane scheduling would be minimal.
Regulatory Impact
The regulations adopted herein will not have substantial direct
effects 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, in
accordance with Executive Order 12612, it is determined that this final
rule does not have sufficient federalism implications to warrant the
preparation of a Federalism Assessment.
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
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
1. The authority citation for part 39 continues to read as follows:
Authority: 49 USC 106(g), 40113, 44701.
Sec. 39.13 [Amended]
2. Section 39.13 is amended by removing amendment 39-6701 (55 FR
34704, August 24, 1990), and by adding
[[Page 24683]]
a new airworthiness directive (AD), amendment 39-9618, to read as
follows:
96-10-11 McDonnell Douglas: Amendment 39-9618. Docket 94-NM-92-AD.
Supersedes AD 90-18-03, Amendment 39-6701.
Applicability: Model DC-9-10, -20, -30, -40, and -50 series
airplanes; Model DC-9-81 (MD-81), -82 (MD-82), -83 (MD-83), and -87
(MD-87) series airplanes; Model MD-88 airplanes; and C-9 (military)
series airplanes; 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 (h) 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.
Note 2: For purposes of this AD, references to Tables 2.1, 2.3,
and 3.1 of the Service Action Requirements Document (SARD) are
applicable to Model DC-9-10, -20, -30, -40, and -50 series
airplanes, and C-9 (military) series airplanes; and Tables 2.2 and
2.4 of the SARD are applicable to Model DC-9-81, -82, -83, and -87
(MD-81, -82, -83, and -87) series airplanes, and Model MD-88
airplanes.
Compliance: Required as indicated, unless accomplished
previously.
To prevent structural failure, accomplish the following:
Note 3: Paragraph (a) of this AD restates the requirements for
an initial inspection and the repetitive inspections contained in
paragraph A. of AD 90-18-03. Therefore, for operators who have
previously accomplished at least the initial inspection in
accordance with AD 90-18-03, paragraph (a) of this AD requires that
the next scheduled inspection be performed within the specified
repetitive inspection interval after the last inspection performed
in accordance with paragraph A. of AD 90-18-03.
(a) Except as provided by paragraph (g) of this AD, within the
threshold for inspections specified in the service bulletins listed
in either Table 2.1 or Table 2.2 , as applicable, of ``DC-9/MD-80
Aging Aircraft Service Action Requirements Document,'' McDonnell
Douglas Report No. MDC K1572, Revision A, dated June 1, 1990
(hereinafter referred to as ``SARD, Revision A''), or within one
repetitive inspection period specified in those service bulletins
after September 24, 1990 (the effective date of AD 90-18-03,
Amendment 39-6701); whichever occurs later: Inspect to detect cracks
in accordance with those service bulletins. Repeat these inspections
thereafter at the intervals specified in the service bulletins
listed in either Table 2.1, or Table 2.2, as applicable, of SARD,
Revision A, until the applicable terminating modification required
by paragraph (d) of this AD is accomplished.
Note 4: Table 2.1 of SARD, Revision A, includes the inspections
specified in DC-9 Service Bulletin 57-129, Revision 3, dated
November 6, 1987. Since issuance of the SARD, Revision A, that
service bulletin has been re-issued as two separate service
bulletins: DC-9 Service Bulletin 57-129, Revision 5, and DC-9
Service Bulletin 57-200; both dated November 10, 1994. Therefore,
accomplishment of both DC-9 Service Bulletins 57-129, Revision 5,
and 57-200 is considered acceptable for compliance with the
inspections specified in DC-9 Service Bulletin 57-129, Revision 3.
Note 5: The service bulletin revision levels list under
``Recommended Modification'' in either Table 2.1 or Table 2.2, as
applicable, of SARD, Revision A, are acceptable revisions for
inspections performed prior to September 24, 1994.
(b) Except as provided by paragraph (g) of this AD, within the
threshold for inspections specified in the service bulletins listed
in Tables 2.3 and 3.1, or Table 2.4, as applicable, of ``DC-9/MD-80
Aging Aircraft Service Action Requirements Document,'' McDonnell
Douglas Report No. MDC K1572, Revision B, dated January 15, 1993
(hereinafter referred to as ``SARD, Revision B''), or within one
repetitive inspection period specified in those service bulletins
after the effective date of this AD, whichever occurs later: Inspect
to detect cracks in accordance with those service bulletins. Repeat
these inspections thereafter at the intervals specified in the
service bulletins listed in either paragraph (b)(1) or (b)(2) of
this AD, as applicable, until the applicable terminating
modification required by paragraph (e) of this AD is accomplished.
