[Federal Register Volume 66, Number 134 (Thursday, July 12, 2001)]
[Proposed Rules]
[Pages 36516-36520]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 01-17433]



[[Page 36516]]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 99-NM-105-AD]
RIN 2120-AA64


Airworthiness Directives; Boeing Model 727, 727C, 727-100, 727-
100C, 727-200, and 727-200F Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: This document proposes the supersedure of an existing 
airworthiness directive (AD), applicable to all Boeing Model 727, 727C, 
727-100, 727-100C, 727-200, and 727-200F series airplanes, that 
currently requires repetitive inspections to find cracking of the lower 
skin panel at the lower row of fasteners in certain lap joints of the 
fuselage, and repair, if necessary. This action would limit the 
applicability of the existing AD; add certain repetitive inspections; 
revise certain compliance times; and add certain modifications. This 
proposal is prompted by the FAA's determination that, in light of 
additional crack findings, certain modifications of the fuselage lap 
joints are necessary. The actions specified by the proposed AD are 
intended to find and fix fatigue cracking of the fuselage lap joints, 
which could result in sudden fracture and failure of the lower skin lap 
joints, and rapid decompression of the airplane.

DATES: Comments must be received by August 27, 2001.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 99-NM-105-AD, 1601 Lind Avenue, SW., 
Renton, Washington 98055-4056. Comments may be inspected at this 
location between 9:00 a.m. and 3:00 p.m., Monday through Friday, except 
Federal holidays. Comments may be submitted via fax to (425) 227-1232. 
Comments may also be sent via the Internet using the following address: 
[email protected]. Comments sent via fax or the Internet must 
contain ``Docket No. 99-NM-105-AD'' in the subject line and need not be 
submitted in triplicate. Comments sent via the Internet as attached 
electronic files must be formatted in Microsoft Word 97 for Windows or 
ASCII text.
    The service information referenced in the proposed rule may be 
obtained from Boeing Commercial Airplane Group, P.O. Box 3707, Seattle, 
Washington 98124-2207. This information may be examined at the FAA, 
Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, 
Washington.

FOR FURTHER INFORMATION CONTACT: Walt Sippel, Aerospace Engineer, 
Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office, 
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 
227-2774; fax (425) 227-1181.

SUPPLEMENTARY INFORMATION:

Comments Invited

    Interested persons are invited to participate in the making of the 
proposed rule by submitting such written data, views, or arguments as 
they may desire. Communications shall identify the Rules Docket number 
and be submitted in triplicate to the address specified above. All 
communications received on or before the closing date for comments, 
specified above, will be considered before taking action on the 
proposed rule. The proposals contained in this action may be changed in 
light of the comments received.
    Submit comments using the following format:
     Organize comments issue-by-issue. For example, discuss a 
request to change the compliance time and a request to change the 
service bulletin reference as two separate issues.
     For each issue, state what specific change to the proposed 
AD is being requested.
     Include justification (e.g., reasons or data) for each 
request.
    Comments are specifically invited on the overall regulatory, 
economic, environmental, and energy aspects of the proposed rule. All 
comments submitted will be available, both before and after the closing 
date for comments, in the Rules Docket for examination by interested 
persons. A report summarizing each FAA-public contact concerned with 
the substance of this proposal will be filed in the Rules Docket.
    Commenters wishing the FAA to acknowledge receipt of their comments 
submitted in response to this action must submit a self-addressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket Number 99-NM-105-AD.'' The postcard will be date stamped and 
returned to the commenter.

