[Federal Register Volume 62, Number 227 (Tuesday, November 25, 1997)]
[Proposed Rules]
[Pages 62728-62732]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-30857]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 97-NM-11-AD]
RIN 2120-AA64
Airworthiness Directives; Lockheed Model L-1011-385 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 Lockheed Model L-1011-
385 series airplanes, that currently requires inspections to detect
cracking and other discrepancies of certain web-to-cap fasteners of the
rear spar between inner wing stations (IWS) 310 and 343, and of the web
area around those fasteners; and various follow-on actions. That AD
also provides for an optional modification, which, if accomplished,
would defer the initiation of the inspections for a certain period of
time. This action would require accomplishment of the previously
optional modification. This proposal is prompted by an FAA
determination that the optional terminating modification specified in
the existing AD must be accomplished within a specified period of time
to ensure an acceptable level of safety of the affected fleet. The
actions specified by the proposed AD are intended to prevent fatigue
cracking in the web of the rear spar of the wing, which could result in
failure of the rear spar of the wing and consequent fuel spillage.
DATES: Comments must be received by January 5, 1998.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), Transport Airplane Directorate, ANM-103,
Attention: Rules Docket No. 97-NM-11-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 Aeronautical Systems Support Company (LASSC),
Field Support Department, Dept. 693, Zone 0755, 2251 Lake Park Drive,
Smyrna, Georgia 30080. 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 30337-2748;
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
[[Page 62729]]
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 97-NM-11-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-103, Attention: Rules
Docket No. 97-NM-11-AD, 1601 Lind Avenue, SW., Renton, Washington
98055-4056.
Discussion
On June 5, 1996, the FAA issued AD 96-12-24, amendment 39-9667 (61
FR 29642, June 12, 1996), applicable to all Lockheed Model L-1011-385
series airplanes, to require repetitive visual inspections to detect
cracking and other discrepancies of certain web-to-cap fasteners of the
rear spar between inner wing stations (IWS) 310 and 343, and of the web
area around those fasteners; and various follow-on actions. That action
also provides for an optional modification, which, if accomplished,
would allow the initiation of the visual inspections to be deferred for
a certain period of time. That action was prompted by a report of
fatigue cracking in the web of the rear spar of the wing. The
requirements of that AD are intended to prevent such fatigue cracking,
which could result in failure of the rear spar of the wing and
consequent fuel spillage.
Actions Since Issuance of Previous Rule
Since the issuance of AD 96-12-24, the FAA has determined that the
optional terminating modification specified in the existing AD must be
required to be accomplished within a specified period of time to reduce
the possibility of fatigue cracking remaining undetected and to ensure
an acceptable level of safety of the affected fleet.
Lockheed Service Bulletin 093-57-218, which is referenced in the
existing AD as the appropriate source of service information, does not
recommend a limit on the number of inspections to be accomplished prior
to installation of the modification. Table I of the service bulletin
recommends that the inspections be accomplished at short repetitive
intervals, which range from 60 to 180 landings.
The FAA finds that the possibility of maintenance errors during
inspection could result in a net degradation in airplane safety if the
inspections are performed in accordance with the schedule set forth in
the service bulletin. The FAA considers that accomplishment of
continuous inspections at the short inspection intervals specified in
the service bulletin increases the risk that fatigue cracking could
remain undetected. Consequently, the FAA has determined that the
previously optional modification must be accomplished to ensure an
acceptable level of safety. Following accomplishment of the
modification, inspection must resume after the accumulation of no more
than 5,000 landings.
Explanation of Relevant Service Information
Since the issuance of AD 96-12-24, the FAA has reviewed and
approved Lockheed Service Bulletin 093-57-218, Revision 1, dated
September 9, 1996. This service bulletin revision describes procedures
for inspections to detect cracking and other discrepancies of certain
web-to-cap fasteners of the rear spar, and for modification of the web-
to-cap fastener holes, in an expanded area of the IWS (i.e., IWS 299
through IWS 343). In all other respects, Revision 1 of the service
bulletin is essentially the same as the original issue.
Additionally, the FAA has reviewed and approved several other
Lockheed service bulletins, listed below, which provide options for
accomplishment of certain modifications in lieu of that specified in
Lockheed Service Bulletin 093-57-218. If accomplished, these
modifications would allow the repetitive inspections to be deferred for
specified periods of time.
For Lockheed Model L-1011-385-3 series airplanes:
Lockheed Service Bulletin 093-57-203, Revision 3, dated
October 28, 1991; as amended by Change Notifications 093-57-203, R3-
CN1, dated June 22, 1992; 093-57-203, R3-CN2, dated February 15, 1993;
and 093-57-203, R3-CN3, dated September 15, 1994.
