

[Federal Register: February 5, 2008 (Volume 73, Number 24)]
[Proposed Rules]               
[Page 6622-6627]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr05fe08-21]                         

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2008-0123; Directorate Identifier 2007-NM-056-AD]
RIN 2120-AA64

 
Airworthiness Directives; McDonnell Douglas Model DC-8-11, DC-8-
12, DC-8-21, DC-8-31, DC-8-32, DC-8-33, DC-8-41, DC-8-42, and DC-8-43 
Airplanes; Model DC-8-51, DC-8-52, DC-8-53, and DC-8-55 Airplanes; 
Model DC-8F-54 and DC-8F-55 Airplanes; Model DC-8-61, DC-8-62, and DC-
8-63 Airplanes; Model DC-8-61F, DC-8-62F, and DC-8-63F Airplanes; Model 
DC-8-71, DC-8-72, and DC-8-73 Airplanes; and Model DC-8-71F, DC-8-72F, 
and DC-8-73F Airplanes

AGENCY: Federal Aviation Administration (FAA), Department of 
Transportation (DOT).

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: The FAA proposes to supersede an existing airworthiness 
directive (AD) that applies to McDonnell Douglas Model DC-8 airplanes. 
The existing AD currently requires, among other things, revision of an 
existing program of structural inspections. This proposed AD would 
require implementation of a program of structural inspections of 
baseline structure to detect and correct fatigue cracking in order to 
ensure the continued airworthiness of these airplanes as they approach 
the manufacturer's original fatigue design life goal. This proposed AD 
results from a significant number of these airplanes approaching or 
exceeding the design service goal on which the initial type 
certification approval was predicated. We are proposing this AD to 
detect and correct fatigue cracking that could compromise the 
structural integrity of these airplanes.

DATES: We must receive comments on this proposed AD by March 21, 2008.

ADDRESSES: You may send comments by any of the following methods:
     Federal eRulemaking Portal: Go to http://www.regulations.gov.
 Follow the instructions for submitting comments.

     Fax: 202-493-2251.
     Mail: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue, SE., Washington, DC 20590.
     Hand Delivery: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue, SE., Washington, DC 20590, between 9 a.m. and 5 p.m., 
Monday through Friday, except Federal holidays.
    For service information identified in this AD, contact Boeing 
Commercial Airplanes, Long Beach Division, 3855 Lakewood Boulevard, 
Long Beach, California 90846, Attention: Data and Service Management, 
Dept. C1-L5A (D800-0024).

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 proposed AD, the regulatory 
evaluation, any comments received, and other information. The street 
address for the Docket Office (telephone 800-647-5527) is in the 
ADDRESSES section. Comments will be available in the AD docket shortly 
after receipt.

FOR FURTHER INFORMATION CONTACT: Jon Mowery, Aerospace Engineer, 
Airframe Branch, ANM-120L, FAA, Los Angeles Aircraft Certification 
Office, 3960 Paramount Boulevard, Lakewood, California 90712-4137; 
telephone (562) 627-5322; fax (562) 627-5210.

SUPPLEMENTARY INFORMATION: 

Comments Invited

    We invite you to send any written relevant data, views, or 
arguments about this proposed AD. Send your comments to an address 
listed under the ADDRESSES section. Include ``Docket No. FAA-2008-0123; 
Directorate Identifier 2007-NM-056-AD'' at the beginning of your 
comments. We specifically invite comments on the overall regulatory, 
economic, environmental, and energy aspects of this proposed AD. We 
will consider all comments received by the closing date and may amend 
this proposed AD because of those comments.
    We will post all comments we receive, without change, to http://www.regulations.gov
, including any personal information you provide. We 

will also post a report summarizing each substantive verbal contact we 
receive about this proposed AD.

Discussion

    On January 11, 1993, we issued AD 93-01-15, amendment 39-8469 (58 
FR 5576, January 22, 1993), for McDonnell Douglas Model DC-8 airplanes. 
That AD requires structural inspections to detect fatigue cracking, 
reporting of the inspection results, and repair, as

[[Page 6623]]

necessary, to ensure continued airworthiness as these airplanes 
approach the manufacturer's original fatigue design life goal. That AD 
resulted from new data submitted by the manufacturer indicating that 
additional inspections and an expanded sample size are necessary to 
increase the confidence level of the statistical program to ensure 
timely detection of cracks in the principal structural elements (PSEs). 
We issued that AD to prevent fatigue cracking, which could result in a 
compromise of the structural integrity of these airplanes.