Availability of NPRMs

    Any person may obtain a copy of this NPRM by submitting a request 
to the FAA, Transport Airplane Directorate, ANM-114, Attention: Rules 
Docket No. 99-NM-105-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    On February 10, 1999, the FAA issued AD 99-04-22, amendment 39-
11047 (64 FR 7774, February 17, 1999), applicable to all Boeing Model 
727, 727-100, 727-200, 727C, 727-100C, and 727-200F series airplanes, 
to require repetitive inspections to find cracking of the lower skin 
panel at the lower row of fasteners in certain lap joints of the 
fuselage, and repair, if necessary. That AD also provides for optional 
terminating action for certain repetitive inspections. That action was 
prompted by a report of fatigue cracking in the lower skin panel at the 
lower row of fasteners of the fuselage lap joints. The requirements of 
that AD are intended to find and fix such fatigue cracking, which could 
result in sudden fracture and failure of the lower skin lap joints, and 
rapid decompression of the airplane.

Actions Since Issuance of Previous Rule

    Since the issuance of AD 99-04-22, the FAA has received additional 
reports of fatigue cracking in the lower skin of the lap joints of the 
fuselage on Model 727 series airplanes that had accumulated as few as 
36,781 total flight cycles, and several airplanes that had accumulated 
more than 50,000 flight cycles. The airplanes having more than 50,000 
flight cycles were previously inspected per that AD. Further 
investigation revealed additional cracking and corrosion in various 
areas of the crown skin lap joints at the fastener locations. The 
majority of the cracks occurred at left and right stringers 4 and 26. 
The FAA finds that this damage can occur at those stringer locations 
between 30,000 and 50,000 flight cycles. These cracks are not always 
detectable using the external inspection procedures required by AD 99-
04-22, and can link up with adjacent cracks causing multiple site 
damage, which can result in a rapid decompression of the fuselage.
    Based on these findings, the FAA has determined that the current 
repetitive external detailed visual inspection procedures required by 
AD 99-04-22 are not adequate for finding cracks in these locations. 
Therefore, the FAA finds that additional rulemaking is necessary to 
require accomplishment of certain lap joint modifications and pre-and 
post-mod inspections, instead of the repetitive external detailed 
visual inspections.

[[Page 36517]]

Supplemental Type Certificate (STC) Holders

    The FAA has determined that approximately half of the airplanes 
specified in the applicability of this proposed rule have been modified 
from a passenger configuration to an all-cargo configuration. The FAA 
has approved several service bulletins (listed below) that could be 
approved as alternative methods of compliance for the proposed 
modification requirements, but based on the number of affected 
airplanes, will instead be included in the proposed rule. The holders 
of STCs for these modified airplanes have developed these service 
bulletins to address modification/repair of the longitudinal lap joints 
in the area of the cargo door doubler only, but all other applicable 
areas also must be inspected and modified per Boeing Service Bulletin 
727-53A0222, Revision 1, dated March 15, 2001.

Public Meeting

    A joint FAA and Boeing meeting was held on July 25-27, 2000, to 
inform industry of the activity on Boeing Model 727 and 737 fuselage 
lap joints. Others in attendance were representatives from STC holders, 
air carriers, and repair stations, as well as Principal Maintenance 
Inspectors (PMI) from the FAA's Flight Standards Service. The objective 
of the meeting was to provide an overview of the FAA rulemaking 
process; discuss the recommendations of Boeing Service Bulletins 727-
53A0222 and 737-53A1177, including background information; standardize 
the 727 and 737 service bulletins, where possible; and discuss the 
impact that the recommended service bulletin modifications would have 
on industry.
    During the meetings, holders of certain STCs presented information 
pertaining to service bulletin activity for those airplanes that have 
been modified from a passenger to an all-cargo configuration. The 
meeting accomplished the objective of exchanging information between 
the FAA, Boeing, and industry on various aspects of Boeing Models 727 
and 737 fuselage lap joints, including compliance planning. As a result 
of the meeting, attendees recognized the importance of modifying 
certain lap joints before reaching the point of widespread fatigue 
damage. Suggestions to improve the service bulletins and clarify AD 
compliance issues were made by operators and PMIs, and have been 
incorporated into the service bulletins and the proposed ADs discussed 
below. The minutes of the meeting have been placed in the public 
docket.

