[Federal Register Volume 77, Number 69 (Tuesday, April 10, 2012)]
[Rules and Regulations]
[Pages 21404-21420]
[FR Doc No: 2012-8450]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2007-0109; Directorate Identifier 2007-NM-235-AD;
Amendment 39-16990; AD 2012-06-09]
RIN 2120-AA64

Airworthiness Directives; Lockheed Martin Corporation/Lockheed
Martin Aeronautics Company Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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SUMMARY: We are adopting a new airworthiness directive (AD) for all
Lockheed Martin Corporation/Lockheed Martin Aeronautics Company Model
382, 382B, 382E, 382F, and 382G airplanes. This AD was prompted by a
report of incidents involving fatigue cracking and corrosion in
transport category airplanes that are approaching or have exceeded
their design service objective. This AD requires revising the
maintenance inspection program to include inspections that will give no
less than the required damage tolerance analysis for each principal
structural element (PSE), doing repetitive inspections to detect cracks
of all PSEs, and repairing cracked structure. We are issuing this AD to
maintain the continued structural integrity of the fleet.

DATES: This AD is effective May 15, 2012.
    The Director of the Federal Register approved the incorporation by
reference of a certain publication listed in the AD as of May 15, 2012.

ADDRESSES: For service information identified in this AD, contact
Lockheed Martin Corporation/Lockheed Martin Aeronautics Company,
Airworthiness Office, Dept. 6A0M, Zone 0252, Column P-58, 86 S. Cobb
Drive, Marietta, Georgia 30063; telephone<PHONE_NUMBER>; fax 770-494-
5445; email<EMAIL_ADDRESS>Internet http://www.lockheedmartin.com/ams/tools/TechPubs.html. You may review copies
of the referenced service information at the FAA, Transport Airplane
Directorate, 1601 Lind Avenue SW., Renton, Washington. For information
on the availability of this material at the FAA, call<PHONE_NUMBER>.

Examining the AD Docket

    You may examine the AD docket on the Internet at http://www.regulations.gov; or in person at the Docket Management Facility
between 9 a.m. and 5 p.m., Monday through Friday, except Federal
holidays. The AD docket contains this AD, the regulatory evaluation,
any comments received, and other information. The address for the
Docket Office (phone:<PHONE_NUMBER>) is Document Management Facility,
U.S. Department of Transportation, Docket Operations, M-30, West
Building Ground Floor, Room W12-140, 1200 New Jersey Avenue SE.,
Washington, DC 20590.

FOR FURTHER INFORMATION CONTACT: Carl Gray, Aerospace Engineer,
Airframe Branch, ACE-117A, FAA, Atlanta Aircraft Certification Office,
1701 Columbia Avenue, College Park, Georgia 30337; phone:<PHONE_NUMBER>;
fax:<PHONE_NUMBER>; email<EMAIL_ADDRESS>
SUPPLEMENTARY INFORMATION:

Discussion

    We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR
part 39 to include an AD that would apply to the specified products.
That NPRM was published in the Federal Register on November 14, 2007
(72 FR 64005) (corrected December 3, 2007 (72 FR 67998)). That NPRM
proposed to require revising the maintenance inspection program to
include inspections that will give no less than the required damage
tolerance rating for each structural significant item (SSI), doing
repetitive inspections to detect cracks of all SSIs, and repairing
cracked structure.

Comments

    We gave the public the opportunity to participate in developing
this AD. The following presents the comments received on the proposal
(72 FR 64005, November 14, 2007; corrected December

3, 2007 (72 FR 67998)) and the FAA's response to each comment.

Support for the Proposed AD (72 FR 64005, November 14, 2007; Corrected
December 3, 2007 (72 FR 67998))

    Safair and Lockheed Martin Aeronautics Company (LM Aero) concurred
with the proposed requirement to implement the Lockheed Martin Model
382, 382B, 382E, 382F, and 382G Series Aircraft Service Manual
Publication (SMP), Supplemental Structural Inspection Document (SSID),
SMP 515-C-SSID, Change 1, dated September 10, 2010 (``the SSID'').
    Lynden Air Cargo (Lynden) agreed that the SSID would provide an
acceptable way to comply with the maintenance program requirements of
the inspection procedures specified in section 121.370a of the Federal
Aviation Regulations (14 CFR 121.370a), which was superseded by section
121.1109 of the Federal Aviation Regulations (14 CFR 121.1109).

Request To Extend Comment Period

    The SSID identified eight individual ADs that affect the principal
structural elements (PSEs) identified in Section 4.0 (Principle
Structural Elements) of the SSID. (The individual ADs are identified in
the SSID in Section 2.0, Table 2.1, pages 2-3.) Lynden requested
additional time to comment on the proposed AD (72 FR 64005, November
14, 2007; corrected December 3, 2007 (72 FR 67998)) to compare the
compliance intervals and standards with those in the proposed AD, the
individual ADs, and the continuous airworthiness maintenance program
(CAMP). Lynden was unable to determine how the SSID addresses the
existing ADs, and added that the proposed AD did not indicate that it
would supersede the existing rules.
    We reopened the comment period to allow additional time for
operators to comment on the proposed AD (72 FR 64005, November 14,
2007; corrected December 3, 2007 (72 FR 67998)). We also provide the
following clarification of the relationship among the various programs.
The SSID can be used to show compliance for the baseline inspections
for section 121.1109(c)(1) of the Aging Airplane Safety Rule (section
121.1109(c)(1) of the Federal Aviation Regulations (14 CFR
121.1109(c)(1)). This AD adds other more broad and specific inspections
that supplement but do not conflict with other ADs. The SSID
inspections should identify safety issues related to the PSEs. When a
SSID inspection reveals a certain number of positive findings on a PSE,
that part--and only that part--of the PSE will be removed from the SSID
and addressed in an individual AD and associated service bulletin. The
remainder of the PSE will remain in the SSID and will be subject to the
SSID inspections only. If the problem area is not removed from the
SSID, the SSID requirements still apply, but at a lower priority until
the area is removed. We have not changed the final rule regarding this
issue.

Request To Consider Industry Participation in Lockheed Working Group
Sessions

    The proposed AD (72 FR 64005, November 14, 2007; corrected December
3, 2007 (72 FR 67998)) stated that members of the airline industry
participated with Lockheed in working group sessions and developed the
Supplemental Structural Inspection Program (SSIP) for the affected
airplanes, but Lynden reported that it was not consulted by the type
certificate (TC) holder, and it was not aware of or invited to
participate in any working group on this issue. Further, Lynden stated
that it understood that the TC holder used military operational and
design data for the basis of the SSID. Lynden, as the lead carrier for
the Model L-382 Master Minimum Equipment List (MMEL) and the largest
part 121 operator of the affected airplanes, would have provided
valuable input on the civil operation and maintenance of the affected
airplanes. Lynden requested that we consult the service difficulty
report (SDR) database for the operator's submitted data regarding the
structural inspection findings of the operator's CAMP.
    According to Lynden, the SDRs ensure that the airplane is in an
airworthy condition because fatigue cracks are found and reported
before any adverse effect on airworthiness. The existing inspections in
the CAMP reveal cracks based on existing inspection intervals, which,
in most cases, are identical to the inspection intervals in the CAMP
now being used by the operators. The SDRs also prove the accuracy of
the evaluation by the FAA and design approval holder (DAH) of
commercial usage (military usage for baseline structure is very similar
to commercial usage), based on objective criteria and information
submitted by the operators to the SDR database. Operators may request
approval of an alternative method of compliance (AMOC) based on the
existing CAMP.
    The information in the SSID is based on military usage, which
defined the baseline inspection requirements. Operators may be allowed
to extend the inspection intervals by completing an operational usage
evaluation (OUE) as specified in Lockheed Service Bulletin 382-57-84,
and requesting approval of an AMOC from the FAA. Recent analysis of the
usage data has shown that typical commercial operations of the affected
airplanes are at higher payloads than military operations with
significantly less time in training. Analysis and in-service cracking
data have also shown that the crack growth rate severity of typical
commercial usage is very similar to the baseline military usage.
Therefore, the FAA's evaluation of commercial usage is based on
objective criteria and information submitted by the operators. We have
not changed the final rule regarding this issue.

Request To Withdraw the Proposed AD (72 FR 64005, November 14, 2007;
Corrected December 3, 2007 (72 FR 67998)): No Unsafe Condition

    Lynden noted that the proposed AD (72 FR 64005, November 14, 2007;
corrected December 3, 2007 (72 FR 67998)) was prompted by incidents
involving fatigue cracking and corrosion in transport airplanes that
are approaching or have exceeded their design service objective. The
proposed AD was intended to maintain the continued structural integrity
of the entire fleet of Model 382, 382B, 382E, 382F, and 382G airplanes.
Lynden reported there have been no accidents involving fatigue cracking
and corrosion relating to this type design on its airplanes. Lynden
asserted that the program required by section 121.370a of the Federal
Aviation Regulations (14 CFR 121.370a) ensures that such accidents will
not happen. Lynden therefore questioned the conclusion that an unsafe
condition even exists. Lynden alleged that we have not provided
objective evidence of the unsafe condition in the affected airplanes,
but have general concerns regarding aging airplanes. Lynden added that
continued airworthiness of an airplane is ensured by the development of
extensive inspection and maintenance programs. In Lynden's case, those
maintenance requirements are detailed in an extensive CAMP, which has
been proven to ensure the airworthiness of its fleet for over 97,000
flight hours.
    We infer that Lynden was requesting that we withdraw the proposed
AD (72 FR 64005, November 14, 2007; corrected December 3, 2007 (72 FR
67998)), because no unsafe condition has been identified. We disagree.
The DAH performed several full-scale fatigue tests on the Model L-382,
and has developed a large data bank of service history

(including SDRs) to identify problem areas and PSEs that provide
objective evidence that an unsafe condition exists. The damage
tolerance analysis (DTA) assessments established inspection intervals
after many of the PSEs were identified. Initially the fatigue test and
service history data were used only to identify the problem areas
(i.e., PSEs) that were to receive DTA evaluation, and to validate the
DTA data. Every PSE received a DTA assessment. As part of the
assessment of each PSE, the DAH found that in some instances the DTA
did not correlate well with the fatigue test and service life data. In
these instances, the fatigue test and service life data were used to
establish the inspection intervals that are specified in the SSID.
    Lynden has developed an FAA-approved, operator-specific CAMP for
its fleet in accordance with section 121.1109 of the Federal Aviation
Regulations (14 CFR 121.1109) based upon the latest guidance and
documents from the DAH. The latest guidance and documents from the DAH
were provided in the Lockheed Martin Model L382, SMP 515-C-MASTER
Report, dated November 2010. This document should already be
incorporated into the operator's CAMP. Therefore, if the operator has
been performing its CAMP as required, adequate information is available
to perform the required inspections. The operator should already be in
compliance with the SSID. If the operator has made changes to the CAMP
to meet its maintenance schedules that were previously approved by the
FAA, the subject operator may request approval of an AMOC to the SSID
based on the existing CAMP, in accordance with the provisions of
paragraph (q) in this final rule. If the AMOC is approved by the FAA,
the operator will not need to change the CAMP except for minor changes
provided in the SSID, and would already be in compliance with this AD
except for the minor changes.
    As discussed previously, the SSID addresses an identified safety
issue on the affected airplanes and therefore must be mandated by an
AD. The inspection requirements in the SSID are required for the
continued safe operation of the aircraft. We have not changed the final
rule regarding this issue.

