[Federal Register: December 8, 2003 (Volume 68, Number 235)]
[Proposed Rules]               
[Page 68308-68310]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr08de03-12]                         

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2002-NM-275-AD]
RIN 2120-AA64

 
Airworthiness Directives; Boeing Model 767 Series Airplanes 
Powered by General Electric or Pratt & Whitney Engines

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 certain Boeing Model 767 
series airplanes powered by General Electric or Pratt & Whitney 
engines, that currently requires repetitive inspections to detect 
discrepancies of the four aft-most fastener holes in the horizontal 
tangs of the midspar fitting of the strut, and corrective actions, if 
necessary. That AD also provides an optional terminating action for 
repetitive inspections. This proposal would expand the area on which 
the inspections are required. This proposal is prompted by reports of 
cracking at the third row of fasteners in the midspar fitting. The 
actions specified by the proposed AD are intended to prevent fatigue 
cracking in the primary strut structure and reduced structural 
integrity of the strut, which could result in separation of the strut 
and engine. This action is intended to address the identified unsafe 
condition.

DATES: Comments must be received by January 22, 2004.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 2002-NM-275-AD, 1601 Lind Avenue, SW., 
Renton, Washington 98055-4056. Comments may be inspected at this 
location between 9 a.m. and 3 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: 9-anm-nprmcomment@faa.gov. Comments sent via fax or the Internet must 
contain ``Docket No. 2002-NM-275-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 or 2000 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: Suzanne Masterson, Aerospace Engineer, 
Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office, 
1601 Lind Avenue, SW., Renton, Washington; telephone (425) 917-6441; 
fax (425) 917-6590.

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:
    [sbull] 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.
    [sbull] For each issue, state what specific change to the proposed 
AD is being requested.
    [sbull] 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 2002-NM-275-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. 2002-NM-275-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    On April 2, 2001, the FAA issued AD 2001-07-05, amendment 39-12170 
(66 FR 18523, April 10, 2001), applicable to certain Boeing Model 767 
series airplanes powered by General Electric or Pratt & Whitney 
engines, to require repetitive inspections to detect discrepancies of 
the aft-most fastener holes in the horizontal tangs of the midspar 
fitting of the strut, and corrective actions, if necessary. That AD was 
also prompted by a report indicating fatigue cracking of an inboard 
midspar fitting on the number two pylon. The requirements of that AD 
are intended to prevent fatigue cracking in primary strut structure and 
reduced structural integrity of the strut, which could result in 
separation of the strut and engine.

Actions Since Issuance of Previous Rule

    Since the issuance of AD 2001-07-05, the FAA has received reports 
of cracking at the third row of fasteners in the midspar fitting. AD 
2001-07-05 requires inspections of only the aft-most two rows 
consisting of four fastener holes in the horizontal tangs of the 
midspar fitting. The proposed AD expands the area for the inspections 
from four aft-most fastener holes in the midspar fitting to eight aft-
most fastener holes in the midspar fitting.

Issuance of New Service Information

    The FAA has reviewed and approved Boeing Service Bulletin 767-
54A0101,

[[Page 68309]]

Revision 3, dated September 5, 2002, which describes repetitive 
inspections of eight aft-most fastener holes in the midspar fitting, 
rather than only four aft-most fastener holes. Except as discussed 
below, the inspections described in this service bulletin are 
essentially identical to those specified in Revision 1 of the service 
bulletin, which was referenced in AD 2001-07-05 as the appropriate 
source of service information. Accomplishment of the actions specified 
in Revision 3 of the service bulletin is intended to adequately address 
the identified unsafe condition, except as described below.

Difference Between Proposed Rule and Service Bulletin

    Operators should note that, unlike the procedures described in 
Boeing Service Bulletin 767-54A0101, Revision 3, dated September 5, 
2002, during the first detailed inspection, this proposed AD allows for 
inspection of only four of the aft-most fastener holes as an option to 
inspecting all eight aft-most fastener holes. After the first detailed 
inspection, repetitive inspections would include all eight aft-most 
fastener holes as specified in the service bulletin.

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 2001-07-05 to require repetitive 
inspections to detect discrepancies of the eight aft-most fastener 
holes in the horizontal tangs of the midspar fitting of the strut, and 
corrective actions, if necessary.

Editorial Changes to the Existing Requirements

    The FAA has changed all references to a ``detailed visual 
inspection'' in paragraph (a)(1) of AD 2001-07-05 to ``detailed 
inspection.''
    The FAA has also added the words ``before further flight,'' to 
paragraphs (a)(2)(i) and (a)(2)(ii) of the proposed AD, which were 
inadvertently omitted from paragraphs (a)(2)(i) and (a)(2)(ii) of AD 
2001-07-05. It was our intent to follow the compliance times identified 
in the referenced service bulletin. We have included the compliance 
time for clarification.