Explanation of Relevant Service Information

    In addition to Boeing Service Bulletin 727-53A0222, Revision 1, the 
FAA has approved four service bulletins for STCs that modify affected 
airplanes from a passenger to an all-cargo configuration. These service 
bulletins address the areas of the lap joints that are physically 
externally covered by the addition of large doublers in the area of the 
cargo door. These doublers affect the loads in the lap joints, and for 
this reason the STC service bulletins provide inspections and 
modification instructions for those lap joint areas covered by the 
doublers.
    The FAA has reviewed and approved the following service bulletins:

------------------------------------------------------------------------
             Service Bulletin                           Date
------------------------------------------------------------------------
Boeing Service Bulletin 727-53A0222,        March 15, 2001.
 Revision 1, including Appendix A.
Aeronautical Engineers Inc., Service        May 7, 2001.
 Bulletin AEI 00-01, Revision A.
PEMCO World Air Services Bulletin 727-53-   June 6, 2001.
 0007, Revision 1.
Aircraft Technical Service, Inc., Service   May 7, 2001.
 Bulletin ATS 727-001.
Federal Express Corporation Service         May 16, 2001.
 Bulletin 00-029, Revision A.
------------------------------------------------------------------------

    The Boeing Service Bulletin describes, but is not limited to, the 
following procedures:
     Either a Low Frequency Eddy Current (LFEC) or internal 
detailed visual and Medium Frequency Eddy Current (MFEC) inspection for 
cracking of the lower row of fasteners in the lower skin of fuselage 
sections 41, 43, and 46 of the lap joints.
     A High Frequency Eddy Current (HFEC) inspection of the 
fastener holes to verify crack indications if cracks are found during 
the LFEC inspection; or accessing the inboard side of the skin to do an 
MFEC inspection of the lower row of fasteners for verification of 
cracking in the lower skin.
     After crack indications are verified: An internal detailed 
visual inspection and an MFEC inspection for damage of the entire skin 
panel of the lap joint.
     Repair of the damage per the structural repair manual if 
the damage is within one bay. And
     Modification of the fuselage lap joints, and a post-
modification inspection for cracking in the skin. The modification 
consists of cutting out the lap joint for the entire skin panel and 
installing an external doubler and tripler at stringers S-4L, S-4R, and 
S-26L.
    The STC service bulletins listed above describe procedures for a 
one-time pre-modification inspection for cracking of the lower row of 
fasteners in the lower skin of the lap joint, modification of the 
surrounding structure of the main cargo door and doublers, and 
repetitive post-modification HFEC inspections for cracking in the cargo 
door area. This is to be done concurrent with the modification of the 
fuselage lap joints specified in the Boeing service bulletin described 
above.
    Accomplishment of the actions specified in the service bulletins is 
intended to adequately address the identified unsafe condition.

Explanation of Requirements of Proposed Rule

    Since an unsafe condition has been identified that is likely to 
exist or develop on other products of this same type design, the 
proposed AD would supersede AD 99-04-22 to continue to require certain 
repetitive inspections to find cracking of the lower skin panel at the 
lower row of fasteners in certain lap joints of the fuselage, and 
repair, if necessary. The proposed AD also would limit the 
applicability; add certain repetitive inspections; revise certain 
compliance times; and add certain modifications. The actions would be 
required to be accomplished per the service bulletins described 
previously, except as discussed below.

Differences Between the Boeing Service Bulletin and This Proposed 
AD

    The FAA recognizes that the lap joint modification specified in 
this proposed AD would require jacking, shoring, removing interior 
components, and modifying certain lap joints, which would require 
taking the airplane out of service for as much as 22 days. This lengthy 
shop visit, as well as the relatively short compliance time required to 
accomplish this proposed AD, make it necessary for operators to engage 
in compliance planning to ensure that, when the deadline for compliance 
arrives, all of the required actions have been completed on all 
affected airplanes. Therefore, paragraph (c) of this proposed AD would 
require that operators submit to the FAA a compliance plan within 3 
months after the effective date of this AD. This will enable the FAA to 
verify that all operators will be able to meet the deadlines imposed by 
this proposed AD.
    While the service bulletin specifies that the manufacturer may be 
contacted for disposition of certain repair conditions, this proposal 
would require

[[Page 36518]]

that the repair of those conditions be accomplished per a method 
approved by the FAA, or per data meeting the type certification basis 
of the airplane approved by a Boeing Company Designated Engineering 
Representative who has been authorized by the Manager, Seattle Aircraft 
Certification Office, to make such findings.