Supplemental Inspection Documents (SIDs) ADs

    In the early 1980s, as part of our continuing work to maintain the 
structural integrity of older transport category airplanes, we 
concluded that the incidence of fatigue cracking may increase as these 
airplanes reach or exceed their design service goal (DSG). A 
significant number of these airplanes were approaching or had exceeded 
the DSG on which the initial type certification approval was 
predicated. In light of this, and as a result of increased utilization, 
longer operational lives, and the high levels of safety expected of the 
currently operated transport category airplanes, we determined that a 
supplemental structural inspection program (SSIP) was necessary to 
ensure a high level of structural integrity for all airplanes in the 
transport fleet.

Issuance of Advisory Circular (AC)

    As a follow-on from that determination, we issued AC No. 91-56, 
``Supplemental Structural Inspection Program for Large Transport 
Category Airplanes,'' dated May 6, 1981. That AC provides guidance 
material to manufacturers and operators for use in developing a 
continuing structural integrity program to ensure safe operation of 
older airplanes throughout their operational lives. This guidance 
material applies to transport airplanes that were certified under the 
fail-safe requirements of part 4b (``Airplane Airworthiness, Transport 
Categories'') of the Civil Air Regulations of the Federal Aviation 
Regulations (FAR) (14 CFR part 25), and that have a maximum gross 
weight greater than 75,000 pounds. The procedures set forth in that AC 
are applicable to transport category airplanes operated under subpart D 
(``Special Flight Operations'') of part 91 of the FAR (14 CFR part 91); 
part 121 (``Operating Requirements: Domestic, Flag, and Supplemental 
Operations''); part 125 (``Certification and Operations: Airplanes 
having a Seating Capacity of 20 or More Passengers or a Maximum Payload 
of 6,000 Pounds or More''); and part 135 (``Operating Requirements: 
Commuter and On-Demand Operations'') of the FAR (14 CFR parts 121, 125, 
and 135). The objective of the SSIP was to establish inspection 
programs to ensure timely detection of fatigue cracking.

Aging Aircraft Safety Act (AASA)

    In October 1991, Congress enacted Title IV of Public Law 102-143, 
the AASA of 1991, to address aging aircraft concerns. That Act 
instructed the FAA administrator to prescribe regulations that will 
ensure the continuing airworthiness of aging aircraft.

FAA Responses To AASA

    On January 25, 2005, as one of the responses to the AASA, we issued 
the Aging Airplane Safety; Final Rule (AASFR) (70 FR 5518, February 2, 
2005). The AASFR applies to certain transport category, turbine powered 
airplanes with a type certificate issued after January 1, 1958 
(including the airplanes that would be subject to this proposed AD), 
that are operated under 14 CFR parts 121 or 129, with the exception of 
airplanes operated within the State of Alaska. Sections 121.370a and 
129.16 of the AASFR require the maintenance programs of those airplanes 
to include damage tolerance-based inspections and procedures for 
structure that is susceptible to fatigue cracking that could contribute 
to a catastrophic failure. The inspections and procedures must take 
into account the adverse affects that RAMs may have on fatigue cracking 
and the inspection of the structure. The procedures are to be 
established and incorporated before December 20, 2010. Compliance with 
this proposed AD also would be compliance with some aspects of the 
AASFR.

Relevant Service Information

    We have reviewed Boeing Report No. L26-011, ``DC-8 All Series 
Supplemental Inspection Document (SID),'' Volume I, Revision 6, dated 
July 2005 (hereafter ``Revision 6''). The purpose of Revision 6 is to 
define the mandatory inspection requirements for the PSEs and to 
provide specific non-destructive inspection (NDI) techniques and 
procedures for each PSE. Revision 6 also revises the maintenance 
program by removing provisions for the sampling inspection program. 
However, Revision 6 retains the program goal to inspect airplanes in 
advance of a certain threshold for the possibility of increasing that 
threshold and using service history to justify delaying inspections on 
the younger portion of the fleet. As with previous revisions, Revision 
6 provides credit for inspections previously accomplished within the 
required intervals. Revision 6 provides a description of PSEs, NDI 
locations, planning and reporting procedures, and certain criteria upon 
which the supplemental inspection program is based.
    We also have reviewed McDonnell Douglas Report No. L26-011, ``DC-8 
Supplemental Inspection Document (SID),'' Volume II, Revision 8, dated 
January 2005. This document describes specific non-destructive testing 
inspections of the SID, and has been approved as an acceptable 
alternative method of compliance with corresponding paragraphs of AD 
93-01-15.
    Accomplishing the actions specified in the service information 
described above is intended to adequately address the unsafe condition.