Note 6: Accomplishment of the inspections in accordance with
McDonnell Douglas DC-9 Service Bulletin 57-129, Revision 5, dated
November 10, 1994; and McDonnell Douglas DC-9 Service Bulletin 57-
200, dated November 10, 1994; is acceptable for compliance with the
inspections described in McDonnell Douglas DC-9 Service Bulletin 57-
129, Revision 3, which is referenced in SARD, Revision B.
(1) For Model DC-9-10, -20, -30, -40, -50, and C-9 (military)
series airplanes: The service bulletins listed in Tables 2.3 and 3.1
of SARD, Revision B. Or
(2) For Model DC-9-81, -82, -83, -87 (MD-81, -82, -83, -87), and
Model MD-88 airplanes: The service bulletins listed in Table 2.4 of
SARD, Revision B.
Note 7: The service bulletin revision levels list under
``Recommended Modification'' or ``Recommended Inspection'' in Tables
2.3 and 3.1, or Table 2.4, as applicable, of SARD, Revision B, are
acceptable revisions for inspections performed prior to the
effective date of this AD.
(c) If any crack is found during any inspection required by this
AD, prior to further flight, either accomplish the applicable
terminating modification in accordance with paragraph (d) or (e) of
this AD, or repair in accordance with a method approved by the
Manager, Los Angeles Aircraft Certification Office (ACO), FAA,
Transport Airplane Directorate.
Note 8: Detection of any discrepancy, other than cracking,
necessitates appropriate corrective action in accordance with the
provisions of part 43 of the Federal Aviation Regulations (14 CFR
part 43).
(d) Except as provided by paragraph (g) of this AD, prior to
reaching the incorporation thresholds listed in either Table 2.1, or
Table 2.2, as applicable, of SARD, Revision A or Revision B; or
within 4 years after September 24, 1990 (the effective date of AD
90-18-03); whichever occurs later: Accomplish the structural
modifications specified in the service bulletins listed in either
Table 2.1, or Table 2.2, as applicable, of SARD, Revision A or
Revision B. Accomplishment of these modifications constitutes
terminating action for the applicable inspections required by
paragraph (a) of this AD.
Note 9: Paragraph (d) of this AD restates the modification
requirements of paragraph B. of AD 90-18-03. As allowed by the
phrase, ``unless accomplished previously,'' if the requirements of
paragraph B. of AD 90-18-03 have been accomplished previously,
paragraph (d) of this AD does not require that they be repeated.
Note 10: The service bulletin revision levels listed under
``Recommended Modification'' in either Table 2.1, or Table 2.2, as
applicable, of SARD, Revision A, are acceptable revisions for
modifications accomplished prior to September 24, 1994.
Note 11: Accomplishment of the modification in accordance with
McDonnell Douglas DC-9 Service Bulletin 57-129, Revision 5, dated
November 10, 1994; and McDonnell Douglas DC-9 Service Bulletin 57-
200, dated November 10, 1994; is acceptable for compliance with the
modifications described in McDonnell Douglas DC-9 Service Bulletin
57-129, Revision 3, which is referenced in SARD, Revision A.
(e) Except as provided by paragraph (g) of this AD, prior to
reaching the incorporation thresholds listed in either Table 2.3, or
Table 2.4, as applicable, of SARD, Revision B, or within 4 years
after the effective date of this AD, whichever occurs later:
Accomplish the structural modifications specified in the service
bulletins listed in either Table 2.3, or Table 2.4, as applicable,
of SARD, Revision B. Accomplishment of this modification constitutes
terminating action for the applicable inspections required by
paragraph (b) of this AD.
Note 12: Accomplishment of the modifications in accordance with
McDonnell Douglas DC-9 Service Bulletin 57-129, Revision 5, dated
November 10, 1994, and McDonnell Douglas DC-9 Service Bulletin 57-
200, dated November 10, 1994; is acceptable for compliance with the
modifications described in McDonnell Douglas DC-9 Service Bulletin
57-129, Revision 3, which is referenced in SARD, Revision B.
Note 13: The service bulletin revision levels listed under
``Recommended Modification'' in either Table 2.3, or Table 2.4 of
SARD, Revision B, are acceptable revisions for modifications
accomplished prior to the effective date of this AD.