Lockheed Service Bulletin 093-57-215, dated April 11,
1996. For Lockheed Model L-1011-385-1 series airplanes:
Lockheed Service Bulletin 093-57-184, Revision 6, dated
October 28, 1991, as amended by Change Notifications 093-57-184, R6-
CN1, dated June 22, 1992, and 093-57-184, R6-CN2, dated December 14,
1992.
Lockheed Service Bulletin 093-57-184, Revision 7, dated
December 6, 1994, as amended by Change Notifications 093-57-184, R7-
CN1, dated August 22, 1995, 093-57-184, R7-CN2, dated February 20,
1996, and 093-57-184, R7-CN3, dated April 4, 1996; and Lockheed Service
Bulletin 093-57-212, dated November 14, 1994, as amended by Change
Notification 093-57-212, CN1, dated September 27, 1995.
Lockheed Service Bulletin 093-57-196, Revision 5, dated
October 28, 1991, as amended by Change Notification 093-57-196, R5-CN1,
dated June 22, 1992; and Lockheed Service Bulletin 093-57-212, dated
November 14, 1994, as amended by Change Notification 093-57-212, CN1,
dated September 27, 1995.
Lockheed Service Bulletin 093-57-196, Revision 6, dated
December 6, 1994, as amended by Change Notification 093-57-196, R6-CN1,
dated August 22, 1995, 093-57-196, R6-CN2, dated February 20, 1996, and
093-57-196, R6-CN3, dated May 21, 1996.
A description of each service bulletin follows:
Lockheed Service Bulletin 093-57-203. This service
bulletin describes procedures for modification of the upper and lower
caps of the rear spar between IWS 228 and IWS 346. The modification
involves removal of fasteners, reaming of fastener holes, performing an
eddy current inspection, removing crack indications, cold working the
holes, installing oversize fasteners, adding angle reinforcements to
the upper caps, and adding doublers at the rear spar and main landing
gear fitting joint.
Lockheed Service Bulletin 093-57-215: This service
bulletin describes procedures for modification of the left and right
wing rear spars. The modification entails cold working the fasteners,
installing new oversized fasteners (if necessary), adding structure
reinforcements to the lower caps, and adding new upper caps and webs at
the rear spar and main landing gear fitting joint.
Lockheed Service Bulletins 093-57-184 and 093-57-212.
These service
[[Page 62730]]
bulletins describe procedures for modification of the inboard and
outboard rear spars, respectively. Modification of the inboard spar web
entails removing the entire web inboard to IWS 228.774 and replacing it
with a new web portion; adding new upper caps and stiffeners in both
wings, cold working certain fastener holes, and removing certain
existing fasteners for eddy current hole inspection. Modification of
the outboard spar web involves performing an eddy current inspection of
the fastener holes, cold working specific fastener holes (if no
cracking is found), repairing any crack found, and installing a new
outboard web section.
Lockheed Service Bulletin 093-57-196. This service
bulletin describes procedures for modification of the inboard rear
spar, which includes removing the entire web inboard to IWS 228.774 and
replacing it with a new web portion; adding new upper caps and
stiffeners in both wings, cold working certain fastener holes, and
removing certain existing fasteners for eddy current hole inspection.
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 96-12-24 to continue to require
inspections to detect cracking and other discrepancies of certain web-
to-cap fasteners of the rear spar between IWS 310 and IWS 343, and of
the web area around those fasteners; and various follow-on actions.
This proposed AD would require accomplishment of the previously
optional modification, which, when accomplished, will defer the
initiation of the inspections for a certain period of time. The
proposed AD also provides for additional options for accomplishment of
the previously optional modification, which also defer the inspections
for certain specified periods of time. The actions would be required to
be accomplished in accordance with the service bulletin described
previously.
Differences Between the Service Bulletin and This Proposed AD
Operators should note that Revision 1 of Lockheed Service Bulletin
093-57-218 expands the inspection area to include IWS 299 through IWS
310. However, the FAA has determined that the various X-ray, eddy
current, and ultrasonic inspections of certain areas of the rear spar
caps, web, skin, and fastener holes required by AD 96-07-13, amendment
39-9563 (61 FR 16379, April 15, 1996), adequately address fatigue
cracking in the expanded area specified in Revision 1 of the service
bulletin. Therefore, this proposed AD does not require inspection of
that expanded area. However, the FAA finds that accomplishment of the
proposed modification in the expanded area, as recommended in the
service bulletin, is necessary to ensure an acceptable level of safety.
Cost Impact
There are approximately 235 Lockheed Model L-100-385 series
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.
The actions that are currently required by AD 96-12-24 take
approximately 13 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 $91,260, or $780 per airplane.
The new actions that are proposed in this AD action would take
approximately 100 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 proposed requirements of this AD on U.S. operators is
estimated to be $702,000, or $6,000 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.