Cost Impact

    There are approximately 900 Model 727 series airplanes of the 
affected design in the worldwide fleet. The FAA estimates that 700 
airplanes of U.S. registry would be affected by this proposed AD.
    The inspections that are currently required by AD 99-04-22 take 
approximately 8 work hours per airplane to accomplish, at an average 
labor rate of $60 per work hour. Based on these figures, the cost 
impact of the currently required actions on U.S. operators is estimated 
to be $480 per airplane.
    The FAA estimates that the inspections proposed by this NPRM will 
impose the following costs, given an average labor rate of $60 per work 
hour:

------------------------------------------------------------------------
                                                              Costs per
    Service information & inspection method      Work hours   inspection
                                                                cycle
------------------------------------------------------------------------
Boeing SB 727-53A0222--External LFEC..........           16         $960
Boeing SB 727-53A0222--Internal Detailed                120        7,200
 Visual and MFEC (Passenger Airplanes)........
Boeing SB 727-53A0222--Internal Detailed                 40        2,400
 Visual and MFEC (Cargo Airplanes)............
AEI SB 00-01..................................           12          720
PEMCO SB 727-53-0007..........................           12          720
ATS SB 727-001................................           12          720
Federal Express SB 00-029.....................           12          720
------------------------------------------------------------------------

    The FAA estimates that, during the 10-year period after issuance of 
the proposed AD, worldwide operators will be required to modify 360 
Model 727 series airplanes. The modification required by the proposed 
AD would take approximately 1,200 work hours to accomplish, at an 
average labor rate of $60 per work hour. The worldwide cost impact of 
the required modification is estimated to be $37,413,000 over 10 years, 
or an average of $3,741,000 per year. The highest impact year is the 
first year after issuance of the AD; an estimated 56 Model 727 series 
airplanes would require modification in that year. The affected Model 
727 airplanes operated by U.S. operators comprise approximately 78 
percent of the total worldwide costs. Therefore, the highest cost 
impact of the modification in any given year is estimated to be 
$4,527,000 for U.S. operators.
    The compliance plan that is proposed in this AD action would take 
approximately 24 work hours per airplane to accomplish, at an average 
labor rate of $60 per work hour. Based on these figures, the cost 
impact of the compliance plan on U.S. operators is estimated to be 
$1,008,000, or $1,440 per airplane.
    The cost impact figures discussed above are based on assumptions 
that no operator has yet accomplished any of the current or proposed 
requirements of this AD action, and that no operator would accomplish 
those actions in the future if this AD were not adopted. The cost 
impact figures discussed in AD rulemaking actions represent only the 
time necessary to perform the specific actions actually required by the 
AD. These figures typically do not include incidental costs, such as 
the time required to gain access and close up, planning time, or time 
necessitated by other administrative actions.

Regulatory Impact

    The regulations proposed herein 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. Therefore, it 
is determined that this proposal would not have federalism implications 
under Executive Order 13132.
    For the reasons discussed above, I certify that this 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) if promulgated, will not have a significant economic impact, 
positive or negative, on a substantial number of small entities under 
the criteria of the Regulatory Flexibility Act. A copy of the draft 
regulatory evaluation prepared for this action is contained in the 
Rules Docket. A copy of it may be obtained by contacting the Rules 
Docket at the location provided under the caption ADDRESSES.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Safety.