Request To Withdraw the Proposed AD (72 FR 64005, November 14, 2007;
Corrected December 3, 2007 (72 FR 67998)): Redundant With Existing
Programs

    Lynden asserted that it is already required to comply with the
intent and scope of the proposed AD (72 FR 64005, November 14, 2007;
corrected December 3, 2007 (72 FR 67998)) through accomplishment of the
CAMP, which ensures the continued airworthiness of its fleet through
constant analysis and surveillance. The CAMP and the improvements
required through the CAMP procedures ensure that fatigue cracks will be
detected before becoming critical. The CAMP will be used as the basis
for compliance with section 121.370a of the Federal Aviation
Regulations (14 CFR 121.370a) (which was superseded by section
121.1109(c)(1) of the Federal Aviation Regulations (14 CFR
121.1109(c)(1)). Lynden stated that the proposed requirements of the
SSID are comparable to the requirements already imposed under section
121.370a of the Federal Aviation Regulations (14 CFR 121.370a), and the
proposed grace period will provide nearly the same timeline. Lynden
noted that the proposed AD stated that fatigue cracking may increase as
a result of transport airplanes reaching or exceeding their design
service objective (DSO), and as a result of their increased utilization
and longer operation. Lynden asserted that the proposed AD would be
redundant with the requirements for the SSIP, which are contained in
section 121.370a of the Federal Aviation Regulations (14 CFR 121.370a).
Section 121.370a of the Federal Aviation Regulations (14 CFR 121.370a)
already requires incorporation of FAA-approved damage-tolerance-based
inspections into the maintenance program for aircraft structure
susceptible to fatigue cracking for the airplane to continue operating
after December 20, 2010.
    Lynden was concerned that the proposed AD (72 FR 64005, November
14, 2007; corrected December 3, 2007 (72 FR 67998)) will not establish
compliance with section 121.370a of the Federal Aviation Regulations
(14 CFR 121.370a) and will cause confusion and/or duplicative
recordkeeping requirements regarding whether a particular inspection is
acceptable for compliance. If the AD does establish compliance with
section 121.370a of the Federal Aviation Regulations (14 CFR 121.380a),
then it is unnecessary and redundant, since section 121.370a of the
Federal Aviation Regulations (14 CFR 121.370a) will ensure the
aircraft's structural integrity. On the other hand, if the AD does not
establish complete compliance, section 121.370a of the Federal Aviation
Regulations (14 CFR 121.370a) needs to be reviewed to ensure that it
establishes the level of safety originally anticipated by the FAA. In
either case, both requirements should not be needed to establish
continuous structural integrity of the affected airplanes.
    We infer that Lynden was requesting that we withdraw the proposed
AD (72 FR 64005, November 14, 2007; corrected December 3, 2007 (72 FR
67998)) as unnecessary because it is redundant with the CAMP or the
requirements of section 121.1109(c)(1) of the Federal Aviation
Regulations (14 CFR 121.1109(c)(1)). Some inspections were not included
in the SMP-515-C inspection program, and some operators do not have the
latest revision to this program, including the changes made by the SSID
and required by this AD. So an AD is necessary to mandate the
implementation of the SSID. Further, an AD would be necessary to ensure
continued operational safety if a related operational rule is changed
in the future. Except for some minor changes made by the DAH and
approved by the FAA, any operator with a CAMP already meets the
requirements of the SSID and this AD; no additional work would be
required, and no alternative method of compliance would be necessary to
demonstrate compliance. However, the SSID can also be used as a means
to show compliance for the baseline inspections for the section
121.1109(c)(1) of the Federal Aviation Regulations (14 CFR
121.1109(c)(1)) (which superseded section 121.370a of the Federal
Aviation Regulations (14 CFR121.370a). That rule requires operators to
incorporate FAA-approved damage-tolerance-based inspections and
procedures into the maintenance program for airplane structure
susceptible to fatigue cracking that could contribute to a catastrophic
failure on airplanes meeting the following criteria:
     Transport category airplanes
     Airplanes type certificated after January 1, 1958
     Turbine power airplanes
     Airplanes having a maximum type-certificated passenger
seating capacity of 30 or more, or a maximum payload capacity of 7,500
pounds or more
    Those airplanes must have FAA-approved damage-tolerance-based
inspections and procedures incorporated into the maintenance program
for airplane structure susceptible to fatigue cracking that could
contribute to a catastrophic failure. The SSID meets this requirement
for the affected airplanes. Therefore, no change to the final rule is
necessary regarding this issue.

Requests To Revise Repair Approval

    Safair, Lynden, and LM Aero requested that we change paragraph (n)
of the proposed AD (72 FR 64005, November 14, 2007; corrected December
3, 2007 (72 FR 67998)), which would have required repair ``using a
method approved by the Manager, Atlanta Aircraft Certification Office
(ACO), FAA.''
    Safair requested that we instead require repair ``in accordance
with an FAA-approved method'' to alleviate unnecessary burdens on both
the Atlanta ACO and the operators.
    Lynden noted that the preamble to the proposed AD (72 FR 64005,
November 14, 2007; corrected December 3, 2007 (72 FR 67998)) explained
that the AD would allow the use of FAA-approved methods for the repair,
but the proposed regulatory language would actually require each repair
to be specifically approved by the ACO. Lynden requested that the
preamble and regulatory language agree. Lynden believed that requiring
approval for each repair is an unworkable and unacceptable regulatory
burden for operators and the FAA. Lynden added that a typical Boeing
SSID AD does not contain such an onerous paragraph, but allows cracked
structure to be repaired in accordance with an FAA-approved method.
Lynden added that the FAA's Transport Airplane Directorate has
specifically promised to use the following language: ``Cracked
structure must be repaired prior to further flight in accordance with
an FAA-approved method.'' If the suggested language is used, operators
can perform repairs in accordance with previously acceptable methods,
techniques, and practices that are based on approved data--whenever
they find cracked structure, not just when performing inspections
required by the AD. Lynden asserted that it is extremely important for
the FAA to understand that an operator with an effective CAMP is
constantly inspecting for structural integrity, not just when an AD
requires an inspection. To ensure proper alignment with their
responsibilities to ensure the continuous airworthiness of the affected
airplanes, operators must not face conflicting, overlapping, or
confusing compliance requirements.
    LM Aero interpreted paragraph (n) in the proposed AD (72 FR 64005,
November 14, 2007; corrected December 3, 2007 (72 FR 67998)) as a
requirement to obtain an approval letter from the Atlanta ACO for every
repair carried out on PSEs with cracks detected by the SSID
inspections. LM Aero added that, in many cases, cracking detected by
the SMP-515-C inspection procedures in the SSID can be repaired with
existing FAA-approved repair procedures. Including the additional
requirement to obtain specific approval letters for each repair is
likely to place significant burden on both operators and the FAA. LM
Aero requested that we revise paragraph (n) of the proposed AD to add
the following provision:

    Existing FAA approved repair procedures that are applicable to
repair the damage detected, such as FAA approved Lockheed Model 382
Series Service Bulletins (when so stated in the Service Bulletin)
and the Lockheed Service Manual Publication SMP 583 Structural
Repair Manual [SRM], do not require further approval.

    Lynden concurred with LM Aero's comment.
    We agree with the commenters' rationale. Accordingly, we have
revised the final rule to add new Note 1 to paragraph (o) of this AD,
which explains the source of guidance for repairing damage. We also
added new Note 2 to paragraph (o) of this AD to explain that operators
may contact the Manager, Atlanta ACO, for information regarding the use
of published service data approved by the FAA for these repairs, as
required by paragraph (n) of this AD.

Request To Revise Terminology: ``PSE'' vs. ``SSI''

    LM Aero and Lynden requested that we revise the proposed AD (72 FR
64005, November 14, 2007; corrected December 3, 2007 (72 FR 67998)) to
be consistent with the SSID, which uses the term ``principle structural
element (PSE)'' instead of ``structural significant item (SSI).''
    We agree to standardize the terminology. The original term was
``Structural Significant Item (SSI).'' Although the two terms are
currently used interchangeably, we agree to use the latest terminology
in this AD. We have revised the final rule to replace ``SSI'' with
``PSE.''

Request To Revise Terminology: ``DTA Values'' vs. ``Inspection
Intervals''

    Lynden stated that neither the FAA nor the operators can ensure
compliance with the AD without a clear understanding of how the DTA was
conducted and without the required DTA values. If we were to accept LM
Aero's inspection intervals as ``DTA values,'' Lynden requested that we
revise the proposed AD (72 FR 64005, November 14, 2007; corrected
December 3, 2007 (72 FR 67998)) to correspond with the SSID. Lynden
noted, for example, that paragraph (g) of the proposed AD states, in
part, ``The required DTA value for each PSE is listed in the SSID.''
Lynden asserted that there are no DTA values or ratings listed in the
subject SSID.
    We partially agree. We agree to accept the DAH's inspection
intervals (presented in the SSID as ``DTA values''), and we have
revised the final rule to correspond to the SSID by changing ``DTA
values'' to ``inspection intervals'' throughout this final rule. We
disagree that compliance with the AD cannot be ensured without clear
understanding of how the DTA was conducted and without DTA values. The
operator is required to set up a tracking system for each inspection
and maintain that system at all times. The operator and the FAA can
track the status of the inspections using inspection numbers assigned
to each inspection requirement by the operator or they can track the
inspections by the procedure/card number defined by the SSID document
or any other procedure approved by the FAA. The DAH has given an
adequate description of its DTA methodology in Section 5.0 (Damage
Tolerance Analysis Methodology) of the SSID. This methodology should
provide the operators an understanding of how the DTA was conducted. In
addition, the FAA is familiar with the DAH's DTA procedures and has a
good understanding of how the DTA was conducted. The FAA has reviewed
and approved the DTA analysis and inspection intervals as approved in
the SSID. This information cannot be released to the operators because
it is the DAH's proprietary data. In addition, we have determined that
operators do not need this information to do the SSID inspections.

Request To Revise Applicability: Exclude Airplanes Subject to Section
121.1109 of the Federal Aviation Regulations (14 CFR 121.1109)

    LM Aero and Lynden requested that we revise the applicability of
the proposed AD (72 FR 64005, November 14, 2007; corrected December 3,
2007 (72 FR 67998)) to include only those airplanes on which the SMP-
515-C inspection program has not been incorporated and the applicable
service bulletins identified in the SSID have not been accomplished.
Lynden added that, according to Section 2.0 (Introduction) of the SSID,
some operators have not updated the SMP-515-C inspection program in
many years, and some commercially certified aircraft in other countries
may not have an SMP-515-C inspection program. Lynden noted that the TC
holder issued the SSID only for those operators without a CAMP or an
updated one, and the AD should

therefore apply only to airplanes that are not subject to section
121.370a of the Federal Aviation Regulations (14 CFR 121.370a).
    We disagree to change the applicability. The SSID addresses a
safety issue on all Model 382, 382B, 382E, 382F, and 382G airplanes as
the specified unsafe condition is likely to exist on all of these
products. The inspections in the SSID are necessary for the continued
safe operation of all applicable aircraft, and must be mandated by an
AD. If the operator has been performing the CAMP as required, the
operator is in compliance with the SSID, except for the minor changes.
We have not changed the final rule regarding this issue.

Request To Revise Applicability: Remove Airplanes With CAMPs

    Lynden alleged that the SDR database is directly related to the
specific inspections contemplated by the SSID and the proposed AD (72
FR 64005, November 14, 2007; corrected December 3, 2007 (72 FR 67998)),
and that the required reports are evidence that the FAA-approved part
121 CAMP is keeping the aircraft in an airworthy condition; i.e.,
defects are found and repaired before there is any adverse impact on
airworthiness.
    We infer that Lynden was requesting that we revise the
applicability to remove airplanes with CAMPs. We disagree. The purpose
of the SDRs is to help the FAA identify and address problem areas in
the fleet before a catastrophic failure occurs. The SDRs are used to
justify the inspection intervals in the SSID. The SDRs help maintain
affected airplanes in an airworthy condition because the reports advise
of fatigue cracks found before any adverse effect on airworthiness is
encountered. The existing inspections in the CAMP reveal cracks based
on existing inspection intervals. The inspection intervals in the SSID
are in most cases identical to the inspection intervals in the CAMPs
now being used by operators. The SDRs also verify the accuracy of the
FAA's and DAH's evaluations of commercial usage and are based on
objective criteria and information submitted by the operators to the
SDR database. Not all affected operators use a CAMP or have equal
maintenance programs. Consequently, and based on the SDRs of Lynden and
other operators, we have determined that the PSEs on the affected
airplanes are a potential safety issue that needs to be addressed.
    We have chosen to address this issue with an AD that will mandate
the inspections provided in the SSID, through an FAA-approved SSIP. We
intend to reduce the workload for the DAH, operators, and the FAA, and
still accomplish the intent of the AD. The SSID meets the requirements
for all Model 382, 382B, 382E, 382F, and 382G airplanes. Except for
some minor changes made by the DAH and approved by the FAA, any
operator with a CAMP is already in compliance with the SSID. If the
inspections per the CAMP have been accomplished, except for the minor
changes that may be incorporated into the program and accomplished as
required, no additional work is required by the operator. If the
operator has changed the CAMP to meet maintenance schedules previously
approved by the FAA, the operator may request approval of an AMOC to
the AD based on the existing CAMP. If an AMOC request is approved by
the Atlanta ACO, the operator would not have to change the CAMP, except
for minor changes, and would already be in compliance with this AD.
    In summary, airplanes with CAMPs are in compliance because either
(1) the initial inspection has been done in accordance with the CAMP or
(2) the inspection is not yet due, in which case the inspection would
be done in accordance with the SSID. But airplanes with CAMPs are still
affected by the AD because the repetitive inspection intervals may not
agree between the SSID and the CAMP. We have not changed the final rule
regarding this issue.