FAA's Determination and Requirements of the Proposed AD

    We have evaluated all pertinent information and identified an 
unsafe condition that is likely to exist or develop on other products 
of this same type design. This proposed AD would retain certain 
requirements of AD 93-01-15. This proposed AD also would require 
revision of the FAA-approved maintenance program. This proposed AD 
would require implementation of a structural inspection program of 
baseline structure to detect and correct fatigue cracking in order to 
ensure the continued airworthiness of airplanes as they approach the 
manufacturer's original fatigue design life goal. For the purposes of 
this proposed AD, a PSE is defined as an element that contributes 
significantly to the carrying of flight, ground or pressurization 
loads, and the integrity of that element is essential in maintaining 
the overall structural integrity of the airplane.
    The following paragraphs summarize certain specific actions in this 
proposed AD:
    Paragraph (h) of the proposed AD would require a revision of the 
maintenance inspection program that provides for inspection(s) of the 
PSE in accordance with Boeing Report No. L26-011, ``DC-8 Supplemental 
Inspection Document (SID),'' Volume I, Revision 6, dated July 2005. 
PSEs are also defined and specified in the SID.
    Paragraph (i) of the proposed AD would specify that the SID be 
implemented on a PSE-by-PSE basis before structure exceeds its 75% 
fatigue life threshold (\3/4\NTH) and its full fatigue life 
threshold (NTH). The threshold value is defined as the life 
of the

[[Page 6624]]

