[Federal Register Volume 61, Number 114 (Wednesday, June 12, 1996)]
[Rules and Regulations]
[Pages 29642-29645]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-14692]
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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39
[Docket No. 96-NM-104-AD; Amendment 39-9667; AD 96-12-24]
RIN 2120-AA64
Airworthiness Directives; Lockheed Model L-1011-385 Series
Airplanes
AGENCY: Federal Aviation Administration, DOT.
ACTION: Final rule; request for comments.
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SUMMARY: This amendment adopts a new airworthiness directive (AD) that
is applicable to all Lockheed Model L-1011-385 series airplanes. This
action 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. This AD also provides for an optional
modification which, if accomplished, will defer the initiation of the
inspections for a certain period of time. This amendment is prompted by
a report of fatigue cracking in the web of the rear spar of the wing.
The actions specified in this AD are intended to prevent such fatigue
cracking, which could result in failure of the rear spar of the wing
and consequent fuel spillage.
DATES: Effective June 27, 1996.
The incorporation by reference of certain publications listed in
the regulations is approved by the Director of the Federal Register as
of June 27, 1996.
Comments for inclusion in the Rules Docket must be received on or
before August 12, 1996.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), Transport Airplane Directorate, ANM-103,
Attention: Rules Docket No. 96-NM-104-AD, 1601 Lind Avenue, SW.,
Renton, Washington 98055-4056.
The service information referenced in this AD may be obtained from
Lockheed Aeronautical Systems Support Company, 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,
Atlanta Aircraft Certification Office, Small Airplane Directorate,
Campus Building, 1701 Columbia Avenue, Suite 2-160, College Park,
Georgia; or at the Office of the Federal Register, 800 North Capitol
Street, NW., suite 700, Washington, DC.
FOR FURTHER INFORMATION CONTACT: Thomas Peters, Aerospace Engineer,
Branch, ACE-116A, FAA, Atlanta Aircraft Certification Office, Small
Airplane Directorate, Campus Building, 1701 Columbia Avenue, Suite 2-
160, College Park, Georgia 30337-2748; telephone (404) 305-7367; fax
(404) 305-7348.
SUPPLEMENTARY INFORMATION: The FAA received a report indicating that
fatigue cracking was found on the web of the rear spar of the wing on a
Lockheed Model L-1011-385 series airplane that had accumulated
approximately 18,900 total landings. The crack, which was 24 inches
long, grew rapidly in a downward direction at a 45-degree angle and
stopped behind the trunnion fitting of the main landing gear.
Consequently, the airplane began leaking fuel during final taxi.
Fatigue cracking in the web of the rear spar of the wing can
originate in the fasteners common to the web and the vertical leg of
the upper cap. Such cracking can grow and remain undetected for a
significant period of
[[Page 29643]]
time because the crack can propagate on the interior (fuel side) of the
web before it breaches the aft side (flap side) of the web. Such
fatigue cracking, if not detected and corrected in a timely manner,
could result in failure of the rear spar of the wing and consequent
fuel spillage.
Other Relevant Rules
The FAA previously issued AD 96-07-13, amendment 39-9563 (61 FR
16379, April 15, 1996), which requires various X-ray, eddy current, and
ultrasonic inspections to detect fatigue cracking of certain areas of
the rear spar caps, web, skin, and certain fastener holes; and repair
or modification, if necessary. The inspections are required to be
repeated at intervals of 2,000 flight cycles. That AD was prompted by
reports of fatigue cracks in the caps, web, and skin of the wing rear
spar inboard of inner wing station 346. The actions specified by that
AD are intended to prevent rupture of the rear spar, which could result
in extensive damage to the wing and fuel spillage.
The fatigue cracking that was the subject of the recent in-service
incident, described above, indicates that fatigue cracking in the area
of the web of the rear spar of the wing apparently can occur and
propagate at a faster rate and at a reduced threshold than previously
realized. In light of this, the FAA is considering revising AD 96-07-13
to reduce the repetitive inspection intervals to ensure that fatigue
cracking can be found in a more timely manner. (The FAA indicated this
in the preamble to that AD.)
Explanation of Relevant Service Information
The FAA has reviewed and approved Lockheed L-1011 Service Bulletin
093-57-218, dated April 11, 1996. Part I of the service bulletin
describes procedures for repetitive visual inspections to detect
fatigue cracking and other discrepancies (i.e., corrosion, fastener
looseness, nicks, scratches, or other surface damage) 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. The follow-on actions include repetitive visual
inspections, eddy current surface scan (ECSS) inspections, bolt hole
eddy current (BHEC) inspections, and repair.
Part II of the service bulletin describes procedures for an
optional modification that will allow the initiation of the visual
inspections to be deferred for a period of time. The modification
involves removing certain web-to-cap fasteners, verifying that the
subject fastener holes are free of cracks, cold working the fastener
holes, and replacing the fasteners with oversize fasteners.