The Proposed Amendment

    Accordingly, pursuant to the authority delegated to me by the 
Administrator, the Federal Aviation Administration proposes to amend 
part 39 of the Federal Aviation Regulations (14 CFR part 39) as 
follows:

PART 39--AIRWORTHINESS DIRECTIVES

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

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


Sec. 39.13  [Amended]

    2. Section 39.13 is amended by removing amendment 39-11047 (64 FR 
7774, February 17, 1999), and by adding a new airworthiness directive 
(AD), to read as follows:

Boeing: Docket 99-NM-105-AD. Supersedes AD 99-04-22, amendment 39-
11047.

    Applicability: Model 727 series airplanes, as listed in Boeing 
Service Bulletin 727-53A0222, Revision 1, including Appendix A, 
dated March 15, 2001, certificated in any category.

    Note 1: This AD applies to each airplane identified in the 
preceding applicability provision, regardless of whether it has been 
modified, altered, or repaired in the area subject to the 
requirements of this AD. For airplanes that have been modified, 
altered, or repaired so that the performance of the requirements of 
this AD is affected, the owner/operator must request approval for an 
alternative method of compliance per paragraph (l)(1) of this AD. 
The request should include an assessment of the effect of the 
modification, alteration, or repair on the unsafe condition 
addressed by this AD; and, if the unsafe condition has not been 
eliminated, the request should include specific proposed actions to 
address it.

    Compliance: Required as indicated, unless accomplished 
previously.
    To find and fix fatigue cracking in the lower skin panel at the 
lower row of fasteners of the fuselage lap joints, which could 
result in sudden fracture and failure of the lap joints, and rapid 
decompression of the airplane; accomplish the following:

[[Page 36519]]

Repetitive Inspections

    (a) Do either an external low frequency eddy current (LFEC) 
inspection to find cracking, or both internal detailed visual and 
medium frequency eddy current (MFEC) inspections to find cracking or 
corrosion in the lower skin panels of the lower row of fasteners of 
the fuselage lap joints at the earlier of the times specified in 
paragraphs (a)(1) and (a)(2) of this AD on lap joints identified in 
Tables A through H and J through N; per Paragraph 1., Planning 
Information, of Boeing Service Bulletin 727-53A0222, Revision 1, 
including Appendix A, dated March 15, 2001. Except as provided by 
paragraph (b) of this AD, after doing the applicable initial 
inspection, repeat that inspection at the intervals specified in 
Tables A through G or J through N of the service bulletin, as 
applicable.
    (1) At the latest of the times specified for the initial 
inspection in Tables A through H (for Groups 1, 2, 3, and 5 
airplanes), or Tables J through N (for Groups 3 and 4 airplanes), as 
applicable, of Section 1.E. ``Compliance,'' of the service bulletin, 
except where the compliance time in the service bulletin specifies a 
compliance time interval based on ``the release of this service 
bulletin,'' this AD requires compliance within the interval 
specified in the service bulletin ``after the effective date of this 
AD.''
    (2) Within 600 flight cycles after the last LFEC inspection or 
7,000 flight cycles after the last HFEC inspection, if any, is 
accomplished in accordance with AD 99-04-22, amendment 39-11047.

    Note 2: Groups 1-5 are defined in the effectivity section of the 
service bulletin.

    (b) The repetitive inspection intervals for lap joints 
identified in Table H of Paragraph 1., Planning Information, of 
Boeing Service Bulletin 727-53A0222, Revision 1, including Appendix 
A, dated March 15, 2001, decrease with increasing flight cycles. 
Perform the repetitive inspections listed in Table H of the service 
bulletin at the following thresholds and intervals:
    (1) If, at the time of the most recent inspection required by 
paragraph (a) or (b) of this AD, the airplane has accumulated fewer 
than 35,000 total flight cycles: Perform LFEC inspections at 
intervals not to exceed 600 flight cycles, or detailed internal 
visual and MFEC inspections at intervals not to exceed 7,000 flight 
cycles.
    (2) If, at the time of the most recent inspection required by 
paragraph (a) or (b) of this AD, the airplane has accumulated 35,000 
or more, but fewer than 45,000 flight cycles: Perform LFEC 
inspections at intervals not to exceed 600 flight cycles, or 
detailed internal visual and MFEC inspections at intervals not to 
exceed 7,000 flight cycles.
    (3) If, at the time of the most recent inspection required by 
paragraph (a) or (b) of this AD, the airplane has accumulated 45,000 
or more, but fewer than 54,999 flight cycles: Perform detailed 
internal visual and MFEC inspections at intervals not to exceed 
2,000 flight cycles.
    (4) If, at the time of the most recent inspection required by 
paragraph (a) or (b) of this AD, the airplane accumulated 55,000 or 
more total flight cycles: Perform LFEC inspections at intervals not 
to exceed 300 flight cycle intervals.