structure measured in total landings, when the probability of failure 
reaches one in a billion. The DC-8 SID program is not a sampling 
program. Airplanes would be inspected once before reaching both PSE 
thresholds (once by \3/4\NTH and once by NTH). In 
order for the inspection to have value, no PSE would be inspected 
before half of the fatigue life threshold, \1/2\NTH. The 
additional \3/4\NTH threshold aids in advancing the 
threshold for some PSEs as explained in Section 4 of Volume I of the 
SID. Inspection of each PSE should be done in accordance with the NDI 
procedures set forth in Volume II of the SID.
    For airplanes past the threshold NTH, the proposed AD 
would require that the PSE be inspected at repetitive intervals not to 
exceed [Delta]NDI/2 as specified in Section 4 of Volume I of the SID 
per the NDI procedure, which is specified in Volume II of the SID. The 
definition of [Delta]NDI/2 is half of the life for a crack to grow from 
a given NDI detectable crack size to instability.
    Paragraph (i) of this proposed AD also would require, for airplanes 
that have exceeded the NTH, that each PSE be inspected 
within 18 months after the effective date of this AD. The entire PSE 
must be inspected regardless of whether or not it has been repaired, 
altered, or modified.
    Paragraph (j) of this proposed AD would require that, if any PSE is 
repaired, altered, or modified, it must be considered a ``discrepant 
finding.'' A discrepant PSE indicates that it could not be completely 
inspected because the NDI procedure could not be accomplished due to 
differences on the airplane from the NDI reference standard (i.e., 
RAMs). For any discrepancy (e.g., a PSE cannot be inspected as 
specified in Volume II of the SID or does not match rework, repair, or 
modification description in Volume I of the SID), this proposed AD 
would require that the discrepancy be inspected in accordance with a 
method approved by the FAA.
    Paragraph (k) of this proposed AD would require that all negative 
or positive findings of the inspection done in paragraph (i) of the AD 
be reported to Boeing at the times specified, and per instructions 
contained in Section 4 of Volume I of the SID.
    Paragraph (l) of this proposed AD would require that any cracked 
structure detected during any inspection required by paragraph (i) of 
this proposed AD be repaired before further flight. Additionally, 
paragraph (l) of this AD would require accomplishment of the actions as 
specified in paragraphs (l)(1), (l)(2), and (l)(3) of this proposed AD, 
at the times specified below.
    1. Within 18 months after repair, accomplish a damage tolerance 
assessment (DTA) that defines the threshold for inspection and submit 
the assessment for approval to the Manager, Los Angeles Aircraft 
Certification Office (ACO), FAA.
    2. Before reaching 75% of the threshold, submit the inspection 
methods and repetitive inspections intervals for the repair for 
approval by the Manager of the Los Angeles ACO.
    3. Before the threshold, the inspection method and repetitive 
inspection intervals are to be incorporated into the FAA-approved 
structural maintenance or inspection program for the airplane.
    For the purposes of this proposed AD, the FAA anticipates that 
submissions of the DTA of the repair, if acceptable, should be approved 
within six months after submission.
    Paragraph (m) of this proposed AD specifies the requirements of the 
inspection program for transferred airplanes. Before any airplane that 
is subject to this proposed AD can be added to an air carrier's 
operations specifications, a program for the accomplishment of the 
inspections required by this proposed AD must be established. Paragraph 
(m) of the proposed AD would require accomplishment of the following:
    1. For airplanes that have been inspected per this proposed AD: The 
inspection of each PSE must be done by the new operator per the 
previous operator's schedule and inspection method, or per the new 
operator's schedule and inspection method, at whichever time would 
result in the earlier accomplishment date for that PSE inspection. The 
compliance time for accomplishment of this inspection must be measured 
from the last inspection done by the previous operator. After each 
inspection has been done once, each subsequent inspection must be done 
per the new operator's schedule and inspection method.
    2. For airplanes that have not been inspected per this proposed AD: 
The inspection of each PSE must be done either before adding the 
airplane to the air carrier's operations specification, or per a 
schedule and an inspection method approved by the FAA. After each 
inspection has been performed once, each subsequent inspection must be 
done per the new operator's schedule.
    Accomplishment of these actions will ensure that: (1) An Operator's 
newly acquired airplanes comply with its SSIP before being operated; 
and (2) frequently transferred airplanes are not permitted to operate 
without accomplishment of the inspections defined in the SID.
    Paragraph (n) of this proposed AD specifies that repairs and 
inspection/replacement programs done before the effective date in 
accordance with McDonnell Douglas Report No. MDC 91K0262, ``DC-8 Aging 
Aircraft Repair Assessment Program Document,'' Revision 1, dated 
October 2000; are acceptable for compliance with the requirements of 
paragraphs (g) and (l) of this proposed AD.

Differences Between the Proposed AD and the SID

    The SID specifies to contact the manufacturer for instructions on 
how to repair certain conditions, but this proposed AD would require 
repairing those conditions in one of the following ways:
     Using a method that we approve; or
     Using data that meet the certification basis of the 
airplane, and that have been approved by an Authorized Representative 
for the Boeing Commercial Airplanes Delegation Option Authorization 
Organization whom we have authorized to make those findings.

Change to Existing AD

    This proposed AD would retain all requirements of AD 93-01-15. 
Since AD 93-01-15 was issued, the AD format has been revised, and 
certain paragraphs have been rearranged. As a result, the corresponding 
paragraph identifiers have changed in this proposed AD, as listed in 
the following table:

                      Revised Paragraph Identifiers
------------------------------------------------------------------------
                                            Corresponding requirement in
        Requirement in AD 93-01-15                this proposed AD
------------------------------------------------------------------------
paragraph (b).............................  paragraph (f).
paragraph (c).............................  paragraph (g).
------------------------------------------------------------------------

Costs of Compliance

    There are about 194 airplanes of the affected design in the 
worldwide fleet. The following table provides the estimated costs for 
U.S. operators to comply with this proposed AD.

[[Page 6625]]



                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                                  Number of U.S.-
            Action                 Work hours      Average labor     Cost per       registered      Fleet cost
                                                   rate per hour     operator        airplanes
----------------------------------------------------------------------------------------------------------------
Revision of maintenance         544 per operator             $80         $43,520             131        $739,840
 inspection program (required    (17 U.S.
 by AD 93-01-15).                operators).
Revision of maintenance         250 per operator              80          20,000             131         340,000
 program and inspections (new    (17 U.S.
 proposed actions).              operators).
----------------------------------------------------------------------------------------------------------------

    The number of inspection work hours, as indicated above, is 
presented as if the accomplishment of the actions in this proposed AD 
is 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.

