[Federal Register Volume 64, Number 236 (Thursday, December 9, 1999)]
[Proposed Rules]
[Pages 68960-68963]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-31876]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 99-NM-129-AD]
RIN 2120-AA64


Airworthiness Directives; Lockheed Model L-1011-385 Series 
Airplanes

AGENCY: Federal Aviation Administration, DOT.


[[Page 68961]]


ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: This document proposes the adoption of a new airworthiness 
directive (AD) that is applicable to all Lockheed Model L-1011-385 
series airplanes. This proposal would require repetitive inspections to 
detect corrosion or fatigue cracking of certain structural elements of 
the airplane; corrective actions, if necessary; and incorporation of 
certain structural modifications. This proposal is prompted by new 
recommendations related to incidents of fatigue cracking and corrosion 
in transport category airplanes that are approaching or have exceeded 
their economic design goal. The actions specified by the proposed AD 
are intended to prevent corrosion or fatigue cracking of certain 
structural elements, which could result in reduced structural integrity 
of the airplane.

DATES: Comments must be received by January 24, 2000.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 99-NM-129-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.
    The service information referenced in the proposed rule may be 
obtained from Lockheed Martin Aircraft & Logistics Center, 120 Orion 
Street, Greenville, South Carolina 29605. This information may be 
examined at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, 
SW., Renton, Washington; or at the FAA, Small Airplane Directorate, 
Atlanta Aircraft Certification Office, One Crown Center 1895 Phoenix 
Boulevard, suite 450, Atlanta, Georgia.

FOR FURTHER INFORMATION CONTACT: Thomas Peters, Aerospace Engineer, 
Systems and Flight Test Branch, ACE-116A, FAA, Small Airplane 
Directorate, Atlanta Aircraft Certification Office, One Crown Center, 
1895 Phoenix Boulevard, suite 450, Atlanta, Georgia 30349; telephone 
(770) 703-6063; fax (770) 703-6097.

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 notice may be changed in 
light of the comments received.
    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 notice must submit a self-addressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket Number 99-NM-129-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-129-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    In April 1988, a high-cycle transport category airplane 
(specifically, a Boeing Model 737 series airplanes) was involved in an 
accident in which the airplane suffered major structural damage during 
flight. Investigation of this accident revealed that the airplane had 
numerous fatigue cracks and a great deal of corrosion. Subsequent 
inspections conducted by the operator on other high-cycle transport 
category airplanes in its fleet revealed that other airplanes had 
extensive fatigue cracking and corrosion.
    Prompted by the data gained from this accident, the FAA sponsored a 
conference on aging airplanes in June 1988, which was attended by 
representatives from the aviation industry and airworthiness 
authorities from around the world. It became obvious that, because of 
the tremendous increase in air travel, the relatively slow pace of new 
airplane production, and the apparent economic feasibility of operating 
older technology airplanes rather than retiring them, increased 
attention needed to be focused on the aging airplane fleet and 
maintaining its continued operational safety.
    The Air Transport Association (ATA) of America and the Aerospace 
Industries Association (AIA) of America agreed to undertake the task of 
identifying and implementing procedures to ensure the continued 
structural airworthiness of aging transport category airplanes. An 
Airworthiness Assurance Working Group (AAWG) was established in August 
1988, with members representing aircraft manufacturers, operators, 
regulatory authorities, and other aviation industry representatives 
worldwide. The objective of the AAWG was to sponsor ``Task Groups'' to:
    1. Select service bulletins, applicable to each airplane model in 
the transport fleet, to be recommended for mandatory modification of 
aging airplanes;
    2. Develop corrosion-directed inspections and prevention programs;
    3. Review the adequacy of each operator's structural maintenance 
program;
    4. Review and update the Supplemental Inspection Documents (SID); 
and
    5. Assess repair quality.
    The Structures Task Group (STG) assigned to review the Lockheed 
Model L-1011-385 series airplanes was formed in 1988, and included 
operators of Model L-1011-385 series airplanes, Lockheed, the FAA, and 
observers from regulatory agencies. Certain recommendations made by the 
STG (pursuant to Item 1., described previously) are contained in 
Lockheed Service Bulletins 093-51-035, Revision 1, dated December 16, 
1991, and 093-51-040, Revision 1, dated October 1, 1997. The FAA 
previously issued AD 94-05-01, amendment 39-8839 (59 FR 10275, March 4, 
1994), to require the structural inspections and the modifications 
recommended in that document.
    Since the issuance of that AD, the STG has recommended 
accomplishment of certain other structural inspections to detect 
corrosion or fatigue cracking of certain structural elements of the 
airplane, and incorporation of certain structural modifications. 
Corrosion or fatigue cracking of certain structural elements, if not 
detected and corrected, could result in reduced structural integrity of 
the airplane.