Request To Clarify Applicability: Airplanes Identified in SSID AD vs.
SSID

    Lynden requested that Section 3.0 (Affected Aircraft) be removed
from the SSID. Lynden asserted that an AD identifies the affected
airplanes, and conflicting information in the SSID does not aid
clarity.
    We disagree with the request. Paragraph (c) in this AD identifies
the affected airplanes, and the service documents identify the
respective individual affected serial numbers. Where there are
differences, the AD prevails. We have not changed the final rule
regarding this issue.

Request To Clarify Applicability: U.S.- vs. Non-U.S.-Registered
Airplanes

    While the proposed AD (72 FR 64005, November 14, 2007; corrected
December 3, 2007 (72 FR 67998)) reported there are ``91 airplanes of
the affected design in the worldwide fleet,'' Lynden stated that the
proposed AD would affect U.S.-registered airplanes only.
    We agree to provide clarification. Lynden is correct that the AD
affects U.S.-registered airplanes only. The quoted statement is from
the Cost of Compliance section of the proposed AD (72 FR 64005,
November 14, 2007; corrected December 3, 2007 (72 FR 67998)). In that
section, we report the number of affected airplanes operated worldwide,
but provide the cost estimates for only U.S.-registered airplanes. All
airplanes are identified in the AD; airplanes that are later added to
the U.S. registry will also be affected by this AD. We have not changed
the final rule regarding this issue.

Requests To Revise Compliance Time: Revise the Initial Compliance Time

    LM Aero stated that the compliance times for the initial
inspections specified in paragraph (h) of the proposed AD (72 FR 64005,
November 14, 2007; corrected December 3, 2007 (72 FR 67998)) provide
operators with considerable time to implement inspection requirements
that should already be in their inspection programs. LM Aero agreed
that a grace period to initiate the inspections (36 months as specified
in the proposed AD) might be necessary, but recommends against
exceeding the ``initial'' interval plus one ``recurring'' interval by
more than 12 months. LM Aero added that the compliance times, including
a grace period exceeding twice the ``initial'' interval on wing PSEs,
would exceed the crack growth ``Safety Limit'' defined in Section 5.0
(Damage Tolerance Analysis Methodology) of the SSID, and would
contravene the intent of section 25.571 of the Federal Aviation
Regulations (14 CFR 25.571) and FAA Advisory Circular (AC) 91-56B,
``Continuing Structural Integrity Program for Airplanes,'' dated March
7, 2008 (http://rgl.faa.gov/Regulatory--and--Guidance--Library/
rgAdvisoryCircular.nsf/0/c41f92c5f55751a58625740800686473/$FILE/
AC%2091-56B.pdf). LM Aero recommended the initial compliance times in
the following table.

                       Recommended Compliance Time
------------------------------------------------------------------------
                                     Commenter's recommended compliance
          Airplane status                           time
------------------------------------------------------------------------
Has not exceeded the initial \1\    Before the initial threshold plus 10
 threshold.                          percent of the specified interval.
Has exceeded the initial threshold  Before reaching the initial plus one
                                     recurring inspection interval, or
                                     within 36 months after the
                                     effective date of the AD, whichever
                                     occurs first.
Has exceeded the initial threshold  Within 12 months after the effective
 plus one recurring inspection       date of the AD, or before reaching
 interval.                           twice the initial threshold,
                                     whichever comes first.
Has exceeded twice the initial      Before the next flight.
 threshold.
------------------------------------------------------------------------
\1\ The ``initial'' threshold is specified in Section 6.3 of the SSID.

    Lynden concurred with this comment.
    We disagree with the requests to revise the compliance time. Most
SSIDs provide operators 12 months to incorporate the inspections into
the maintenance program. Then the compliance time starts for those
inspections that have exceeded the threshold; otherwise the first
inspection is due at the threshold. We have not changed the final rule
regarding this issue.

Request To Revise Compliance Time: Extend Repetitive Interval for
Sloping Longerons

    LM Aero questioned the repetitive inspection intervals specified in
paragraph (k) of the proposed AD (72 FR 64005, November 14, 2007;
corrected December 3, 2007 (72 FR 67998)) for the ``Special Condition''
of the sloping longeron at the fuselage station (FS) 1041 fitting (per
Special Inspections card (SP) 113). LM Aero stated that the proposed
12-month interval would be too frequent and would add a significant
burden on the operator to continually remove the FS 1041 fitting to
perform the inspection. Furthermore, frequent repeated removal would
likely result in excessive over-sizing of the holes, which would
require replacement of the sloping longeron (FS 737 to 1041). The
intent of this inspection is to provide an opportunity to inspect the
longeron for stress corrosion cracking that is hidden under the FS 1041
fitting. Although stress corrosion cracks that have not propagated
beyond the FS 1041 fitting do not affect the structural integrity of
the longeron, they will eventually propagate out from under the fitting
for which the SSID recommends replacement. The need to replace the FS
1041 fitting depends on crack findings during the task associated with
SP-109--which will also detect relatively long stress corrosion cracks
in the sloping longeron by the x-ray primary procedure No. 2. Lynden
concurred with this comment.
    For the reasons provided by LM Aero, we agree to revise the
repetitive intervals, specified in paragraph (l) in this final rule,
from 12 months to an interval that corresponds to the ``Special
Condition'' inspection interval currently in the SSID, which requires
the inspection when the FS 1041 fitting is replaced. Paragraph (l) in
this final rule agrees with the SSID revision for the inspection
requirements for PSE 53-50-13.

Request To Remove Repetitive Inspection Requirement for ``Special
Conditions''

    LM Aero asserted that the intent of the SSID ``Special Condition''
inspections is to provide an opportunity to perform an enhanced
inspection of the applicable PSE during another unscheduled maintenance
action--typically, the removal of a component or structural part. LM
Aero recommended against mandatory scheduled intervals for these
inspections, because of the potential for associated damage from
repetitive part removal and replacement. LM Aero agreed that the
inspections should be done in accordance with paragraph (j) of the
proposed AD (72 FR 64005, November 14, 2007; corrected December 3, 2007
(72 FR 67998)), if none of the ``Special Condition'' inspections are
part of an operator's maintenance program. Lynden concurred with this
comment.
    We agree that the subject inspections should be done only when the
part is removed for scheduled maintenance--not at regular intervals.
The inspection area is a PSE but not a problem area. The inspection
requires removing parts, and continually removing the part for
inspection will result in excessive damage to the airplane structure
compromising the use and value of the inspection. The current schedule
is adequate to maintain safety. Because more damage will be done by
removing the parts to do the inspection, we have changed this final
rule to refer to the exceptions noted in paragraph (j) of this AD to
agree with the provisions of the SSID.

Request To Revise Compliance Time: Extend Repetitive Interval for Aft
Engine Mount

    LM Aero also questioned the repetitive inspection interval
specified in paragraph (m) of the proposed AD (72 FR 64005, November
14, 2007; corrected December 3, 2007 (72 FR 67998)) for the ``Special
Condition'' inspection of the aft engine mount beam (SP-190). LM Aero
stated that the proposed 24-month interval would result in a
significant burden on the operator to remove the aft engine mount to do
the inspection. This inspection is intended to provide an enhanced
procedure for detecting cracking of the aft mount beam normally hidden
by the lord mount. The aft lord mount does not have a scheduled removal
time, and replacement is based on the condition found (cracks in the
rubber mounts). The inspections associated with SP-189 performed at 24-
month intervals will detect cracking in the aft mount beam that extends
beyond the lord mount. Lynden concurred with this comment.
    We agree, for the reasons provided by the LM Aero. The proposed
compliance time could also result in excessive hole over-sizing,
requiring replacement of the steel beam. We have revised paragraph (n)
of this final rule to require the repetitive inspection interval as
specified in the SSID when the aft lord mount is replaced. Paragraph
(n) in this final rule agrees with the revision in the SSID for the
inspection requirements for PSE 71-10-03.

Request To Revise Compliance Time: Allow Changes to Intervals Based on
Findings and Design Changes

    Lynden stated that Section 5.0 (Damage Tolerance Analysis
Methodology) of the SSID presents two steps: (1) Incorporating the
methodology for assessing/analyzing each PSE listed in Section 4.0
(Principle Structural Elements) that validates the assigned DTA value;
and (2) implementing inspection intervals established for each PSE
based on the DTA and the value assigned. During the actual
accomplishment of the PSE inspections, findings are evaluated to
determine

whether the results are within the anticipated safety limits, i.e.,
within assigned values. When implemented, this requirement would
provide a methodology to allow adjustments to the inspection intervals
based on findings, changes in design, and implemented repairs and
alterations.
    We infer that Lynden was requesting that we revise the proposed AD
(72 FR 64005, November 14, 2007; corrected December 3, 2007 (72 FR
67998)) to allow for adjustments to the inspection intervals based on
the suggested criteria. We disagree. Section 5.0 (Damage Tolerance
Analysis Methodology) of the SSID clearly describes the DTA and
methodology, and Section 6.0 (Structural Inspection Requirements) of
the SSID clearly specifies the required inspection intervals for each
PSE. As previously stated we have evaluated the document and supporting
data, and have established that the methodology presented in the SSID
will ensure that the identified unsafe condition will be corrected. All
the information that the operator needs to incorporate into the
maintenance inspection program is the inspection procedures and the
inspection intervals, in Section 6.0 (Structural Inspection
Requirements) of the SSID. The discrepancy reporting requirements
specified in Section 7.0 (Discrepancy Reporting) of the SSID must also
be included. The DTA Methodology in Section 5.0 (Damage Tolerance
Analysis Methodology) of the SSID provides the basic information needed
to develop the inspection intervals provided in Section 6.0 (Structural
Inspection Requirements) of the SSID. The inspection intervals are
already provided, so operators do not need the detailed analysis. By
incorporating inspection intervals provided in Section 6.0 (Structural
Inspection Requirements) of the SSID, the operator is already in
compliance with Section 5.0 (Damage Tolerance Analysis Methodology)
because the intervals were based on Section 5.0 (Damage Tolerance
Analysis Methodology). This AD does not allow adjustments to the
inspection intervals without FAA approval. Operators may request AMOCs
for this purpose in accordance with procedures specified in paragraph
(q) of this AD.

Request To Revise Compliance Time: Require SSID Incorporation by
Certain Date

    Lynden requested that we revise the proposed compliance time to a
specific date, such as December 2010--for the pending DTA requirements
in section 121.370a of the Federal Aviation Regulations (14 CFR
121.370a).
    We partially agree. December 20, 2010, is the date by which
operators must incorporate an inspection program into their maintenance
program to address the baseline structure inspections required by the
Aging Aircraft Safety Rule (14 CFR 121.1109, ``Supplemental
Inspections''). Operators may either use the SSID or incorporate their
own FAA-approved inspection program for baseline structure. Lockheed
has agreed, once the AD is issued, to provide operators that have
incorporated certain inspections into their maintenance program with a
revision of Lockheed Service Manual SMP-515-C that includes the SSID
requirements. Therefore, most if not all operators have complied with
this AD by that date, with no additional work required of operators. We
have not changed the final rule regarding this issue.