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 removing amendment 39-9667 (61 FR
29642, June 12, 1996), and by adding a new airworthiness directive
(AD), to read as follows:
Lockheed: Docket 97-NM-11-AD. Supersedes AD 96-12-24, Amendment 39-
9667.
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
otherwise 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 (h)(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 prevent fatigue cracking on the web of the rear spar of the
wing, which could result in failure of the rear spar of the wing and
consequent fuel spillage, accomplish the following:
Restatement of Requirements of AD 96-12-24
(a) Perform a visual inspection to detect signs of cracking and
other discrepancies (i.e., corrosion, fastener looseness, nicks,
[[Page 62731]]
scratches, or other surface damage) of the web-to-cap fasteners of
the rear spar between inner wing stations (IWS) 310 and 343, as
specified in Figure 2 of Lockheed Service Bulletin 093-57-218, dated
April 11, 1996, or Revision 1, dated September 9, 1996; and of the
web area around those fasteners; in accordance with Part I of the
Accomplishment Instructions of that service bulletin. Perform the
inspection at the applicable time specified in paragraph (a)(1) or
(a)(2) of this AD.
(1) Except as provided by paragraph (a)(2) of this AD: Perform
the initial inspection prior to the accumulation of the number of
landings specified as the ``inspection threshold'' in Table I of
Lockheed Service Bulletin 093-57-218, dated April 11, 1996, or
Revision 1, dated September 9, 1996, or within 10 days after June
27, 1996 (the effective date of AD 96-12-24), whichever occurs
later.
(2) For airplanes on which the wing rear spar has been modified
prior to June 27, 1996, in accordance with one of the Lockheed
service bulletins listed in paragraph (a)(2)(ii) of this AD,
accomplish the inspection as follows:
(i) Perform the initial inspection prior to the accumulation of
the number of landings specified as the ``inspection threshold'' in
Table I of Lockheed Service Bulletin 093-57-218, dated April 11,
1996, or Revision 1, dated September 9, 1996, calculated from the
time the wing rear spar was modified (rather than from the date of
manufacture of the airplane), or within 10 days after June 27, 1996,
whichever occurs later.
(ii) This paragraph applies to airplanes on which the wing rear
spar has been modified in accordance with one of the following
service bulletins:
Lockheed Service Bulletin 093-57-184, Revision 6, dated
October 28, 1991, or Revision 7, dated December 6, 1994; or
Lockheed Service Bulletin 093-57-196, Revision 5, dated
October 28, 1991, or Revision 6, dated December 6, 1994; or
Lockheed Service Bulletin 093-57-203, Revision 3, dated
October 28, 1991, or Revision 4, dated March 27, 1995; or
Lockheed Service Bulletin 093-57-215, dated April 11,
1996.
(b) If no sign of cracking or other discrepancy is found during
the inspection required by paragraph (a) of this AD, repeat that
inspection thereafter at intervals not to exceed the number of
landings specified as the ``repeat visual inspection interval'' in
Table I of Lockheed Service Bulletin 093-57-218, dated April 11,
1996, or Revision 1, dated September 9, 1996.
(c) If any sign of cracking is found during an inspection
required by paragraph (a) or (b) of this AD, prior to further
flight, perform either eddy current surface scan (ECSS) inspections,
or bolt hole eddy current (BHEC) inspections, as appropriate, to
confirm cracking, in accordance with Lockheed Service Bulletin 093-
57-218, dated April 11, 1996, or Revision 1, dated September 9,
1996.
(1) If no cracking is confirmed, repeat the inspection specified
in paragraph (a) of this AD at intervals not to exceed the number of
landings specified as the ``repeat visual inspection interval'' in
Table I of the service bulletin.
(2) If any cracking is confirmed, prior to further flight,
repair it in accordance with the service bulletin.
New Requirements of This AD
(d) Except as provided by paragraph (e) or (f) of this AD, as
applicable: Within 12 months after the effective date of this AD,
modify the web-to-cap fastener holes of the rear spar between IWS
299 and IWS 343 in accordance with Part II of the Accomplishment
Instructions of Lockheed Service Bulletin 093-57-218, Revision 1,
dated September 9, 1996. Within 5,000 landings following
accomplishment of the modification, perform the visual inspection
required by paragraph (a) of this AD. Thereafter, repeat that
inspection at intervals not to exceed the number of landings
specified as the ``repeat visual inspection interval'' in Table I of
Lockheed Service Bulletin 093-57-218, Revision 1, dated September 9,
1996.
(e) For Model L-1011-385-3 series airplanes: Accomplishment of
the modifications specified in paragraph (e)(1) or (e)(2) of this
AD, within 12 months after the effective date of this AD,
constitutes an acceptable alternative to the modification specified
in paragraph (d) of this AD.