Cost Impact

    There are approximately 625 airplanes of the affected design in the 
worldwide fleet. The FAA estimates that 263 airplanes of U.S. registry 
would be affected by this proposed AD.
    The detailed inspection that is proposed in this AD action would 
take approximately 1 work hour per airplane to accomplish, at an 
average labor rate of $65 per work hour. Based on these figures, the 
cost impact of the proposed inspection on U.S. operators is estimated 
to be $17,095, or $65 per airplane, per inspection cycle.
    The eddy current inspection that is proposed by the AD action would 
take approximately 3 work hours per airplane to accomplish, at an 
average labor rate of $65 per work hour. Based on these figures, the 
cost impact of the proposed inspection on U.S. operators is estimated 
to be $51,285, or $195 per airplane, per inspection cycle.
    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 39-12170 (66 FR 
18523, April 10, 2001), and by adding a new airworthiness directive 
(AD), to read as follows:

Boeing: Docket 2002-NM-275-AD. Supersedes AD 2001-07-05, amendment 
39-12170.

    Applicability: Model 767 series airplanes, as listed in Boeing 
Service Bulletin 767-54A0101, Revision 3, dated September 5, 2002; 
certificated in any category.
    Compliance: Required as indicated, unless accomplished 
previously.
    To prevent fatigue cracking in the primary strut structure and 
reduced structural integrity of the strut, which could result in 
separation of the strut and engine, accomplish the following:

Requirements of AD 2001-07-05

Repetitive Inspections

    (a) Except as provided by paragraph (b) of this AD, before the 
accumulation of 10,000 total flight cycles, or within 600 flight 
cycles after May 15, 2001 (the effective date of AD 2001-07-05, 
amendment 39-12170 (66 FR 18523, April 10, 2001), whichever occurs 
later: Accomplish the inspections required by paragraph (a)(1) or 
(a)(2) of this AD, as applicable.
    (1) Perform a detailed inspection of the four aft-most fastener 
holes in the horizontal tangs of the midspar fitting of the strut to 
detect cracking, in accordance with Part 1, ``Detailed Inspection,'' 
of the Accomplishment Instructions of Boeing Service Bulletin 767-
54A0101, Revision 1, dated February 3, 2000. If no cracking is 
detected, repeat the inspection thereafter at the applicable 
intervals specified in Table 1, ``Reinspection Intervals for Part 
1--Detailed Inspection'' included in Figure 1 of the service 
bulletin.

    Note 1: For the purposes of this AD, a detailed inspection is 
defined as: ``An intensive visual examination of a specific 
structural area, system, installation, or assembly to detect damage, 
failure, or irregularity. Available lighting is normally 
supplemented with a direct source of good lighting at intensity 
deemed appropriate by the inspector. Inspection aids such as mirror, 
magnifying lenses, etc., may be used. Surface cleaning and elaborate 
access procedures may be required.''


[[Page 68310]]


    (2) Perform a high frequency eddy current inspection of the four 
aft-most fastener holes in the horizontal tangs of the midspar 
fitting of the strut to detect discrepancies (cracking, incorrect 
fastener hole diameter), in accordance with Part 2, ``High Frequency 
Eddy Current (HFEC) Inspection,'' of the Accomplishment Instructions 
of the service bulletin. Accomplish the requirements specified in 
paragraph (a)(2)(i) or (a)(2)(ii) of this AD, as applicable; and 
repeat the inspection thereafter at the applicable intervals 
specified in Table 2, ``Reinspection Intervals for Part 2--HFEC 
Inspection'' included in Figure 1 of the service bulletin.
    (i) If no cracking is detected and the fastener hole diameter is 
less than or equal to 0.5322 inch, before further flight, rework the 
hole in accordance with Part 3 of the Accomplishment Instructions of 
the service bulletin.
    (ii) If no cracking is detected and the fastener hole diameter 
is greater than 0.5322 inch, before further flight, accomplish the 
requirements specified in either paragraph (c)(1) or (c)(2) of this 
AD.
    (b) For airplanes on which the two aft-most fasteners have been 
inspected in accordance with Boeing Service Bulletin 767-54A0101, 
Revision 1, dated February 3, 2000, prior to May 15, 2001: Perform 
the initial inspection of the four aft-most fasteners in accordance 
with paragraph (a) of this AD before the accumulation of 10,000 
total flight cycles, or within 1,500 flight cycles after May 15, 
2001, whichever occurs later.

Corrective Actions

    (c) If any cracking is detected after accomplishment of any 
inspection required by paragraph (a) of this AD, before further 
flight, accomplish the requirements specified in either paragraph 
(c)(1) or (c)(2) of this AD.
    (1) Accomplish the terminating action specified in Part 4 of the 
Accomplishment Instructions of Boeing Service Bulletin 767-54A0101, 
Revision 1, dated February 3, 2000; or Boeing Service Bulletin 767-
54A0101, Revision 3, dated September 5, 2002. Accomplishment of this 
paragraph terminates the requirements of this AD.
    (2) Replace the midspar fitting of the strut with a serviceable 
part, or repair in accordance with a method approved by the Manager, 
Seattle Aircraft Certification Office (ACO), FAA. Repeat the 
applicable inspection thereafter at the applicable time specified in 
paragraph (a)(1) or (a)(2) of this AD.
    (d) If any discrepancies (cracking, incorrect fastener hole 
diameter) are detected during any inspection required by paragraph 
(a) of this AD, for which the service bulletin specifies that the 
manufacturer may be contacted for disposition of those repair 
conditions: Before further flight, accomplish the corrective actions 
(including fastener hole rework and/or midspar fitting replacement) 
in accordance with a method approved by the Manager, Seattle ACO; or 
in accordance with data meeting the type certification basis of the 
airplane approved by a Boeing Company Designated Engineering 
Representative who has been authorized by the Manager, Seattle ACO, 
to make such findings. For a method to be approved by the Manager, 
Seattle ACO, as required by this paragraph, the Manager's approval 
letter must specifically reference this AD.