Request To Revise Compliance Time: Match CAMP's Inspection Intervals

    Lynden questioned whether operators will be able to comply with the
proposed requirements in the proper timeframe, adding that several
proposed inspection intervals would be problematic. Lynden emphasized
that the CAMP's intervals have ensured the structural integrity of its
fleet for 97,000 flight hours of civil operation in the most difficult
civil operating conditions envisioned by the type design. Lynden
observed that the proposed inspection intervals are slightly shorter
than those established by Lynden's CAMP, and suggests that changing
these intervals could introduce the potential for maintenance error,
with possible harmful results. Lynden stated that the proposed AD must
correspond with its CAMP to ensure compliance and structural integrity
without unnecessary duplication and cost.
    We infer that Lynden was requesting that we revise the proposed
inspection intervals to match those in its CAMP. We disagree. In
developing an appropriate compliance time for this AD, we considered
the practical aspect of accomplishing the inspections within intervals
of time that correspond to typical scheduled maintenance for affected
operators. But since the various operators have different maintenance
schedules, we could not provide optimal schedules for each operator in
the AD. As previously explained, operators who perform the CAMP as
required should already be in compliance with the SSID, except for the
differences noted. Operators with FAA-approved revisions to their CAMP
to meet maintenance schedules may request an AMOC to the AD, in
accordance with the provisions of paragraph (q) of this AD, based on
the existing CAMP to adjust the maintenance schedule, provided no
interval exceeds the DTA-established inspection intervals mandated by
the AD and presented in the SSID. We have not changed the final rule
regarding this issue.

Request To Revise Compliance Time: Extend Time To Incorporate SSID

    Lynden was concerned that the compliance times in the SSID and the
AD do not contain the exact same language. Determining exact compliance
is essential to an operator's efficient and effective management of
ADs. Lynden requested additional time to ensure that its current CAMP
establishes compliance with the AD, which will in turn comply with
section 121.1109 of the Federal Aviation Regulations (14 CFR 121.1109).
Lynden has already worked with its Principal Aviation Safety Inspector
(PASI) to ensure that its program can comply with the requirements of
section 121.1109 of the Federal Aviation Regulations (14 CFR 121.1109)
and the December 2010 deadline. Lynden has followed FAA Advisory
Circular (AC) 120-93, ``Damage Tolerance Inspections for Repairs and
Alterations,'' dated November 20, 2007 (http://rgl.faa.gov/Regulatory--
and--Guidance--Library/rgAdvisoryCircular.nsf/0/
f73fd2a31b353a71862573b000521928/$FILE/AC%20120-93.pdf), regarding the
actual accomplishment and implementation of the section 121.370a of the
Federal Aviation Regulations (14 CFR 121.370a) program. The operator's
PASI has agreed to the carrier's phased approach and will ensure the
following:
    1. The maintenance program for the airplane includes FAA-approved
damage-tolerance-based inspections and procedures for airplane
structure susceptible to fatigue cracking that could contribute to a
catastrophic failure. These inspections and procedures account for the
effects of adverse repairs, alterations, and modifications on fatigue
cracking of airplane structure.
    2. The Atlanta ACO has approved the damage-tolerance-based
inspections and procedures, including any revisions. Lynden has already
included the SSID's damage-tolerance-based inspections and procedures
in its CAMP.
    We agree with the request to revise the compliance time in this AD.
As stated previously, we have changed the compliance time of paragraph
(g) of this final rule to 12 months after the effective date of the AD
for operators to incorporate the requirements of the

SSID into their maintenance program. Lynden has a CAMP, and the latest
guidance and documents from the DAH should already be incorporated into
the operator's CAMP. So operators performing their CAMP as required
already have the necessary information to perform these inspections.
The operator should already be in compliance with the SSID so it should
not be necessary to revise the compliance time. If the operator has
made changes to the CAMP to meet its maintenance schedules that were
previously approved by the FAA, the subject operator may request an
AMOC based on the existing CAMP; if the AMOC is approved by the FAA,
the operator will not have to change the CAMP, and they would already
be in compliance with this AD, except for the minor changes.

Request To Clarify Compliance Times (DTA Initial Values)

    Lynden questioned how operators will know how to comply with
paragraph (g) of the proposed AD (72 FR 64005, November 14, 2007;
corrected December 3, 2007 (72 FR 67998)), since the SSID provides a
methodology for accomplishing the DTA but does not assign the initial
values (compliance times).
    We disagree that the SSID does not assign the initial values. The
initial and repetitive inspections are provided in Section 6.0
(Structural Inspection Requirements) of the SSID, along with a
reference to the inspection procedure for each PSE. Paragraph (g) of
this AD requires operators to incorporate the information in the SSID
(inspection intervals and procedures) into their maintenance inspection
programs within 12 months. Paragraph (i) of this AD specifies the
compliance time for accomplishing the initial inspections. We have not
changed the final rule regarding this issue.

Request To Revise Cost Estimate: Cost for SSID Incorporation Is for the
Fleet, Not per Airplane

    LM Aero noted that the estimated cost of implementing the AD
applies to operators that do not currently follow the Model 382 SMP-
515-C inspection program. To LM Aero's knowledge, all U.S. operators
currently use this program (although it is not yet mandated by the
FAA), and the latest revision includes the intent of the SSID. Revising
the maintenance program therefore should be considered a one-time
effort of 600 hours for the entire fleet (not per airplane). Lynden
concurred with this comment.
    We agree. The proposed AD (72 FR 64005, November 14, 2007;
corrected December 3, 2007 (72 FR 67998)) inadvertently stated that
revising the maintenance program would take 600 work hours per
airplane. We have revised the Costs of Compliance section of this final
rule accordingly.

Request To Revise Cost Estimate: Include Work Hours for Recordkeeping

    Lynden stated that the estimated costs specified in the proposed AD
(72 FR 64005, November 14, 2007; corrected December 3, 2007 (72 FR
67998)) do not include the additional recordkeeping requirements
necessary to comply with the AD. Lynden owns and operates six of the
affected airplanes, all under part 121 and all under a program
developed to comply with section 121.370a of the Federal Aviation
Regulations (14 CFR 121.370a). Lynden noted that operators must report
structural issues under the SDR rules as well as reporting findings to
the TC holder in accordance with the AD. This duplicative action must
take place at the time of the inspections and repairs so that the
airplane can be approved to return to service and accomplishment with
the AD requirements can be recorded.
    We infer that Lynden was requesting that we revise the cost
estimate in the proposed AD (72 FR 64005, November 14, 2007; corrected
December 3, 2007 (72 FR 67998)) to include additional time for
recordkeeping. We disagree. Based on the best data available, the
manufacturer provided the number of work hours necessary to do the
basic required actions. This number represents the time necessary to
perform only the actions actually required by this AD. We recognize
that, in doing the actions required by an AD, operators might incur
incidental costs in addition to the direct costs. The cost analysis in
AD rulemaking actions, however, typically does not include incidental
costs such as the time required for recordkeeping or other
administrative actions. Those incidental costs, which might vary
significantly among operators, are almost impossible to calculate.
    Further, the SSID requirements are already part of the maintenance
program, so if the inspections have been done as specified in the SSID,
no additional work is required. Most of the information required by the
SSID will be identical to the SDRs except for some minor changes. To
simplify the reporting requirements, operators may use one report for
both the SSID inspections and the SDRs. For these reasons we find that
there will be very little additional cost for recordkeeping once the
maintenance program is revised to incorporate the SSID requirements. We
have not changed the final rule regarding this issue.

Request To Revise Cost Estimate: Account for Duplicate Inspections

    The Cost of Compliance section in the proposed AD (72 FR 64005,
November 14, 2007; corrected December 3, 2007 (72 FR 67998)) explained
the following:

    The number of inspection work hours * * * is presented as if the
accomplishment of the actions in this proposed AD [(72 FR 64005,
November 14, 2007; corrected December 3, 2007 (72 FR 67998))] are to
be conducted as ``stand alone'' actions. However, in actual
practice, these actions for the most part will be done
coincidentally or in combination with normally scheduled airplane
inspections and other maintenance program tasks. Therefore, the
actual number of necessary additional inspection work hours will be
minimal in many instances. * * *

    Lynden alleged that this is not true for its current program, and
that if the AD is issued as proposed, Lynden would be required to
duplicate inspections to comply with its program and the AD.
    We infer that Lynden was requesting that we revise the cost
estimates in this AD. We disagree. Each operator's inspection schedule
will be different, and we cannot account for the individual costs
incurred by each operator. We have not changed the final rule regarding
this issue.

Request To Revise Cost Estimate: Account for Discrepancies Between AD
and SSID

    Lynden contended that the cost estimates specified in the proposed
AD (72 FR 64005, November 14, 2007; corrected December 3, 2007 (72 FR
67998)) would be more accurate if we reconcile the differences between
the AD and the SSID. Lynden asserted that the estimated costs are based
on the assumption that the proposed inspection intervals were in line
with the inspection intervals already used by air carriers. Lynden
stated that these intervals do not align and would add scheduling
complexities and associated costs for the operators. Lynden requested
that we revise the proposed AD based on Lynden's estimated costs, since
Lynden operates the most affected airplanes.
    We disagree with the request to revise the cost estimate. Where
safety considerations allow, we try to set compliance times that
generally coincide with operators' maintenance schedules. But since
schedules vary substantially, we cannot accommodate each operator's
optimal scheduling in

each AD. Therefore, we do not consider it appropriate to attribute to
the AD the costs associated with the type of special scheduling that
might otherwise be required. Each AD does allow individual operators to
request approval to adjust the compliance time via an alternative
method of compliance, based on data showing that the adjustment will
not adversely affect safety. In any event, any compliance time
adjustments would have little effect on costs since most of the
inspections already align with each operator's maintenance program. We
have not changed the AD regarding this issue.

Request To Address Imprecision in SSID

    Lynden objected to the proposed AD (72 FR 64005, November 14, 2007;
corrected December 3, 2007 (72 FR 67998)) incorporating the SSID ``by
reference'' because the SSID is not precisely written. Lynden alleged
that other supplemental structural inspection documents adopted through
ADs clearly delineate the methodology used to develop the requirements
for determining the structural elements and the inspection intervals.
Lynden stated that those documents also clearly lay out the damage
tolerance values for each element. Lynden added that Section 5 (DTA
Methodology) is not like the sections of other SSIDs referenced in
other ADs. Those SSIDs clearly establish the DTA methodology and the
DTA value assigned to each SSI. Lynden added that such clarity is
necessary for appropriate changes to the maintenance program and for
the assignment and continued evaluation of the inspection intervals
implemented under that program.
    Lynden made no specific request to change the proposed AD (72 FR
64005, November 14, 2007; corrected December 3, 2007 (72 FR 67998)),
but we provide the following explanation to address Lynden's concerns.
    We disagree with the assertion that the SSID is not precisely
written. As explained previously, an operator's CAMP is based on the
latest guidance and documents from the DAH, as provided in the Lockheed
Martin Model L382 SMP 515-C-MASTER Report, dated November 2010.
    We also disagree that the SSID does not clearly delineate the
methodology used to develop the requirements for determining the PSEs
and the inspection intervals. Section 4.0 (Principle Structural
Elements) of the SSID provides enough information for operators to
determine how the PSEs were developed. Sections 4.0 (Principle
Structural Elements) and 8.0 (Inspection Zone Description) also provide
enough information to identify each PSE and its location on the
aircraft by zones. Section 5.0 (Damage Tolerance Analysis Methodology)
clearly explains the DTA methodology, and Section 6.0 (Structural
Inspection Requirements) clearly states the required inspection
intervals (damage tolerance values) for each of the PSEs. Further,
operators have already incorporated into the CAMP the inspection
procedures required to perform the SSID inspections on SP cards
(special inspection cards) and ST cards (structural inspections cards).
The operators have not advised of any concerns about these inspections,
and therefore must be following the procedures to perform the
inspections without difficulty. The inspection procedure/card number to
be used for each inspection is clearly identified in the first column
of the table in Section 6.0 (Structural Inspection Requirements) of the
SSID. Also, the required inspection intervals (assumed to be the damage
tolerance values referenced in the comments) are clearly defined in the
fourth and fifth columns of the table in Section 6.0 (Structural
Inspection Requirements) of the SSID. Operators are required to set up
a tracking system for each inspection, and to maintain that system at
all times. Operators and the FAA can track the status of the
inspections using inspection numbers assigned by the operator to each
inspection requirement, or operators can track the inspections by the
procedure/card number defined by the SSID document or any other
procedure approved by the FAA.
    We have reviewed and approved the DTA and inspection intervals as
approved in the SSID. This information is the DAH's proprietary data,
and we cannot release it to the operators. Further, operators do not
need this information to accomplish the SSID requirements.
    Each manufacturer's SSID is different, and each DAH has a different
approach regarding methods for developing the data, information they
need to provide to accomplish the required inspections, and reporting
procedures. The different overseeing ACOs also have authority to
approve whatever data they deem necessary to meet the requirements of
the AD, provided the data meet the intent of the FAA regulations,
policies, and guidance materials. We find that the SSID meets those
requirements.
    We have not changed this final rule regarding these issues.