Authority for This Rulemaking

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

Regulatory Findings

    We have determined that this proposed AD would not have federalism 
implications under Executive Order 13132. This proposed AD would 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 the proposed 
regulation:
    1. Is not a ``significant regulatory action'' under Executive Order 
12866;
    2. Is not a ``significant rule'' under the DOT Regulatory Policies 
and Procedures (44 FR 11034, February 26, 1979); and
    3. Will not have a significant economic impact, positive or 
negative, on a substantial number of small entities under the criteria 
of the Regulatory Flexibility Act.
    We prepared a regulatory evaluation of the estimated costs to 
comply with this proposed AD and placed it in the AD docket. See the 
ADDRESSES section for a location to examine the regulatory evaluation.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Safety.

The Proposed Amendment

    Accordingly, under the authority delegated to me by the 
Administrator, the FAA proposes to amend 14 CFR part 39 as follows:

PART 39--AIRWORTHINESS DIRECTIVES

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

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


Sec.  39.13  [Amended]

    2. The Federal Aviation Administration (FAA) amends Sec.  39.13 by 
removing amendment 39-8469 (58 FR 5576, January 22, 1993) and adding 
the following new airworthiness directive (AD):

McDonnell Douglas: Docket No. FAA-2008-0123; Directorate Identifier 
2007-NM-056-AD.

Comments Due Date

    (a) The FAA must receive comments on this AD action by March 21, 
2008.

Affected ADs

    (b) This AD supersedes AD 93-01-15.

Applicability

    (c) This AD applies to all McDonnell Douglas airplanes 
identified in Table 1 of this AD, certificated in any category.

                         Table 1.--Applicability
------------------------------------------------------------------------
                                  Model
-------------------------------------------------------------------------
(1) DC-8-11, DC-8-12, DC-8-21, DC-8-31, DC-8-32, DC-8-33, DC-8-41, DC-8-
 42, and DC-8-43 airplanes.
(2) DC-8-51, DC-8-52, DC-8-53, and DC-8-55 airplanes.
(3) DC-8F-54 and DC-8F-55 airplanes.
(4) DC-8-61, DC-8-62, and DC-8-63 airplanes.
(5) DC-8-61F, DC-8-62F, and DC-8-63F airplanes.
(6) DC-8-71, DC-8-72, and DC-8-73 airplanes.
(7) DC-8-71F, DC-8-72F, and DC-8-73F airplanes.
------------------------------------------------------------------------


[[Page 6626]]

Unsafe Condition

    (d) This AD results from a significant number of these airplanes 
approaching or exceeding the design service goal on which the 
initial type certification approval was predicated. We are issuing 
this AD to detect and correct fatigue cracking that could compromise 
the structural integrity of these airplanes.

Compliance

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

Certain Requirements of AD 93-01-15

Revise the FAA-Approved Maintenance Inspection Program

    (f) Within 6 months after February 26, 1993 (the effective date 
of AD 93-01-15), incorporate a revision of the FAA-approved 
maintenance inspection program that provides no less than the 
required inspection of the Principal Structural Elements (PSE's) 
defined in Sections 2 and 3 of Volume I of McDonnell Douglas Report 
No. L26-011, ``DC-8 Supplemental Inspection Document (SID),'' dated 
March 1991, in accordance with Section 2 of Volume III-91, dated 
April 1991, of that document. The non-destructive inspection 
techniques set forth in Sections 2 and 3 of Volume II, dated March 
1991, of that SID provide acceptable methods for accomplishing the 
inspections required by this AD. All inspection results, negative or 
positive, must be reported to McDonnell Douglas, in accordance with 
the instructions of Section 2 of Volume III-91 of the SID. 
Information collection requirements contained in this regulation 
have been approved by the OMB under the provisions of the Paperwork 
Reduction Act of 1980 (44 U.S.C. 3501 et seq.) and have been 
assigned OMB Control Number 2120-0056.

Corrective Action

    (g) Cracked structure detected during the inspections required 
by paragraph (f) of this AD must be repaired before further flight, 
in accordance with a method approved by the Manager, Los Angeles 
Aircraft Certification Office (ACO), FAA, Transport Airplane 
Directorate.