New Requirements of This AD

Additional Inspections

    (e) Within 10,000 total flight cycles, or within 600 flight 
cycles after the effective date of this AD, whichever occurs later: 
Perform the inspections specified in paragraph (a)(1) or (a)(2) of 
this AD, as applicable, on all eight aft-most fastener holes or the 
four forward fastener holes in the group of eight aft-most fastener 
holes not inspected per paragraph (a)(1), (a)(2), or (b) of this AD. 
The inspection must be done per the Accomplishment Instructions in 
Boeing Service Bulletin 767-54A0101, Revision 3, dated September 5, 
2002. Accomplishment of the applicable inspection on all eight aft-
most fastener holes constitutes terminating action for the 
repetitive inspection requirements of paragraphs (a)(1), (a)(2), and 
(b) of this AD.
    (f) If no cracking or discrepancy is detected during any 
inspection required by paragraph (e) of this AD: Perform the follow-
on actions specified in paragraph (a)(2)(i) or (a)(2)(ii) of this 
AD, as applicable, per the Accomplishment Instructions in Boeing 
Service Bulletin 767-54A0101, Revision 3, dated September 5, 2002; 
and repeat the inspections of all eight aft-most fastener holes 
thereafter at the applicable intervals specified in Table 1 of this 
AD.

    Table 1.--Repetitive Inspection Intervals for All Eight Aft-Most
                             Fastener Holes
------------------------------------------------------------------------
                 If--                        Repetitive intervals--
------------------------------------------------------------------------
(1) All eight aft-most fastener holes   At the applicable intervals
 were inspected per paragraph (e) of     specified in Table 1,
 this AD:                                ``Reinspection Intervals for
                                         Part 1--Detailed Inspection,''
                                         or Table 2, ``Reinspection
                                         Intervals for Part 2--HFEC
                                         Inspection,'' as applicable.
                                         Both tables are included in
                                         Figure 1 of the service
                                         bulletin.
(2) Only the four forward fastener      At the next scheduled repetitive
 holes in the group of eight aft-most    inspection required by
 fastener holes were inspected per       paragraph (a)(1) or (a)(2) of
 paragraph (e) of this AD:               this AD, as applicable.
                                         Thereafter at the applicable
                                         intervals specified in Table 1,
                                         ``Reinspection Intervals for
                                         Part 1--Detailed Inspection,''
                                         or Table 2, ``Reinspection
                                         Intervals for Part 2--HFEC
                                         Inspection,'' as applicable.
                                         Both tables are included in
                                         Figure 1 of the service
                                         bulletin.
------------------------------------------------------------------------

Corrective Actions

    (g) If any cracking or discrepancy is detected during any 
inspection required by paragraph (e) of this AD, before further 
flight: Accomplish the corrective actions described in paragraph (c) 
of this AD, per the Accomplishment Instructions in Boeing Service 
Bulletin 767-54A0101, Revision 3, dated September 5, 2002, except as 
provided in paragraph (d) of this AD.

Service Bulletin Revisions

    (h) Accomplishment of the terminating action in paragraph (c)(1) 
of this AD, per the original release of Boeing Service Bulletin 767-
54A0101, dated September 23, 1999; or Revision 2 of Boeing Service 
Bulletin 767-54A0101, dated January 10, 2002; is acceptable for 
compliance with the requirements of this AD. However, as of the 
effective date of this AD, only the actions described in the 
Accomplishment Instructions of Boeing Service Bulletin 767-54A0101, 
Revision 3, dated September 5, 2002, should be used.

Inspections Accomplished Per Previous Issue of Service Bulletin

    (i) Inspections required by paragraphs (a) and (b) of this AD 
that are accomplished before the effective date of this AD per 
Revision 2 of Boeing Service Bulletin 767-54A0101, dated January 10, 
2002; or Revision 3 of Boeing Service Bulletin 767-54A0101, dated 
September 5, 2002; are considered acceptable for compliance with the 
corresponding action specified in this AD.

Alternative Methods of Compliance

    (j) In accordance with 14 CFR 39.19, the Manager, Seattle ACO, 
FAA, is authorized to approve alternative methods of compliance 
(AMOCs) for this AD.

    Issued in Renton, Washington, on December 1, 2003.
Ali Bahrami,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 03-30337 Filed 12-5-03; 8:45 am]

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