Request To Address General Differences Between AD and SSID

    Lynden was concerned about differences noted between the proposed
AD (72 FR 64005, November 14, 2007; corrected December 3, 2007 (72 FR
67998)) and the SSID, and made several assertions based on these
alleged differences.
    1. The SSID's stated purpose is to capture a point in time to help
civil operators establish compliance with section 121.1109(c)(1) of the
Federal Aviation Regulations (14 CFR 121.1109(c)(1)).
    We partially agree with Lynden's position. The SSID inspections are
necessary for the continued safe operation of the affected airplanes,
and therefore must be mandated by an AD. However, the SSID can also be
used to show compliance for the baseline inspections for the Aging
Airplanes Safety Rule (14 CFR 121.1109(c)(1)). That rule requires
operators to incorporate FAA-approved damage-tolerance-based
inspections and procedures into the maintenance program for airplane
structure susceptible to fatigue cracking that could contribute to a
catastrophic failure on airplanes meeting the following criteria:
     Transport category airplanes.
     Airplanes type certificated after January 1, 1958.
     Turbine power airplanes.
     Airplanes having a maximum type-certificated passenger
seating capacity of 30 or more, or a maximum payload capacity of 7,500
pounds or more.
    The SSID meets the requirements for the affected airplanes.
    2. Section 121.1109 of the Federal Aviation Regulations (14 CFR
121.1109) is tied to the operator's CAMP, which can be continually
adjusted, with FAA approval, to accommodate improvements in design,
production, maintenance, and operations. Lynden added that an AD is
``carved in stone'' and may be changed only through an AMOC or a
superseding AD, which require expenditures of time and money by the
operator, the DAH, and the FAA.
    We partially agree with Lynden. Because the subject regulation is
tied to each operator's CAMP, which may be adjusted to accommodate such
improvements, we required the DAH to develop a separate document--the
SSID--and have mandated its incorporation by this AD, so that the
inspection requirements in the SSID cannot be revised by the operator
without approval by the Atlanta ACO. The inspection program may be
incorporated into operators'

maintenance programs in one of two ways: (1) By developing a separate
maintenance inspection document that stands alone and requires that
only those instructions in the SSID be accomplished in accordance with
the AD, or (2) by incorporating the SSID inspections into the existing
maintenance program. Either method is approved for the SSID AD, because
they are both considered part of an operator's maintenance program. As
Lynden noted, those inspections can then be changed only by an AMOC
approved by the FAA, or by a revision to the SSID followed by a new or
superseding AD that mandates the new requirements.
    3. The SSID is adequate for its stated purpose, but it does not
provide the certainty and objectivity required to be incorporated into
a rule.
    We disagree that the SSID lacks certainty and objectivity. As
previously explained, the inspection intervals and procedures are
clearly identified in Section 6.0 (Structural Inspection Requirements)
of the SSID, and the PSEs are identified in Section 4.0 (Principle
Structural Elements). And, if the operator has been performing the CAMP
as required, adequate information is available to perform the required
inspections, and the operator should already be in compliance with the
SSID except for the noted changes.
    No change is necessary in this final rule to address these
assertions.

Request To Address Additional Differences Between AD and SSID

    Lynden asserted that the SSID is inadequate, and will need
considerable revision and additions to satisfy the intent and purpose
of FAA Advisory Circular (AC) No. 91-56, ``Supplemental Structural
Inspection Program for Large Transport Category Airplanes,'' dated May
6, 1981 (now 91-56B, dated March 7, 2008). Lynden was concerned that it
will need an AMOC immediately to establish compliance with the intent
of the AD. Further, the AD changes the SSID in significant portions.
Lynden stated that, to ensure proper compliance, the SSID must align
properly with the proposed requirements of paragraphs (k) through (m)
of the proposed AD (72 FR 64005, November 14, 2007; corrected December
3, 2007 (72 FR 67998)).
    Lynden also requested that we ensure that Section 6.0 (Structural
Inspection Requirements) of the SSID and paragraphs (h) through (m) of
the proposed AD (72 FR 64005, November 14, 2007; corrected December 3,
2007 (72 FR 67998)) match exactly. Reconciling these differences would
(1) ensure that any changes to the SSID can be quickly reconciled with
the final rule and any unique air carrier requirements; (2) ensure that
an appropriate AMOC can be approved by the FAA without unnecessary
explanation or confusion; (3) allow the original equipment manufacturer
itself to apply for an AMOC to change the DTA and/or assigned values
based on design changes; and (4) enhance compliance.
    We agree with the request and made the requested revisions (in
paragraphs (j) through (n) in this final rule) to ensure that the
requirements of the AD align with the SSID accordingly. We agree that
the SSID must align with the AD, but the AD is the prevailing source
and we have determined these intervals to be appropriate.

Request To Clarify Section 6.0 (Structural Inspection Requirements) of
SSID

    Lynden requested that we account for conflicts and confusing
information in Section 6.0 (Structural Inspection Requirements) of the
SSID:

    The inspection intervals provided in this Section should be
taken as the minimum required intervals for a typical cargo
transport operational usage with average payloads not exceeding
20,000 lbs. For routine carriage of cargo in excess of 30,000 lbs,
the inspection intervals for wing lower surface PSEs should be
reduced by a factor of 2. * * * In no circumstances should the
operator extend these inspection intervals without having completed
an LM Aero Operational Usage Evaluation and obtaining FAA approval
for an updated SMP 515-C inspection program.

    Lynden asserted that there is no definition of the term
``routine,'' and no requirement for deviations if the operator has
obtained an OUE. Lynden questioned whether an operator with an FAA-
approved program developed to comply with section 121.370a of the
Federal Aviation Regulations (14 CFR 121.370a) would need an AMOC to
comply with the proposed AD (72 FR 64005, November 14, 2007; corrected
December 3, 2007 (72 FR 67998)). Lynden further questioned whether an
operator would have an automatic AMOC if it completed an OUE and
obtained FAA-approval of the updated inspection program through its
local Flight Standard District Office (FSDO). Lynden was concerned
about potential conflicts and confusion between the SSID and the
proposed AD, and notes a specific example of confusing information,
where Section 6.3 of the SSID includes the caveat of ``later than +10%
of the specified interval.'' Lynden questioned whether this indicates
that the proposed AD would allow the addition of 10% to all intervals
without additional approval.
    We agree to provide clarification. In this AD, ``routine'' refers
to typical cargo transport operational usage with an average payload of
30,000 pounds, rather than the defined typical usage of 20,000 pounds;
in that case the inspection intervals should be reduced by a factor of
2.
    AMOCs are never automatically approved. The operator must
substantiate, and we must approve, any AMOC for a different compliance
method or compliance time not specifically identified in the AD. The
OUE and the +10% extension have not been evaluated or approved by the
FAA, so these may not be approved as AMOCs to this AD without further
substantiation that these methods provide an equivalent level of
safety. Further, the OUE will vary from operator to operator, so we
must review each AMOC on a case-by-case basis in lieu of including this
information in this AD. We have not changed the final rule regarding
this issue.

Request To Address Errors in SSID and Clarify Use of References in AD

    Lynden noted certain errors and omissions throughout the SSID,
including references to certain documents.
    We infer that Lynden was requesting that we revise the proposed AD
(72 FR 64005, November 14, 2007; corrected December 3, 2007 (72 FR
67998)) to explain and correct the noted errors in the SSID. We
disagree with the request, and we disagree that the SSID contains
errors that would affect compliance with the requirements of this AD.
In the SSID, the PSEs are clearly identified in Section 4.0 (Principle
Structural Elements), and the locations and inspection requirements are
clearly identified in Sections 6.0 (Structural Inspection Requirements)
and 8.0 (Inspection Zone Description), and these cannot be changed
without FAA approval. All the information necessary to accomplish the
AD is in Sections 4.0 (Principle Structural Elements), 6.0 (Structural
Inspection Requirements), 7.0 (Discrepancy Reporting), and 8.0
(Inspection Zone Description) of the SSID, a stand-alone document.
Lynden notes that Section 4.0 (Principle Structural Elements) omits
Chapter 52, the PSEs, which are required to comply with Section 6.0
(Structural Inspection Requirements), but there are no SSID PSEs for
the doors in Chapter 52. The two PSEs identified in Section 6.0
(Structural Inspection Requirements) in Chapter 52 are actually located
on the fuselage and not on the doors, so those

PSEs are listed under Chapter 53 in Section 4.0 (Principle Structural
Elements). Those PSEs are referenced in Chapter 52 in Section 6.0
(Structural Inspection Requirements), because they are part of the door
surround structure. We have not changed the final rule regarding this
issue.

Request To Verify Compliance With Section 121.1109 of the Federal
Aviation Regulations (14 CFR 121.1109)

    Lynden suggested that the SSID was based on a menagerie of
methodologies to determine the inspection intervals, and that the
proposed changes to these intervals are based on an unclear
understanding of the original analysis. Neither the intervals proposed
by the SSID nor the changes proposed in paragraphs (i) through (m) of
the proposed AD (72 FR 64005, November 14, 2007; corrected December 3,
2007 (72 FR 67998)) can be tracked to a clear, concise, objective DTA
evaluation--as required by paragraph (g) of the proposed AD. The
proposed AD stated that compliance with the AD including the SSID
establishes compliance with section 121.1109 of the Federal Aviation
Regulations (14 CFR 121.1109). Lynden requested that we restate this in
the final rule.
    We partially agree with Lynden. We agree to restate that compliance
with the AD establishes compliance with section 121.1109(c)(1) of the
Federal Aviation Regulations (14 CFR 121.1109(c)(1)). We have revised
this final rule accordingly by adding this information in new Note 3 to
paragraphs (g) through (p) of this AD. But we disagree that changes to
the inspection interval are based on an unclear understanding of the
original analysis. We have previously described the different bases for
the SSID, and have explained that all the inspection intervals were
originally established using a DTA. We might consider different
intervals through requests for AMOCs if the service history data,
fatigue test results, or risk analysis does not correlate well with the
DTA, or if service history shows no discrepancies in the PSE inspection
area following inspections as directed by the SSID. And we might
consider different intervals to a calendar schedule if discrepancies
exist within a given time period regardless of the aircraft usage, or
to fit the operator's maintenance program schedule (although that
interval cannot exceed the interval established by a DTA). Changes in
inspection intervals must be substantiated by fatigue testing and
extensive service history. We might consider a different DTA-based
inspection, based on existing data. Or we might consider a different
DTA-based inspection interval if a risk analysis shows an extremely low
probability of fatigue damage occurring.