    Note 3: For the purposes of this AD, a detailed visual 
inspection is defined as: ``An intensive visual examination of a 
specific structural area, system, installation, or assembly to find 
damage, failure, or irregularity. Available lighting is normally 
supplemented with a direct source of good lighting at intensity 
deemed appropriate by the inspector. Inspection aids such as mirror, 
magnifying lenses, etc., may be used. Surface cleaning and elaborate 
access procedures may be required.''

Compliance Plan

    (c) Within 3 months after the effective date of this AD, submit 
a plan to the FAA identifying a schedule for compliance with 
paragraph (d) of this AD. This schedule must include, for each of 
the operator's affected airplanes, the dates and maintenance events 
(e.g., letter checks) when the required actions will be 
accomplished. For the purposes of this paragraph, ``FAA'' means the 
Principal Maintenance Inspector (PMI) for operators that are 
assigned a PMI, or the cognizant Flight Standards District Office 
for other operators. 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.

    Note 4: Operators are not required to submit revisions to the 
compliance plan required by paragraph (c) of this AD to the FAA.

Modification/Inspections

    (d) For Model 727-200 series airplanes: Accomplish the 
modification listed in Table H of Paragraph 1., Planning 
Information, of Boeing Service Bulletin 727-53A0222, Revision 1, 
including Appendix A, dated March 15, 2001, at the threshold in 
paragraph (d)(1), (d)(2), or (d)(3) of this AD, as applicable. 
Within 35,000 flight cycles after doing the modification, do the 
post-modification inspection for cracking in the skin, per Part III 
of the Accomplishment Instructions of the service bulletin:
    (1) For airplanes that have accumulated less than 35,000 total 
flight cycles on the effective date of the AD: Accomplish the 
modification prior to 48,000 total flight cycles.
    (2) For airplanes that have accumulated between 35,000 and 
54,999 total flight cycles on the effective date of the AD: 
Accomplish the modification prior to 55,000 total flight cycles, or 
within 2,000 total flight cycles of the effective date of this AD.
    (3) For airplanes that have accumulated 55,000 or greater total 
flight cycles on the effective date of the AD: Accomplish the 
modification within 2,000 flight cycles after the effective date of 
this AD.

Repair

    (e) If any cracking or corrosion is found during any inspection 
required by paragraph (a), (b), or (d) of this AD: Before further 
flight, repair per Boeing Service Bulletin 727-53A0222, Revision 1, 
including Appendix A, dated March 15, 2001. Where the service 
bulletin specifies to contact Boeing for repair instructions, repair 
per a method approved by the Manager, Seattle ACO; or per data 
meeting the type certification basis of the airplane approved by a 
Boeing Company DER who has been authorized by the Manager, Seattle 
ACO, to make such findings. For a repair method to be approved by 
the Manager, Seattle ACO, as required by this paragraph, the 
approval letter must specifically reference this AD.