[[Page 24684]]
Note 14: The modifications required by paragraphs (d) and (e) of
this AD do not terminate the inspection requirements of any other AD
unless that AD specifies that any such modification constitutes
terminating action for those specified inspection requirements.
(f) For Model DC-9-10, -20, -30, -40, -50, and C-9 (military)
series airplanes: Prior to the accumulation of 100,000 total
landings, accomplish the modifications specified in McDonnell
Douglas DC-9 Service Bulletin 53-230, Revision 1, dated January 12,
1993. Accomplishment of these modifications constitute terminating
action for the inspections required by AD 88-24-08 R2, amendment 39-
6469.
(g) The McDonnell Douglas service bulletins that are listed
below, are addressed in the following separate rulemaking actions.
Therefore, the actions specified in these service bulletins that are
referenced in the following tables of SARD, Revision A or Revision
B, are excluded from the requirements of this AD.
------------------------------------------------------------------------
McDonnell Douglas Service Amendment
Table(s) Bulletin AD No. No.
------------------------------------------------------------------------
3.1................ DC-9 Service Bulletin 54- 77-14-19 39-2971
30.
2.1................ DC-9 Service Bulletin 27- 92-11-10 39-8260
196.
2.1................ DC-9 Service Bulletin 27- 92-11-10 39-8260
250.
2.1 and 2.2........ MD-80 Service Bulletin 53- 94-08-04 39-8875
186.
2.2................ MD-80 Service Bulletin 53- 94-08-04 39-8875
216.
2.1................ DC-9 Service Bulletin 57- 96-01-05 39-9481
125.
2.3................ DC-9 Service Bulletin 57- 96-01-05 39-9481
148.
------------------------------------------------------------------------
(h) 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, Los Angeles Aircraft Certification
Office (ACO), FAA, Transport Airplane Directorate. Operators shall
submit their requests through an appropriate FAA Principal
Maintenance Inspector, who may add comments and then send it to the
Manager, Los Angeles ACO.
Note 15: Information concerning the existence of approved
alternative methods of compliance with this AD, if any, may be
obtained from the Los Angeles ACO.
(i) Alternative methods of compliance previously granted for AD
90-18-03, amendment 39-6701, continue to be considered as acceptable
alternative methods of compliance for the relevant provisions of
this amendment.
(j) 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.
(k) The inspections and modifications shall be done in
accordance with ``DC-9/MD-80 Aging Aircraft Service Action
Requirements Document,'' McDonnell Douglas Report No. MDC K1572,
Revision A, dated June 1, 1990; and in accordance with ``DC-9/MD-80
Aging Aircraft Service Action Requirements Document,'' McDonnell
Douglas Report No. MDC K1572, Revision B, dated January 15, 1993,
which contains the following list of effective pages:
------------------------------------------------------------------------
Revision
letter
Page No. shown on Date shown on page
page
------------------------------------------------------------------------
List of Effective Pages............. B January 15, 1993.
Pages xi and xii....................
------------------------------------------------------------------------
The incorporation by reference of ``DC-9/MD-80 Aging Aircraft
Service Action Requirements Document,'' McDonnell Douglas Report No.
MDC K1572, Revision A, dated June 1, 1990, was approved previously
by the Director of the Federal Register in accordance with 5 U.S.C.
552(a) and 1 CFR part 51 as of September 24, 1990 (55 FR 34704,
August 24, 1990). The incorporation by reference of ``DC-9/MD-80
Aging Aircraft Service Action Requirements Document,'' McDonnell
Douglas Report No. MDC K1572, Revision B, dated January 15, 1993, is
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
McDonnell Douglas Corporation, 3855 Lakewood Boulevard, Long Beach,
California 90846, Attention: Technical Publications Business
Administration, Department C1-L51 (2-60). Copies may be inspected at
the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW.,
Renton, Washington; or at the FAA, Transport Airplane Directorate,
Los Angeles Aircraft Certification Office, 3960 Paramount Boulevard,
Lakewood, California 90712; or at the Office of the Federal
Register, 800 North Capitol Street, NW., suite 700, Washington, DC.
(l) This amendment becomes effective on June 20, 1996.
Issued in Renton, Washington, on May 8, 1996.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 96-12020 Filed 5-15-96; 8:45 am]
BILLING CODE 4910-13-U