New Requirements of This AD

Revision of the Maintenance Inspection Program

    (h) Within 12 months after the effective date of this AD, 
incorporate a revision of the FAA-approved maintenance inspection 
program that provides for inspection(s) of the PSEs, in accordance 
with Boeing Report No. L26-011, ``DC-8 All Series Supplemental 
Inspection Document (SID),'' Volume I, Revision 6, dated July 2005. 
Incorporation of this revision ends the requirements of paragraphs 
(f) and (g) of this AD.

Non-Destructive Inspections (NDIs)

    (i) For all PSEs listed in Section 2 of Boeing Report No. L26-
011, ``DC-8 All Series Supplemental Inspection Document (SID),'' 
Volume I, Revision 6, dated July 2005, perform an NDI for fatigue 
cracking of each PSE, in accordance with the NDI procedures 
specified in Section 2 of McDonnell Douglas Report No. L26-011, 
``DC-8 Supplemental Inspection Document (SID),'' Volume II, Revision 
8, dated January 2005, at the times specified in paragraph (i)(1), 
(i)(2), or (i)(3) of this AD, as applicable.
    (1) For airplanes that have less than three quarters of the 
fatigue life threshold (\3/4\NTH) as of the effective 
date of this AD: Perform the NDI for fatigue cracking at the times 
specified in paragraphs (i)(1)(i) and (i)(1)(ii) of this AD. After 
reaching the threshold (NTH), repeat the inspection for 
that PSE at intervals not to exceed [Delta]NDI/2.
    (i) Perform an initial NDI no earlier than one-half of the 
threshold (\1/2\NTH) but before reaching three-quarters 
of the threshold (\3/4\NTH), or within 60 months after 
the effective date of this AD, whichever occurs later.
    (ii) Repeat the NDI no earlier than \3/4\NTH but 
before reaching the threshold (NTH), or within 18 months 
after the inspection required by paragraph (i)(1)(i) of this AD, 
whichever occurs later.

    Note 1: The DC-8 SID and this AD refer to the repetitive 
inspection interval as [Delta]NDI/2. However, the headings of the 
tables in Section 4 of Volume I of the DC-8 SID refer to the 
repetitive inspection interval of NDI/2. The values listed under 
NDI/2 in the tables in Section 4 of Volume I of the DC-8 SID are the 
repetitive inspection intervals, [Delta]NDI/2.

    (2) For airplanes that have reached or exceeded three-quarters 
of the fatigue life threshold (\3/4\NTH), but less than 
the threshold (NTH), as of the effective date of this AD: 
Perform an NDI before reaching the threshold (NTH), or 
within 18 months after the effective date of this AD, whichever 
occurs later. Thereafter, after passing the threshold 
(NTH), repeat the inspection for that PSE at intervals 
not to exceed [Delta]NDI/2.
    (3) For airplanes that have reached or exceeded the fatigue life 
threshold (NTH) as of the effective date of this AD: 
Perform an NDI within 18 months after the effective date of this AD. 
Thereafter, repeat the inspection for that PSE at intervals not to 
exceed [Delta]NDI/2.

Discrepant Findings

    (j) If any discrepancy (e.g., differences on the airplane from 
the NDI reference standard, such as PSEs that cannot be inspected as 
specified in McDonnell Douglas Report No. L26-011, ``DC-8 
Supplemental Inspection Document (SID),'' Volume II, Revision 8, 
dated January 2005, or do not match rework, repair, or modification 
descriptions in Boeing Report No. L26-011, ``DC-8 All Series 
Supplemental Inspection Document (SID),'' Volume I, Revision 6, 
dated July 2005) is detected during any inspection required by 
paragraph (i) of this AD, do the action specified in paragraph 
(j)(1) or (j)(2) of this AD, as applicable.
    (1) If a discrepancy is detected during any inspection done 
before 3/4NTH or NTH: The area of the PSE 
affected by the discrepancy must be inspected before NTH 
or within 18 months after the discovery of the discrepancy, 
whichever occurs later, in accordance with a method approved by the 
Manager, Los Angeles ACO.
    (2) If a discrepancy is detected during any inspection done 
after NTH: The area of the PSE affected by the 
discrepancy must be inspected before the accumulation of an 
additional [Delta]NDI/2 or within 18 months after the discovery of 
the discrepancy, whichever occurs later, in accordance with a method 
approved by the Manager, Los Angeles ACO.