Concurrent Modifications

    (f) For Model 727-200 series airplanes modified per supplemental 
type certificate (STC) SA1368SO or SA1797SO: Concurrent with the 
modification of the fuselage lap joints required by paragraph (d) of 
this AD, do the inspection for cracking of the lower row of 
fasteners in the lower skin of the lap joints, and the modification 
specified in Aeronautical Engineers Inc., Service Bulletin AEI 00-
01, Revision A, dated May 7, 2001, per the service bulletin.
    (g) For Model 727-200 series airplanes modified per STC SA1444SO 
and SA1509SO: Concurrent with the modification of the fuselage lap 
joints required by paragraph (d) of this AD, do the inspection for 
cracking of the lower row of fasteners in the lower skin of the lap 
joints, and the modification specified in PEMCO World Air Services 
Bulletin 727-53-0007, Revision 1, dated June 6, 2001, per the 
service bulletin.
    (h) For Model 727-200 series airplanes modified per STC 
SA00015AT: Concurrent with the modification of the fuselage lap 
joints required by paragraph (d) of this AD, do the inspection for 
cracking of the lower row of fasteners in the lower skin of the lap 
joints, and the modification specified in Aircraft Technical 
Service, Inc., Service Bulletin ATS 727-001, dated May 7, 2001, per 
the service bulletin.
    (i) For Model 727-200 series airplanes modified per STC SA176SO: 
Concurrent with the modification of the fuselage lap joints required 
by paragraph (d) of this AD, do the inspection for cracking of the 
lower row of fasteners in the lower skin of the lap joints, and the 
modification specified in Federal Express Corporation Service 
Bulletin 00-029, Revision A, dated May 16, 2001, per the service 
bulletin.
    (j) Within 2,200 flight cycles after doing the applicable 
modification specified in paragraph (f), (g), (h), or (i) of this 
AD, do the post-modification inspection for cracking in the skin per 
the applicable service bulletin specified in Table 1, below. Repeat 
the applicable inspection after that at intervals not to exceed 
2,200 flight cycles. Table 1 follows:

                                 Table 1
------------------------------------------------------------------------
             Service Bulletin                           Date
------------------------------------------------------------------------
(1) Aeronautical Engineers Inc., Service    May 7, 2001.
 Bulletin AEI 00-01, Revision A.
(2) PEMCO World Air Services Bulletin 727-  June 6, 2001.
 53-0007, Revision 1.

[[Page 36520]]

 
(3) Aircraft Technical Service, Inc.,       May 7, 2001.
 Service Bulletin ATS 727-001.
(4) Federal Express Corporation Service     May 16, 2001.
 Bulletin 00-029, Revision A.
------------------------------------------------------------------------

Repair

    (k) If any cracking is found during any inspection required by 
paragraph (f), (g), (h), or (i) of this AD: Before further flight, 
repair per the applicable service bulletin as provided in Table 1 in 
paragraph (j) of this AD. Where cracks exceed the limits provided in 
the service bulletin, and the bulletin specifies to contact the 
provider of the service bulletin for repair instructions, prior to 
further flight, repair per a method approved by the Manager, Seattle 
ACO. If any cracking is found is during any inspection required by 
paragraph (j) of this AD: Before further flight, repair per a method 
approved by the Manager, Seattle ACO. For a repair method to be 
approved by the Manager, Seattle ACO, as required by this paragraph, 
the approval letter must specifically reference this AD.

Alternative Methods of Compliance

    (l)(1) An alternative method of compliance or adjustment of the 
compliance time that provides an acceptable level of safety may be 
used if approved by the Manager, Seattle ACO. Operators shall submit 
their requests through an appropriate FAA PMI, who may add comments 
and then send it to the Manager, Seattle ACO.
    (2) Alternative methods of compliance, approved previously per 
AD 99-04-22, amendment 39-11047, are approved as alternative methods 
of compliance with this AD.

    Note 5: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Seattle ACO.

Special Flight Permits

    (m) Special flight permits may be issued per sections 21.197 and 
21.199 of the Federal Aviation Regulations (14 CFR 21.197 and 
21.199) to operate the airplane to a location where the requirements 
of this AD can be accomplished.

    Issued in Renton, Washington, on July 6, 2001.
Vi L. Lipski,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 01-17433 Filed 7-11-01; 8:45 am]
BILLING CODE 4910-13-P