Request To Address Differences Between This (SSID) AD and Individual
ADs

    Lynden was concerned that Table 2.1 on page 2-3 of the SSID might
conflict with the various requirements of the individual ADs identified
in the SSID and the proposed inspection intervals of the proposed AD
(72 FR 64005, November 14, 2007; corrected December 3, 2007 (72 FR
67998)) or the requirements of section 121.1109 of the Federal Aviation
Regulations (14 CFR 121.1109). Lynden stated that the individual ADs
must be reconciled appropriately, superseded as appropriate, to ensure
continued compliance.
    We disagree that it is necessary to revise this final rule. This AD
adds inspections that supplement but do not conflict with other ADs.
The SSID inspections will identify safety issues related to the PSEs.
When a SSID inspection has a certain number of positive findings on a
PSE, then that part of the PSEs will be removed from the SSID and
addressed in an individual service bulletin and associated AD. The rest
of the PSEs will remain in the SSID and will be subject to the SSID
inspections only. We have not changed the final rule regarding this
issue.

Request To Address Differences in PSEs Identified in SSID and Customer-
Specific Programs

    Lynden stated that the last sentence of the second paragraph of
Section 4.0 (Principle Structural Elements) of the SSID clearly
indicates that the inspection intervals derived from the analysis for
the United States Air Force have already been incorporated into
operator-specific ``SMP-515-C-X Hercules Series Inspection Programs.''
Lynden requested that we revise the proposed AD (72 FR 64005, November
14, 2007; corrected December 3, 2007 (72 FR 67998)) to reconcile the
PSEs identified in Section V of the customer-specific SMP-515-C-X
inspection programs that have been ``superseded'' by the PSEs
identified in the SSID. In further support of its request, Lynden has
provided the FAA with its analysis of the SSID against its FAA-approved
program (SMP-515-C-113). The analysis revealed few, but significant,
differences.
    We agree that the information in the SSID is based on military
usage, which was used to define the baseline inspection requirements.
As explained previously, analysis and in-service cracking data have
shown that the crack growth rate severity of typical commercial usage
is very similar to the baseline military usage. Our evaluation of
commercial usage is therefore based on objective criteria and
information submitted by the operators. As stated previously, we accept
the DAH's inspection intervals presented in the SSID as ``DTA values,''
and have revised this final rule to change ``DTA values'' to
``inspection intervals'' to correspond to the SSID.
    But we disagree that the differences are significant. The DAH
carefully reviewed and evaluated the operator's maintenance program,
and considered the civilian usage of the affected airplanes. Our intent
is to reduce the workload of the DAH, operators, and the FAA, and still
accomplish the intent of the AD. The SSID meets the requirements for
the affected airplanes. Except for some minor changes made by the DAH
and approved by the FAA, any operator with a CAMP is already in
compliance with the SSID, except for the minor changes. The SSID
requirements are already a part of the operators' maintenance programs.
If the operator has made changes to the CAMP to meet its maintenance
schedules that were previously approved by the FAA, the subject
operator may request an AMOC to the SSID based on the existing CAMP. If
this is approved by the FAA, the operator will not have to change the
CAMP, and would already be in compliance with this AD except for the
minor changes in the SSID.

Request To Address Differences Between This AD and AD 92-10-14,
Amendment 39-8249 (57 FR 21727, May 22, 1992), and AD 75-17-04,
Amendment 39-3185 (43 FR 16151, April 17, 1978)

    Lynden suggested that we revise the proposed compliance times in
the proposed AD (72 FR 64005, November 14, 2007; corrected December 3,
2007 (72 FR 67998)), in light of two related existing ADs, to avoid
duplicative or contradictory results.
    AD 92-10-14, Amendment 39-8249 (57 FR 21727, April 22, 1992),
affects certain Lockheed Model 382 airplanes and addresses fatigue
cracking. That AD requires inspections at intervals not to exceed 3,600
flight hours, in accordance with SP-126 and SP-224. Lynden reported
being in compliance with that AD at its scheduled C check interval of
2,800 flight hours. The initial compliance times in the SSID are 1,800
flight hours for SP-126 and 3,600 flight hours for SP-224.

    AD 75-17-04, Amendment 39-2300 (40 FR 32827, August 5, 1975), as
revised by Amendment 39-3185 (43 FR 16151, April 17, 1978), affects
certain Lockheed Model 382 series airplanes and addresses cracking on
main frames. That AD requires inspections at intervals not to exceed
the ``C check'' (which corresponds to 2,800 flight hours for Lynden),
in accordance with SP-95, which is required at intervals not to exceed
1,200 flight hours in accordance with the SSID. Lynden reported being
in compliance with AD 75-17-04 at 1,400-flight-hour intervals, at B-2
and C checks.
    We disagree that it is necessary to change the compliance times in
this AD. The inspection requirements of AD 92-10-14, Amendment 39-8249
(57 FR 21727, May 22, 1992); and AD 75-17-04, Amendment 39-3185 (43 FR
16151, April 17, 1978); as well as the other ADs identified in the
SSID, do not conflict with this AD. We have not changed the final rule
regarding this issue.

Request To Clarify Basis for SSID Inspections

    Lynden found no objective evidence that the inspections are based
on clear objective damage tolerance evaluations. Lynden noted that the
SSID was drawn from existing programs and the inspection areas were
validated by ``full scale fatigue test and service corrosion and
cracking data.'' Lynden added that the DAH understands that the
maintenance program must be based on FAA-approved DT-based structural
inspection procedures, but the fourth paragraph of Section 2.0
(Introduction) of the SSID reveals that the information is based only
in part on damage tolerance assessments.
    We infer that Lynden was requesting clarification of the basis for
the inspection procedures. The information in the SSID comes from
several sources. On affected airplanes, the DAH performed several full-
scale tests and has developed a large data bank of service history
(including SDRs) to identify problem areas and PSEs. A DTA was
performed to establish the inspection intervals after many of the PSEs
had already been identified. Initially, the fatigue test and service
history data were used only to identify the problem area PSEs to
receive DTA evaluation, and to validate the DTA data. Every PSE
received a DTA. As part of the assessment of each PSE, the DAH found
that in some instances the DTA did not correlate well with the fatigue
test and service life data. In those instances, the fatigue test and
service life data were used to establish the inspection intervals that
are presented in the SSID. We have not changed the final rule regarding
this issue.

Request To Clarify Use of Military Data as Basis for the SSID

    According to Sections 1.0 (Purpose) and 2.0 (Introduction) of the
SSID, data used by the DAH were based on information from military
usage. Lynden concluded that the FAA's evaluation of commercial usage
does not appear to be based on objective criteria or on information
submitted to the SDR database sufficient to determine whether the
``crack growth rate severity of typical commercial usage is similar to
the baseline military usage, particularly in wing lower surface
structure.'' Lynden found nothing in the AD docket indicating whether
the DAH or the FAA evaluated the findings of commercial operators.
    We agree that the SSID is based in part on military usage, which
was used to define the baseline inspection requirements. Recent
analysis of the usage data has shown that typical commercial operation
of the affected airplanes is at higher payloads than that of military
operations with significantly less time in training. Analysis and in-
service cracking data have also shown that the crack growth rate
severity of typical commercial usage is very similar to the baseline
military usage. Our evaluation of commercial usage is therefore based
on objective criteria and information submitted by operators. We have
not changed this final rule regarding this issue. The DAH has advised
that the recommended inspection intervals might be extended if
operators complete an OUE and request AMOC approval.

Request To Clarify SSID Basis

    Paragraph (g) of the proposed AD (72 FR 64005, November 14, 2007;
corrected December 3, 2007 (72 FR 67998)) would require incorporation
of a revision into the maintenance inspection program that provides no
less than the required damage-tolerance rating for each PSE listed in
the SSID. Lynden noted however that the SSID does not provide damage-
tolerance ratings (as published in Boeing SSIDs), and provides only
inspection intervals for SPs that are already part of the CAMP. And the
required reports have not been incorporated into the findings or
reassessment by the TC holder or FAA.
    We agree to provide clarification. Each manufacturer's SSID is
different. And each DAH has a different approach regarding collecting
the data, implementing the required inspection, and reporting the
results. Boeing used a damage tolerance rating procedure for its SSID
program; Lockheed chose a different method. We accept both methods. The
different oversight ACOs also have authority to approve whatever data
they deem necessary to meet the requirements of the AD, as long as the
data meet the intent of the FAA regulations, policies, and guidance
materials. We have determined that the SSID meets those requirements.
We have not changed the final rule regarding this issue.

Request To Clarify Purpose of Section 4.0 (Principle Structural
Elements) of the SSID

    Lynden stated that Section 4.0 (Principal Structural Elements) of
the SSID seems to be the list of PSEs required by the proposed AD (72
FR 64005, November 14, 2007; corrected December 3, 2007 (72 FR 67998)),
yet there is no specific reference to that section, and that section
does not contain the required DTA values.
    We agree to provide clarification. Section 4.0 (Principle
Structural Elements) of the SSID simply links the PSE number with a
description of the PSE. Section 4.0 (Principle Structural Elements)
identifies and defines the individual PSEs by zones of the airplane.
The required DTA values or inspection intervals are presented in
Section 6.0 (Structural Inspection Requirements) of the SSID. We have
not changed the final rule regarding this issue.

Request To Require Inspections in Service Bulletins Instead of SSID

    Lynden stated that the actions proposed in the proposed AD (72 FR
64005, November 14, 2007; corrected December 3, 2007 (72 FR 67998))
would increase recordkeeping complexity without equally enhancing
safety. Since the SP cards listed in the SSID are already a mandatory
part of the CAMP, Lynden requested that we issue an AD that requires
accomplishment of the specific structural service bulletins already
issued by the TC holder and incorporated into Lynden's inspection
program, instead of the SSID inspections. Lynden suggested this as a
better, less complex method of ensuring continued structural integrity.
    We disagree with the request. Any operator with a CAMP is already
in compliance with the SSID, except for the minor changes noted
previously. Furthermore, mandating accomplishment of those service
bulletins would necessitate issuing a supplemental NPRM to provide the
opportunity for the public to comment on the merits of this change, and
would further delay issuance of this AD,

without increasing safety. Operators doing the inspection program are
required to set up a tracking system for each inspection and maintain
that system at all times, so very little additional work for
recordkeeping should be required. The operator and the FAA can track
the status of the inspections by inspection numbers assigned to each
inspection requirement by the operator, or by the procedure and card
number defined by the SSID, or by any other procedure approved by the
FAA. We have not changed the final rule regarding this issue.

Request To Revise Reporting Requirement

    Lynden asserted that the proposed reporting requirement of the
proposed AD (72 FR 64005, November 14, 2007; corrected December 3, 2007
(72 FR 67998)) (as specified in Section 7.0 (Discrepancy Reporting) of
the SSID) is unnecessary and burdensome, because operators must also
file SDRs for all structural defects. Lynden stated that submitting the
SDRs to the TC holder would comply with the proposed reporting
requirements of the proposed AD, since the TC holder could simply query
the FAA's SDR database and obtain the same information. To eliminate
the need to develop two different reporting systems to comply with both
reporting requirements, Lynden requested that we revise the proposed AD
to either (1) specify that operators do not need to report to the TC
holder if the report is made under the SDR requirements, or (2) match
the proposed AD language to the specifications of the SDR.
    We partially agree. Most of the information required by the SSID
will be identical to the SDRs except for some minor changes. The
results reported for the SSID inspections may be used for the SDRs (if
the reports include all the information required as specified in the
SDR reporting procedures), and the SDRs may be used for the SSID
inspections. But to simplify the reporting requirements, one report may
be used for both the SDR and the AD. We have revised paragraph (g) in
this final rule to include this provision.

Request To Address Cracking Found During Non-SSID Inspections

    Lynden requested that we clarify whether cracks found in SSID-
specific PSEs fall under the scope of the proposed AD (72 FR 64005,
November 14, 2007; corrected December 3, 2007 (72 FR 67998)), including
repairing and reporting cracks found in SSID-specific PSEs during a
non-SSID inspection.
    We agree that clarification is necessary. All cracks found during a
SSID inspection are covered by the SSIP reporting procedures. Cracks in
a PSE found outside a SSID inspection are not part of the SSID
reporting but do fall under the Aging Airplane Safety Rule (70 FR 5518,
February 2, 2005) (Docket FAA-1999-5401) reporting so they will still
need to be reported. The reporting procedures should be the same. We
have not changed the final rule regarding this issue.