Explanation of Relevant Service Information

    The FAA has reviewed and approved Lockheed Tristar L-1011 Service 
Bulletin 093-51-041, dated April 27, 1998 (hereinafter referred to as 
the ``Collector Service Bulletin''). The Collector Service Bulletin 
describes

[[Page 68962]]

certain repetitive inspections to detect corrosion or fatigue cracking 
of certain structural elements of the airplane, including areas around 
the wing/root joint of the fuselage, aft pressure bulkhead of the 
fuselage, and the center section wing box in the wings. The Collector 
Service Bulletin also describes structural modifications of various 
elements of the airplane that have been recommended by the STG, 
including modification of the C1A cargo door, modification of the 
actuator support fitting for the horizontal stabilizer, reinforcement 
of the mid beam longeron at fuselage station 1363 and waterline 168.4, 
and reinforcement of the intermediate spar shear web of the center box 
in the wings. The Collector Service Bulletin also references 
appropriate sources of accomplishment instructions for the structural 
inspections and modifications.
    Accomplishment of the actions specified in the Collector Service 
Bulletin 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 require accomplishment of the actions specified in 
the Collector Service Bulletin described previously, except as 
discussed below.

Other Relevant Rulemaking

    The FAA has previously issued notice of proposed rulemaking (NPRM), 
Rules Docket 98-NM-35-AD (64 FR 34170, June 25, 1999), to require the 
structural inspections and modifications recommended in Lockheed 
Service Bulletin 093-51-040, Revision 1, dated October 1, 1997. 
However, this proposed AD would not affect the requirements of that 
previously issued proposed AD.

Cost Impact

    There are approximately 235 airplanes of the affected design in the 
worldwide fleet. The FAA estimates that 117 airplanes of U.S. registry 
would be affected by this proposed AD.
    It would take approximately 32 work hours per airplane (for Table 
I) and 97 work hours per airplane (for Table II) to accomplish the 
proposed inspections, at an average labor rate of $60 per work hour. 
Based on these figures, the cost impact of the proposed AD on U.S. 
operators is estimated to be $224,640, or $1,920 per airplane, per 
inspection cycle (for Table I), and $680,940, or $5,820 per airplane, 
per inspection cycle (for Table II).
    It would take approximately 614 work hours per airplane to 
accomplish the proposed modifications, at an average labor rate of $60 
per work hour. Required parts would cost approximately $142,275 per 
airplane. Based on these figures, the cost impact of the proposed AD on 
U.S. operators is estimated to be $20,956,455, or $179,115 per 
airplane.
    The cost impact figures discussed above are based on assumptions 
that no operator has yet accomplished any of the proposed requirements 
of this AD action, and that no operator would accomplish those actions 
in the future if this AD were not adopted.

Regulatory Impact

    The regulations proposed herein would not have substantial direct 
effects on the States, on the relationship between the national 
government and the States, or on the distribution of power and 
responsibilities among the various levels of government. Therefore, in 
accordance with Executive Order 12612, it is determined that this 
proposal would not have sufficient federalism implications to warrant 
the preparation of a Federalism Assessment.
    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 adding the following new 
airworthiness directive:

Lockheed: Docket 99-NM-129-AD.