Reporting Requirements

    (k) All negative or positive findings of the inspections done in 
accordance with paragraph (i) of this AD must be reported to Boeing 
at the times specified in, and in accordance with, the instructions 
contained in Section 4 of Boeing Report No. L26-011, ``DC-8 All 
Series Supplemental Inspection Document (SID),'' Volume I, Revision 
6, dated July 2005. Information collection requirements contained in 
this regulation have been approved by the Office of Management and 
Budget (OMB) under the provisions of the Paperwork Reduction Act of 
1980 (44 U.S.C. 3501 et seq.) and have been assigned OMB Control 
Number 2120-0056.

Corrective Actions

    (l) Any cracked structure of a PSE detected during any 
inspection required by paragraph (i) of this AD must be repaired 
before further flight using a method approved in accordance with the 
procedures specified in paragraph (o) of this AD. Accomplish the 
actions described in paragraphs (l)(1), (l)(2), and (l)(3) of this 
AD, at the times specified.
    (1) Within 18 months after repair, do a damage tolerance 
assessment (DTA) that defines the threshold for inspection of the 
repair and submit the assessment for approval.
    (2) Before reaching 75% of the repair threshold as determined in 
paragraph (l)(1) of this AD, submit the inspection methods and 
repetitive inspection intervals for the repair for approval.
    (3) Before the repair threshold, as determined in paragraph 
(l)(1) of this AD, incorporate the inspection method and repetitive 
inspection intervals into the FAA-approved structural maintenance or 
inspection program for the airplane.

    Note 2: For the purposes of this AD, we anticipate that 
submissions of the DTA of the repair, if acceptable, should be 
approved within 6 months after submission.


    Note 3: FAA Order 8110.54, ``Instructions for Continued 
Airworthiness,'' dated July 1, 2005, provides additional guidance 
about the approval of repairs to PSEs.

Inspection for Transferred Airplanes

    (m) Before any airplane that has exceeded the fatigue life 
threshold (NTH) 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 as specified in 
paragraph (m)(1) or (m)(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 date for

[[Page 6627]]

that PSE inspection. The compliance time for accomplishing this 
inspection must be measured from the last inspection done by the 
previous operator. After each inspection has been done once, each 
subsequent inspection must be done 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, Los Angeles ACO. After 
each inspection has been done once, each subsequent inspection must 
be done in accordance with the new operator's schedule.

Acceptable for Compliance

    (n) McDonnell Douglas Report No. MDC 91K0262, ``DC-8 Aging 
Aircraft Repair Assessment Program Document,'' Revision 1, dated 
October 2000, provides inspection/replacement programs for certain 
repairs to the fuselage pressure shell. Accomplishing these repairs 
and inspection/replacement programs before the effective date of 
this AD is considered acceptable for compliance with the 
requirements of paragraphs (g) and (l) of this AD for repairs 
subject to that document.

Alternative Methods of Compliance (AMOCs)

    (o)(1) The Manager, Los Angeles ACO, has the authority to 
approve AMOCs for this AD, if requested in accordance with the 
procedures found in 14 CFR 39.19.
    (2) To request a different method of compliance or a different 
compliance time for this AD, follow the procedures in 14 CFR 39.19. 
Before using any approved AMOC on any airplane to which the AMOC 
applies, notify your appropriate principal inspector (PI) in the FAA 
Flight Standards District Office (FSDO), or lacking a PI, your local 
FSDO.
    (3) An AMOC that provides an acceptable level of safety may be 
used for any repair required by this AD, if it is approved by an 
Authorized Representative for the Boeing Commercial Airplanes 
Delegation Option Authorization Organization who has been authorized 
by the Manager, Los Angeles ACO, to make those findings. For a 
repair method to be approved, the repair must meet the certification 
basis of the airplane and 14 CFR 25.571, Amendment 45, and the 
approval must specifically refer to this AD.
    (4) AMOCs approved previously in accordance with AD 93-01-15 are 
approved as AMOCs for the corresponding provisions of this AD.

    Issued in Renton, Washington, on January 24, 2008.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
 [FR Doc. E8-1989 Filed 2-4-08; 8:45 am]

BILLING CODE 4910-13-P