Request To Allow Future SSID Changes in AD

    Lynden stated that, according to Section 1.0 (Purpose) of the SSID,
Lockheed Martin will provide operators with a method to comply with
section 121.1109 of the Federal Aviation Regulations (14 CFR 121.1109),
which allows for continual adjustments to (1) account for changes in
the product materials, parts, and processes; and (2) issue new or
improved repairs and revisions of the structural repair manual and
service bulletins. Lynden noted that changing an AD requires additional
time and resources of the operator, the DAH, and the FAA.
    We infer that Lynden was requesting that we revise the proposed AD
(72 FR 64005, November 14, 2007; corrected December 3, 2007 (72 FR
67998)) to allow for unspecified adjustments to the requirements. We
disagree. All changes to the SSID must be approved by the Atlanta ACO.
We would consider superseding the AD only when significant changes to
the SSID affect the airworthiness of the affected airplanes. The only
requirements are those specified in the AD--in this case, the specific
revision to the SSID. An operator wishing to use any changes in a
future revision to the SSID (not mandated by the AD) must request AMOC
approval in accordance with the provisions of paragraph (q) of this AD.
We have not changed this final rule regarding this issue.

Request for Access to ``Reference 2''

    Lynden alleged that the ``initial flaw criteria'' specified in
Section 5.2 of the SSID are based on assumptions unknown to Lynden. The
SSID states that the initial flaw size and flaw shape assumptions as
well as the structural flaw configuration used in the DTA of crack
growth are based on the assumptions determined in ``Reference 2,'' as
specified in that paragraph. Because ``Reference 2'' is reserved and
therefore unidentified, Lynden asserted that it could not review or
confirm the methodology. Lynden requested access to all information
used to establish compliance with the proposed AD (72 FR 64005,
November 14, 2007; corrected December 3, 2007 (72 FR 67998)) to make
substantive comment to the docket.
    We disagree that access to ``Reference 2'' is necessary. We have
reviewed ``Reference 2'' and approved the ``initial flaw criteria.''
The information in ``Reference 2'' is the DAH's proprietary data, and
the FAA cannot release this information to operators. We have
determined that operators do not need this information to accomplish
the SSID requirements. We accept the DAH's initial flaw size and flaw
shape assumptions as well as the structural flow configuration used in
the DTA of crack growth presented in ``Reference 2.'' We have not
changed the final rule regarding this issue.

Request To Clarify DAH's Involvement in SSID

    Lynden interpreted Section 1.0 (Purpose) of the SSID as suggesting
that the DAH anticipated an AD but did not expect it to be based on its
ever-changing SSID document. Lynden added that the DAH did not
understand that, after the AD is issued, the SSID requirements cannot
be changed unless the operator obtains an AMOC or the FAA supersedes
the AD. Lynden also asserted that the first paragraph of Section 2.0
(Introduction) of the SSID clearly establishes that the DAH did not
understand or appreciate how its SSID document would be used as the
basis for an AD.
    We disagree with Lynden's assertions. The DAH understands how its
SSID will be used as the basis for the AD. The DAH also understands
that the FAA must either supersede the AD to incorporate any
significant changes to the SSID, or approve AMOCs to make any changes
to SSID procedures or compliance times that are not specifically
required by the AD. We have not changed the final rule regarding this
issue.

Request To Identify Section 6.0 (Structural Inspection Requirements) of
SSID

    The proposed AD (72 FR 64005, November 14, 2007; corrected December
3, 2007 (72 FR 67998)) proposed implementing the requirements of
Section 5.0 (Damage Tolerance Analysis Methodology) and Section 7.0
(Discrepancy Reporting) of the SSID, but LM Aero suggested that the
most important requirements are in Section 6.0 (Structural Inspection
Requirements). Section 6.0 (Structural Inspection Requirements)
contains the references for the required inspection

procedures as well as the compliance times for the initial and
repetitive inspections. LM Aero stated that implementing the Section
6.0 (Structural Inspection Requirements) requirements will meet the DTA
methodology requirements contained in Section 5.0 (Damage Tolerance
Analysis Methodology). LM Aero agreed with the proposed requirement to
comply with Section 7.0 (Discrepancy Reporting). Lynden concurred with
this comment.
    We agree with LM Aero's position. We have revised paragraph (g) in
this final rule to include Sections 5.0 (Damage Tolerance Analysis
Methodology), 6.0 (Structural Inspection Requirements), and 7.0
(Discrepancy Reporting) of the SSID.

Request To Provide Terminating Action

    Lynden noted that the SSID, on page 6-12 in Section 6.0 (Structural
Inspection Requirements), requires accomplishment of a certain
inspection initially by 12,000 total flight hours, with recurring
inspections due at intervals not to exceed 2,400 flight hours
thereafter. Lynden requested that the SSID or the proposed AD (72 FR
64005, November 14, 2007; corrected December 3, 2007 (72 FR 67998)) be
revised to state that accomplishment of Lockheed Service Bulletin 382-
71-24, dated January 21, 2010, eliminates the need for this recurring
inspection requirement.
    We disagree with the request to allow accomplishment of Lockheed
Service Bulletin 382-71-24, dated January 21, 2010, as terminating
action for the specified inspection requirement. Lockheed Service
Bulletin 382-71-24, dated January 21, 2010, was never approved by the
Atlanta ACO as terminating action. But replacing the bushing and
repairing existing damage per Lockheed Service Bulletin 382-71-24,
dated January 21, 2010, will allow operators to zero out the time for
the inspection. Operators may request an AMOC for relief from this
requirement in accordance with the provisions of paragraph (q) of this
AD, provided data are provided that show that accomplishment of
Lockheed Service Bulletin 382-71-24, dated January 21, 2010, would
provide an acceptable level of safety allowing for this terminating
action. Since not all operators have accomplished the actions specified
in Lockheed Service Bulletin 382-71-24, dated January 21, 2010, the
inspections must remain in the SSID. We have not changed the final rule
regarding this issue.

Request To Clarify Impact on Alaska Operations

    Lynden interpreted the Regulatory Evaluation for this action as
stating that the AD would have no impact on intrastate aviation in the
state of Alaska. Lynden reported that it moves over 82 million pounds
of cargo per year in Alaska, so the proposed AD (72 FR 64005, November
14, 2007; corrected December 3, 2007 (72 FR 67998)) would definitely
have an impact on those operations.
    We agree to provide clarification. The Regulatory Evaluation states
that the AD ``could affect intrastate aviation in Alaska,'' but adds
that it is not ``appropriate to include specific requirements for
aircraft operated in Alaska.'' This AD applies only to airplanes when
operated outside the territorial boundaries of Alaska. We have not
changed the final rule regarding this issue. Because of the nature of
the unsafe condition, we cannot justify a regulatory distinction
between aviation only in Alaska and other aviation.

Request To Account for Widespread Fatigue Damage (WFD) Rulemaking

    Lynden was concerned about the pending rulemaking related to WFD to
propose certain changes to the requirements for evaluating structure,
assigning inspections, and doing other maintenance or alteration tasks.
    Lynden made no specific request. The SSIP does not account for the
effects of WFD. We have not changed the final rule regarding this
issue.

Additional Changes Made to This AD

    We have revised this final rule to identify the legal name of the
manufacturer as published in the most recent type certificate data
sheet for the affected airplane models.
    We have added new paragraph (e) in this final rule to provide ATA
subject code 51: Standard practices/structures. This code is added to
make this final rule parallel with other new AD actions. We have re-
identified subsequent paragraphs accordingly.
    We have revised paragraph (g) of this AD to remove the phrase
``FAA-approved'' from ``FAA-approved maintenance inspection program,''
because we do not approve operators' maintenance programs.
    We have removed the ``Service Information'' paragraph from this
final rule. (That paragraph was identified as paragraph (f) in the
proposed AD (72 FR 64005, November 14, 2007; corrected December 3, 2007
(72 FR 67998)).) Instead, we have provided the full document citations
throughout this final rule.
    Since we issued the proposed AD (72 FR 64005, November 14, 2007;
corrected December 3, 2007 (72 FR 67998)), we have increased the labor
rate used in the Costs of Compliance from $80 per work-hour to $85 per
work-hour. The Costs of Compliance information, below, reflects this
increase in the specified labor rate.
    We have re-identified Note 3 of the proposed AD (72 FR 64005,
November 14, 2007; corrected December 3, 2007 (72 FR 67998)) as Note 1
of this final rule, and relocated that note to follow paragraph (g) of
this AD. We have reidentified subsequent notes accordingly.

Conclusion

    We reviewed the relevant data, considered the comments received,
and determined that air safety and the public interest require adopting
the AD with the changes described previously. We also determined that
these changes will not increase the economic burden on any operator or
increase the scope of the AD.

Costs of Compliance

    There are about 91 airplanes of the affected design in the
worldwide fleet. The following table provides the estimated costs for
the 14 U.S. airplanes to comply with this AD.

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                     Average labor
               Action                          Work hours            rate per hour            Fleet cost
----------------------------------------------------------------------------------------------------------------
Revision of maintenance inspection    600 for the fleet...........              $85  $51,000.
 program.
Inspections.........................  2,724 per airplane..........               85  $3,241,560, per inspection
                                                                                cycle.
----------------------------------------------------------------------------------------------------------------

    The number of inspection work hours, as indicated above, is
presented as if the accomplishment of the actions in this AD are to be
conducted as ``stand-alone'' actions. However, in actual practice,
these actions for the most part will be done coincidentally or in
combination with normally scheduled airplane inspections and other
maintenance program tasks. Therefore, the actual number of necessary
additional inspection work hours will be minimal in many instances.
Additionally, any costs associated with special airplane scheduling
will be minimal.
    Further, compliance with this AD is a means of compliance with the
aging airplane safety final rule (AASFR) for the baseline structure of
Model 382, 382B, 382E, 382F, and 382G series airplanes. The AASFR
requires certain operators to incorporate damage tolerance inspections
into their maintenance inspection programs. These requirements are
described in 14 CFR 121.370(a) and 129.16. Accomplishment of the
actions required by this AD will meet the requirements of these CFR
sections for the baseline structure. The costs for accomplishing the
inspection portion of this AD were accounted for in the regulatory
evaluation of the AASFR.

Authority for This Rulemaking

    Title 49 of the United States Code specifies the FAA's authority to
issue rules on aviation safety. Subtitle I, section 106, describes the
authority of the FAA Administrator. Subtitle VII: Aviation Programs,
describes in more detail the scope of the Agency's authority.
    We are issuing this rulemaking under the authority described in
Subtitle VII, Part A, Subpart III, Section 44701: ``General
requirements.'' Under that section, Congress charges the FAA with
promoting safe flight of civil aircraft in air commerce by prescribing
regulations for practices, methods, and procedures the Administrator
finds necessary for safety in air commerce. This regulation is within
the scope of that authority because it addresses an unsafe condition
that is likely to exist or develop on products identified in this
rulemaking action.

Regulatory Findings

    This AD will not have federalism implications under Executive Order
13132. This AD will not have a substantial direct effect on the States,
on the relationship between the national government and the States, or
on the distribution of power and responsibilities among the various
levels of government.
    For the reasons discussed above, I certify that this AD:
    (1) Is not a ``significant regulatory action'' under Executive
Order 12866,
    (2) Is not a ``significant rule'' under DOT Regulatory Policies and
Procedures (44 FR 11034, February 26, 1979),
    (3) Will not affect intrastate aviation in Alaska, and
    (4) 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.

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:

PART 39--AIRWORTHINESS DIRECTIVES

0
1. The authority citation for part 39 continues to read as follows:

    Authority: 49 U.S.C. 106(g), 40113, 44701.

Sec.  39.13  [Amended]

0
2. The FAA amends Sec.  39.13 by adding the following new airworthiness
directive (AD):

2012-06-09 Lockheed Martin Corporation/Lockheed Martin Aeronautics
Company: Amendment 39-16990. Docket No. FAA-2007-0109; Directorate
Identifier 2007-NM-235-AD.

(a) Effective Date

    This AD is effective May 15, 2012.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to all Lockheed Martin Corporation/Lockheed
Martin Aeronautics Company Model 382, 382B, 382E, 382F, and 382G
airplanes, certificated in any category.