    Applicability: All Model L-1011-385 series airplanes, 
certificated in any category.

    Note 1: This AD applies to each airplane identified in the 
preceding applicability provision, regardless of whether it has been 
modified, altered, or repaired in the area subject to the 
requirements of this AD. For airplanes that have been modified, 
altered, or repaired so that the performance of the requirements of 
this AD is affected, the owner/operator must request approval for an 
alternative method of compliance in accordance with paragraph (d) 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 prevent corrosion or fatigue cracking of certain structural 
elements, which could result in reduced structural integrity of the 
airplane, accomplish the following:

Inspections

    (a) Perform structural inspections to detect corrosion or 
fatigue cracking of certain structural elements of the airplane, in 
accordance with the applicable service bulletins listed under 
``Service Bulletin Number, Revision, and Date'' in Tables I and II 
of Lockheed Tristar L-1011 Service Bulletin 093-51-041, dated April 
27, 1998. Perform the initial inspections at the later of the times 
specified in paragraphs (a)(1) and (a)(2) of this AD. Thereafter, 
repeat the inspections at intervals not to exceed those specified in 
the applicable service bulletin.
    (1) Prior to the threshold specified in the individual service 
bulletin as listed in Table I or II of Lockheed Tristar L-1011 
Service Bulletin 093-51-041, dated April 27, 1998, as applicable.
    (2) Within one repetitive interval after the effective date of 
this AD, as specified in the individual service bulletin listed in 
Table I or II of Lockheed Tristar L-1011 Service Bulletin 093-51-
041, dated April 27, 1998, as applicable.

Corrective Action

    (b) If any cracking or corrosion is detected during any 
inspection required by paragraph (a) of this AD, prior to further 
flight, accomplish the actions specified in paragraph (b)(1), 
(b)(2), (b)(3), or (b)(4) of this AD.
    (1) Repair in accordance with the applicable service bulletin 
referenced in Table I or II of Lockheed Tristar L-1011 Service 
Bulletin 093-51-041, dated April 27, 1998.
    (2) Repair in accordance with the applicable section of the 
Lockheed L-1011 Structural Repair Manual.
    (3) Accomplish the terminating modification in accordance with 
the

[[Page 68963]]

applicable service bulletin referenced in Table I or II of Lockheed 
Tristar L-1011 Service Bulletin 093-51-041, dated April 27, 1998.
    (4) Repair in accordance with a method approved by the Manager, 
Atlanta Aircraft Certification Office (ACO), FAA, Small Airplane 
Directorate.

Terminating Action

    (c) Install the terminating modification referenced in each 
service bulletin listed in Table II of Lockheed Tristar L-1011 
Service Bulletin 093-51-041, dated April 27, 1998; in accordance 
with the applicable service bulletin listed under ``Service Bulletin 
Number, Revision, and Date'' in Table II of Lockheed Tristar L-1011 
Service Bulletin 093-51-041; at the later of the times specified in 
paragraphs (c)(1) and (c)(2) of this AD. Such installation 
constitutes terminating action for the applicable structural 
inspection required by paragraph (a) of this AD.
    (1) Prior to the threshold specified in the applicable service 
bulletin listed in Table II of Lockheed Tristar L-1011 Service 
Bulletin 093-51-041, dated April 27, 1998.
    (2) Within 5 years or 5,000 flight cycles after the effective 
date of this AD, whichever occurs first.

Alternative Methods of Compliance

    (d) 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, Atlanta ACO. Operators shall submit 
their requests through an appropriate FAA Principal Maintenance 
Inspector, who may add comments and then send it to the Manager, 
Atlanta ACO.

    Note 2: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Atlanta ACO.

Special Flight Permits

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

    Issued in Renton, Washington, on December 3, 1999.
D.L. Riggin,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 99-31876 Filed 12-8-99; 8:45 am]
BILLING CODE 4910-13-P