(1) Modify the upper and lower caps of the rear spar between IWS
228 and IWS 346 in accordance with Part I of the Accomplishment
Instructions of Lockheed Service Bulletin 093-57-203, Revision 3,
dated October 28, 1991. Within 5,000 landings following
accomplishment of the modification, perform the visual inspection
required by paragraph (a) of this AD. Thereafter, repeat that
inspection at intervals not to exceed the number of landings
specified as the ``repeat visual inspection interval'' in Table I of
Lockheed Service Bulletin 093-57-218, Revision 1, dated September 9,
1996. Or
(2) Modify the left and right wing rear spars in accordance with
the Accomplishment Instructions of Lockheed Service Bulletin 093-57-
215, dated April 11, 1996. Within the thresholds specified in Table
I of Lockheed Service Bulletin 093-57-218, Revision 1, dated
September 9, 1996 (calculated from the date of installation of
Lockheed Service Bulletin 093-57-215, dated April 11, 1996), perform
the visual inspection required by paragraph (a) of this AD.
Thereafter, repeat that inspection at intervals not to exceed the
number of landings specified as the ``repeat visual inspection
interval'' in Table I of Lockheed Service Bulletin 093-57-218,
Revision 1, dated September 9, 1996.
(f) For Model L-1011-385-1 series airplanes: Accomplishment of
the modifications specified in paragraph (f)(1) or (f)(2) of this
AD, within 12 months after the effective date of this AD,
constitutes an acceptable alternative to the modification specified
in paragraph (d) of this AD.
(1) Modify the inboard and outboard rear spars in accordance
with the Accomplishment Instructions of Lockheed Service Bulletin
093-57-184, Revision 6, dated October 28, 1991, or Revision 7, dated
December 6, 1994; and Lockheed Service Bulletin 093-57-212, dated
November 14, 1994, as amended by Change Notification CN1, dated
September 27, 1995. Within the thresholds specified in Table I of
Lockheed Service Bulletin 093-57-218, Revision 1, dated September 9,
1996 (calculated from the date of installation of Lockheed Service
Bulletin 093-57-184, Revision 6, dated October 28, 1991, or Revision
7, dated December 6, 1994; and Lockheed Service Bulletin 093-57-212,
dated November 14, 1994, as amended by Change Notification CN1,
dated September 27, 1995), perform the visual inspection required by
paragraph (a) of this AD. Thereafter, repeat that inspection at
intervals not to exceed the number of landings specified as the
``repeat visual inspection interval'' in Table I of Lockheed Service
Bulletin 093-57-218, Revision 1, dated September 9, 1996. Or
(2) Modify the inboard and outboard rear spars in accordance
with the Accomplishment Instructions of Lockheed Service Bulletin
093-57-196, Revision 5, dated October 28, 1991, or Revision 6, dated
December 6, 1994; and Lockheed Service Bulletin 093-57-212, dated
November 14, 1994, as amended by Change Notification CN1, dated
September 27, 1995. Within the thresholds specified in Table I of
Lockheed Service Bulletin 093-57-218, Revision 1, dated September 9,
1996 (calculated from the date of installation of Lockheed Service
Bulletin 093-57-196, Revision 5, dated October 28, 1991, or Revision
6, dated December 6, 1994; and Lockheed Service Bulletin 093-57-212,
dated November 14, 1994, as amended by Change Notification CN1,
dated September 27, 1995), perform the visual inspection required by
paragraph (a) of this AD. Thereafter, repeat that inspection at
intervals not to exceed the number of landings specified as the
``repeat visual inspection interval'' in Table I of Lockheed Service
Bulletin 093-57-218, Revision 1, dated September 9, 1996.
(g) If any condition (i.e., number of fasteners per stiffener
bay, or cracking) is identified during the accomplishment of the
modification specified in Lockheed Service Bulletin 093-57-218,
Revision 1, dated September 9, 1996, and that condition exceeds the
limits specified in paragraph B.(3) of Part II of the Accomplishment
Instructions of the service bulletin, prior to further flight,
repair in accordance with a method approved by the Manager, Atlanta
Aircraft Certification Office (ACO), FAA, Small Airplane
Directorate.
(h)(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, 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.
(2) Alternative methods of compliance, approved previously in
accordance with AD 96-12-24, amendment 39-9667, are approved as
alternative methods of compliance with paragraph (d) of this AD.
Note 2: Information concerning the existence of approved
alternative methods of compliance with this AD, if any, may be
obtained from the Atlanta ACO.
[[Page 62732]]
(i) 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 November 18, 1997.
James V. Devany,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 97-30857 Filed 11-24-97; 8:45 am]
BILLING CODE 4910-13-U