(d) Unsafe Condition

    This AD results from a report of incidents involving fatigue
cracking and corrosion in transport category airplanes that are
approaching or have exceeded their design service objective. We are
issuing this AD to maintain the continued structural integrity of
the fleet.

(e) Subject

    Air Transport Association (ATA) of America Code 51: Standard
Practices/Structures.

(f) Compliance

    You are responsible for having the actions required by this AD
performed within the compliance times specified, unless the actions
have already been done.

(g) Revision of the Maintenance Inspection Program

    Within 12 months after the effective date of this AD,
incorporate a revision into the maintenance inspection program that
provides no less than the required damage tolerance assessment/
analysis (DTA) for each structural significant item (SSI) listed in
Lockheed Martin Model 382, 382B, 382E, 382F, and 382G Series
Aircraft Service Manual Publication (SMP), Supplemental Structural
Inspection Document (SSID), SMP 515-C-SSID, Change 1, dated
September 10, 2007. (The required inspection interval for each
principal structural element (PSE) is listed in Lockheed Martin
Model 382, 382B, 382E, 382F, and 382G Series Aircraft Service Manual
Publication (SMP), Supplemental Structural Inspection Document
(SSID), SMP 515-C-SSID, Change 1, dated September 10, 2007.) The
revision to the maintenance inspection program must include and must
be implemented in accordance with the procedures in Section 5.0
(Damage Tolerance Analysis Methodology), Section 6.0 (Structural
Inspection Requirements), and Section 7.0 (Discrepancy Reporting) of
Lockheed Martin Model 382, 382B, 382E, 382F, and 382G Series
Aircraft Service Manual Publication (SMP), Supplemental Structural
Inspection Document (SSID), SMP 515-C-SSID, Change 1, dated
September 10, 2007. One report may be used to report findings for
both the service difficulty report and this AD, provided the report
refers to this AD and the PSE number for the inspection being
accomplished when the discrepancy was found.
    Note 1 to paragraphs (g) through (p) of this AD: Compliance with
the requirements of this AD establishes compliance with section
121.1109(c)(1) of the Federal Aviation Regulations (14 CFR
121.1109(c)(1)).

 (h) Paperwork Reduction Act Burden Statement

    A federal agency may not conduct or sponsor, and a person is not
required to respond to, nor shall a person be subject to a penalty
for failure to comply with a collection of information subject to
the requirements of the Paperwork Reduction Act unless that
collection of information displays a current valid OMB Control
Number. The OMB Control Number for this information collection is
2120-0056. Public reporting for this collection of information is
estimated to be approximately 5 minutes per response, including the
time for reviewing instructions, completing and reviewing the
collection of information. All responses to this collection of
information are mandatory. Comments concerning the accuracy of this
burden and suggestions for reducing the burden should be directed to
the FAA at: 800 Independence Ave. SW., Washington, DC 20591, Attn:
Information Collection Clearance Officer, AES-200.

(i) Initial and Repetitive Inspections

    At the later of the times specified in paragraphs (i)(1) and
(i)(2) of this AD, except as provided by paragraphs (j) through (n)
of this AD: Do the applicable initial inspections to detect cracks
of all SSIs, in accordance with Lockheed Martin Model 382, 382B,
382E, 382F, and 382G Series Aircraft Service Manual Publication
(SMP), Supplemental Structural Inspection Document (SSID), SMP 515-
C-SSID, Change 1, dated September 10, 2007. Repeat the applicable
inspections thereafter at intervals not to exceed the ``Recurring''
intervals specified in Section 6.0 (Structural Inspection
Requirements) of Lockheed Martin Model 382, 382B, 382E, 382F, and
382G Series Aircraft Service Manual Publication (SMP), Supplemental
Structural Inspection Document (SSID), SMP 515-C-SSID, Change 1,
dated September 10, 2007, except as provided by paragraphs (l)
through (n) of this AD.
    (1) Before the applicable ``Initial'' threshold specified in
Section 6.0 (Structural Inspection Requirements) of Lockheed Martin
Model 382, 382B, 382E, 382F, and 382G Series Aircraft Service Manual
Publication (SMP), Supplemental Structural Inspection Document
(SSID), SMP 515-C-SSID, Change 1, dated September 10, 2007.
    (2) Within 36 months after the effective date of this AD, or
within one ``Recurring'' interval measured from 12 months after the
effective date of the AD, whichever comes first.

(j) Exception to Service Information Compliance Time (Threshold Since
New)

    Where Section 6.0 (Structural Inspection Requirements) of
Lockheed Martin Model 382, 382B, 382E, 382F, and 382G Series
Aircraft Service Manual Publication (SMP), Supplemental Structural
Inspection Document (SSID), SMP 515-C-SSID, Change 1, dated
September 10, 2007, specifies the ``Initial'' threshold in years
(since new), this AD requires compliance within the specified year
since the date of issuance of the original standard airworthiness
certificate or the date of issuance of the original export
certificate of airworthiness.

(k) Exception to Service Information Compliance Time (Special
Condition)

    Where Section 6.0 (Structural Inspection Requirements) of
Lockheed Martin Model 382, 382B, 382E, 382F, and 382G Series
Aircraft Service Manual Publication (SMP), Supplemental Structural
Inspection Document (SSID), SMP 515-C-SSID, Change 1, dated
September 10, 2007, specifies the ``Initial'' threshold as ``Special
Condition,'' this AD requires compliance within 24 months after the
effective date of this AD.

(l) Exception to Service Information Compliance Time (Fuselage Station
(FS) 1041 Fitting Replacement)

    Where Section 6.0 (Structural Inspection Requirements) of
Lockheed Martin Model 382, 382B, 382E, 382F, and 382G Series
Aircraft Service Manual Publication (SMP), Supplemental Structural
Inspection Document (SSID), SMP 515-C-SSID, Change 1, dated
September 10, 2007, specifies the ``Initial'' threshold and
``Recurring'' interval as ``FS 1041 Fitting Replacement,'' this AD
requires compliance within 24 months after the effective date of
this AD and thereafter at intervals not to exceed those specified in
Lockheed Martin Model 382, 382B, 382E, 382F, and 382G Series
Aircraft Service Manual Publication (SMP), Supplemental Structural
Inspection Document (SSID), SMP 515-C-SSID, Change 1, dated
September 10, 2007, concurrently with any FS 1041 fitting
replacement.

(m) Exception to Service Information Compliance Time (Engine Change)

    Where Section 6.0 (Structural Inspection Requirements) of
Lockheed Martin Model 382, 382B, 382E, 382F, and 382G Series
Aircraft Service Manual Publication (SMP), Supplemental Structural
Inspection Document (SSID), SMP 515-C-SSID, Change 1, dated
September 10, 2007, specifies the ``Initial'' threshold and
``Recurring'' interval as ``Engine Change,'' this AD requires
compliance before further flight after the next engine change, and
thereafter before further flight whenever the engines are changed.

(n) Exception to Service Information Compliance Time (Aft Lord Mount
Change)

    Where Section 6.0 (Structural Inspection Requirements) of
Lockheed Martin Model 382, 382B, 382E, 382F, and 382G Series
Aircraft Service Manual Publication (SMP), Supplemental Structural
Inspection Document (SSID), SMP 515-C-SSID, Change 1, dated
September 10, 2007, specifies the ``Initial'' threshold and
``Recurring'' interval as ``Aft Lord Mount Change,'' this AD
requires compliance before further flight after the next aft lord
mount change (FS 1041 fitting change), and thereafter at intervals
not to exceed those specified in Lockheed Martin Model 382, 382B,
382E, 382F, and 382G Series Aircraft Service Manual Publication
(SMP), Supplemental Structural Inspection Document (SSID), SMP 515-
C-SSID, Change 1, dated September 10, 2007, concurrently with any FS
1041 fitting replacement.

(o) Repair

    If any cracked structure is found during the inspections
required by paragraph (i) of this AD, before further flight, repair
the cracked structure using a method approved by the Manager,
Atlanta Aircraft Certification Office (ACO), FAA. For a repair
method to be approved by the Manager, Atlanta ACO, as required by
this paragraph, the Manager's approval letter must specifically
refer to this AD.
    Note 2 to paragraph (o) of this AD: Applicable existing FAA-
approved repair procedures do not require further approval provided
they have DTA-established inspection procedures and intervals
previously approved by the FAA.
    Note 3 to paragraph (o) of this AD: Operators may contact the
Manager, Atlanta ACO, for information regarding the use of published
service data approved by the FAA associated with the repairs
specified in paragraph (o) of this AD.

(p) Inspection Program for Transferred Airplanes

    Before any airplane that is subject to this AD and that has
exceeded the applicable compliance times specified in paragraph (i)
of this AD can be added to an air carrier's operations
specifications, a program for the accomplishment of the inspections
required by this AD must be established in accordance with paragraph
(p)(1) or (p)(2) of this AD, as applicable.
    (1) For airplanes that have been inspected in accordance with
this AD: The inspection of each PSE must be done by the new operator
in accordance with the previous operator's schedule and inspection
method, or the new operator's schedule and inspection method, at
whichever time would result in the earlier accomplishment for that
PSE inspection. The compliance time for accomplishment of this
inspection must be measured from the last inspection accomplished by
the previous operator. After each inspection has been done once,
each subsequent inspection must be performed in accordance with the
new operator's schedule and inspection method.
    (2) For airplanes that have not been inspected in accordance
with this AD: The inspection of each PSE required by this AD must be
done either before adding the airplane to the air carrier's
operations specification, or in accordance with a schedule and an
inspection method approved by the Manager, Atlanta ACO. After each
inspection has been done once, each subsequent inspection must be
done in accordance with the new operator's schedule.

 (q) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, Atlanta ACO, has the authority to approve AMOCs
for this AD, if requested in accordance with the procedures found in
14 CFR 39.19. In accordance with 14 CFR 39.19, send your request to
your principal inspector or local Flight Standards District Office,
as appropriate. If sending information directly to the manager of
the ACO, send it to the attention of the person identified in the
Related Information section of this AD.
    (2) Before using any approved AMOC, notify your appropriate
principal inspector, or lacking a principal inspector, the manager
of the local flight standards district office/certificate holding
district office.

(r) Related Information

    For more information about this AD, contact Carl Gray, Aerospace
Engineer, Airframe Branch, ACE-117A, FAA, Atlanta Aircraft
Certification Office, 1701 Columbia Avenue, College Park, Atlanta,
Georgia 30337; phone:<PHONE_NUMBER>; fax:<PHONE_NUMBER>; email:
<EMAIL_ADDRESS>
(s) Material Incorporated by Reference

    (1) You must use the following service information to do the
actions required by this AD, unless the AD specifies otherwise. The
Director of the Federal Register approved the incorporation by
reference (IBR) of the following service information under 5 U.S.C.
552(a) and 1 CFR part 51:
    (i) Lockheed Martin Model 382, 382B, 382E, 382F, and 382G Series
Aircraft Service Manual Publication (SMP), Supplemental Structural
Inspection Document (SSID), SMP 515-C-SSID, Change 1, dated
September 10, 2007.

    (2) For service information identified in this AD, contact
Lockheed Martin Corporation/Lockheed Martin Aeronautics Company,
Airworthiness Office, Dept. 6A0M, Zone 0252, Column P-58, 86 S. Cobb
Drive, Marietta, Georgia 30063; telephone<PHONE_NUMBER>; fax 770-494-
5445; email<EMAIL_ADDRESS>Internet http://www.lockheedmartin.com/ams/tools/TechPubs.html.
    (3) You may review copies of the service information at the FAA,
Transport Airplane Directorate, 1601 Lind Avenue SW., Renton,
Washington. For information on the availability of this material at
the FAA, call<PHONE_NUMBER>.
    (4) You may also review copies of the service information that
is incorporated by reference at the National Archives and Records
Administration (NARA). For information on the availability of this
material at an NARA facility, call<PHONE_NUMBER>, or go to http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html.

    Issued in Renton, Washington, on March 12, 2012.
John P. Piccola,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 2012-8450 Filed 4-9-12; 8:45 am]
BILLING CODE 4910-13-P