Explanation of the Requirements of the Rule
Since an unsafe condition has been identified that is likely to
exist or develop on other Model L-1011-385 series airplanes of the same
type design, this AD is being issued 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. This AD requires
repetitive visual 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 AD also provides for an optional
modification which, if accomplished, will allow the initiation of the
visual inspections to be deferred for a certain period of time. The
actions are required to be accomplished in accordance with the Lockheed
service bulletin described previously.
The inspections that are required by this AD are in addition to--
not in lieu of--those currently required by AD 96-07-13, amendment 39-
9563.
Differences between the Rule and the Referenced Service Information
Operators should note that, although the Lockheed service bulletin
specifies that the manufacturer must be contacted for disposition of
certain conditions, this AD requires that the repair of those
conditions be accomplished in accordance with a method approved by the
Manager, Atlanta Aircraft Certification Office (ACO), FAA, Small
Airplane Directorate.
Determination of Rule's Effective Date
Since a situation exists that requires the immediate adoption of
this regulation, it is found that notice and opportunity for prior
public comment hereon are impracticable, and that good cause exists for
making this amendment effective in less than 30 days.
Comments Invited
Although this action is in the form of a final rule that involves
requirements affecting flight safety and, thus, was not preceded by
notice and an opportunity for public comment, comments are invited on
this rule. Interested persons are invited to comment on this 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 under the caption ADDRESSES. All
communications received on or before the closing date for comments will
be considered, and this rule may be amended in light of the comments
received. Factual information that supports the commenter's ideas and
suggestions is extremely helpful in evaluating the effectiveness of the
AD action and determining whether additional rulemaking action would be
needed.
Comments are specifically invited on the overall regulatory,
economic, environmental, and energy aspects of the rule that might
suggest a need to modify the 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 that
summarizes each FAA-public contact concerned with the substance of this
AD will be filed in the Rules Docket.
Commenters wishing the FAA to acknowledge receipt of their comments
submitted in response to this rule must submit a self-addressed,
stamped postcard on which the following statement is made: ``Comments
to Docket Number 96-NM-104-AD.'' The postcard will be date stamped and
returned to the commenter.
Regulatory Impact
The regulations adopted herein will 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 final
rule does not have sufficient federalism implications to warrant the
preparation of a Federalism Assessment.
The FAA has determined that this regulation is an emergency
regulation that must be issued immediately to correct an unsafe
condition in aircraft, and that it is not a ``significant regulatory
action'' under Executive Order 12866. It has been determined further
that this action involves an emergency regulation under DOT Regulatory
Policies and Procedures (44 FR 11034, February 26, 1979). If it is
determined that this emergency regulation otherwise would be
significant under DOT Regulatory Policies and Procedures, a final
regulatory evaluation will be prepared and placed in the Rules Docket.
A copy of it, if filed, may be obtained from the Rules Docket at the
location provided under the caption ADDRESSES.
[[Page 29644]]
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by
reference, Safety.
Adoption of the Amendment
Accordingly, pursuant to the authority delegated to me by the
Administrator, the Federal Aviation Administration amends 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:
96-12-24 Lockheed: Amendment 39-9667. Docket 96-NM-104-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
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 (e) 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:
(a) Perform a visual inspection to detect signs of cracking and
other discrepancies (i.e., corrosion, fastener looseness, nicks,
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; 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
within 10 days after the effective date of this AD, whichever occurs
later.
(2) For airplanes on which the wing rear spar has been modified
prior to the effective date of this AD 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, 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 the effective date of this AD, 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.-
(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. -
(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 1 of the service bulletin. -
(2) If any cracking is confirmed, prior to further flight, repair
it in accordance with the service bulletin. -
(d) Accomplishment of the modification specified in Part II of the
Accomplishment Instructions of Lockheed Service Bulletin 093-57-218,
dated April 11, 1996, and in accordance with that service bulletin,
allows the visual inspections required by paragraph (a) of this AD to
be deferred for the period specified in paragraph (d)(2) of this AD. -
(1) If any condition (i.e., number of fasteners per stiffener bay,
or cracking) is identified during the accomplishment of the
modification that 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. -
(2) 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 the service bulletin. -
(e) 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, 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.
-(f) 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. -
(g) The actions shall be done in accordance with Lockheed L-1011
Service Bulletin 093-57-218, dated April 11, 1996. This incorporation
by reference was approved by the Director of the Federal Register in
accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be
obtained from Lockheed Aeronautical Systems Support Company, Field
Support Department, Dept. 693, Zone 0755, 2251 Lake Park Drive, Smyrna,
Georgia 30080. Copies may be inspected at the FAA, Transport Airplane
Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the FAA,
Atlanta Aircraft Certification Office, Small Airplane Directorate,
Campus Building, 1701 Columbia Avenue, Suite 2-160, College Park,
Georgia; or at the Office of the Federal Register, 800 North Capitol
Street, NW., suite 700, Washington, DC. -
(h) This amendment becomes effective on June 27, 1996.
[[Page 29645]]
Issued in Renton, Washington, on June 5, 1996.
James V. Devany,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 96-14692 Filed 6-11-96; 8:45 am]
BILLING CODE 4910-13-U