[Federal Register Volume 60, Number 201 (Wednesday, October 18, 1995)]
[Rules and Regulations]
[Pages 53862-53864]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 95-25599]
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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39
[Docket No. 95-NM-30-AD; Amendment 39-9403; AD 95-21-16]
Airworthiness Directives; Lockheed Model L-1011-385 Series
Airplanes
AGENCY: Federal Aviation Administration, DOT.
ACTION: Final rule.
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SUMMARY: This amendment adopts a new airworthiness directive (AD),
applicable to all Lockheed Model L-1011-385 series airplanes, that
requires an inspection to detect evidence of sealant around the lug
bushing flanges of certain actuator attach pin assemblies of the main
landing gear (MLG), and replacement of the pin assembly with a
serviceable unit if no sealant is present. This amendment is prompted
by reports of cracks emanating from corrosion pits of the lug bores on
the actuator attach pin assemblies of two MLG's. The actions specified
by this AD are intended to prevent failure of the actuator attach pins
as a result of corrosion and subsequent cracking of the lug bores. Such
failure could result in the MLG failing to extend completely or rapidly
free-falling during extension and causing additional damage to the
landing gear.
DATES: Effective November 17, 1995.
The incorporation by reference of certain publications listed in
the regulations is approved by the Director of the Federal Register as
of November 17, 1995.
ADDRESSES: The service information referenced in this AD 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 Federal
Aviation Administration (FAA), Transport Airplane Directorate, Rules
Docket, 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,
Flight Test 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: A proposal to amend part 39 of the Federal
Aviation Regulations (14 CFR part 39) to include an airworthiness
directive (AD) that is applicable to all Lockheed Model L-1011-385
series airplanes was published in the Federal Register on April 27,
1995 (60 FR 20659). That action proposed to require a one-time
inspection to detect evidence of sealant around the lug bushing flanges
of certain actuator attach pin assemblies of the MLG and, if no sealant
is present, replacement of the pin assembly.
Interested persons have been afforded an opportunity to participate
in the making of this amendment. Due consideration has been given to
the comments received.
One commenter supports the proposed rule.
The Air Transport Association (ATA) of America, on behalf of one of
its members, requests that the FAA extend the compliance time for
replacement of discrepant actuator attach pin assemblies from 6 months
to at least 12 months to coincide with scheduled maintenance
activities. The commenter indicates that replacement parts may not be
procurable within the proposed compliance time. The commenter adds that
it conducts a visual inspection of the affected area every 40 flight
hours due to previous pin failures.
The FAA does not concur with the commenter's request. The FAA has
confirmed that a sufficient quantity of new parts are available to
support the initiation of a replacement program. Additionally, the
service bulletin cited in the AD contains an option that provides for
rework of discrepant pin assemblies for reuse. The FAA is unaware of a
visual inspection procedure that would detect incipient pin failure.
However, the FAA would consider a request for use of such a procedure
as an interim measure, or for an adjustment of the compliance time,
[[Page 53863]]
in accordance with the provisions of paragraph (c) of this AD, provided
that adequate justification is presented to support such a request.
The commenter also contends that this AD action is not warranted.
The commenter indicates that it has not incurred any damage to the
landing gear or aircraft of its fleet resulting from pin failures. The
FAA infers from these remarks that the commenter requests the proposal
be withdrawn. The FAA does not concur with the commenter's position
that this AD is not warranted. Investigation of several reports of
cracked lugs found on the actuator attach pin assemblies of the main
landing gears installed on Model L-1011-385 series airplanes has
revealed that the lugs cracked due to corrosion beneath the bushing
surface on the lug bores. This corrosion may have been caused by the
intrusion of moisture between the lug surface and the bushing flange.
Such corrosion and cracking presents an unsafe condition in these
airplanes, since it could eventually lead to failure of the attach
pins. Failure of the pins could result in the main landing gear failing
to extend completely, or rapidly free-falling during extension and
causing additional damage to the landing gear. The FAA has determined
that this unsafe condition could exist or eventually develop on Model
L-1011-385 series airplanes since the actuator attach pin assemblies
are similar, if not identical, on all models of this series. The FAA
also has determined that an inspection of the affected area, and
correction of discrepancies, must be mandated in order to ensure that
the safety of this fleet is not degraded. The appropriate vehicle for
mandating such action to correct an unsafe condition is the
airworthiness directive.
After careful review of the available data, including the comments
noted above, the FAA has determined that air safety and the public
interest require the adoption of the rule as proposed.
There are approximately 236 Model L-1011-385 series airplanes of
the affected design in the worldwide fleet. The FAA estimates that 117
airplanes of U.S. registry will be affected by this AD, that it will
take approximately 1 work hour per airplane to accomplish the required
actions, and that the average labor rate is $60 per work hour. Based on
these figures, the total cost impact of the AD on U.S. operators is
estimated to be $7,020, or $60 per airplane.
The total cost impact figure discussed above is based on
assumptions that no operator has yet accomplished any of the
requirements of this AD action, and that no operator would accomplish
those actions in the future if this AD were not adopted.
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.
For the reasons discussed above, I certify that this action (1) is
not a ``significant regulatory action'' under Executive Order 12866;
(2) is not a ``significant rule'' under DOT Regulatory Policies and
Procedures (44 FR 11034, February 26, 1979); and (3) 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 final evaluation has been prepared for this action
and it is contained in the Rules Docket. A copy of it may be obtained
from the Rules Docket at the location provided under the caption
ADDRESSES.
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 USC 106(g), 40101, 40113, 44701.
Sec. 39.13 [Amended]
2. Section 39.13 is amended by adding the following new
airworthiness directive:
95-21-16 Lockheed Aeronautical Systems Company: Amendment 39-9403.
Docket 95-NM-30-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 use the authority
provided in paragraph (c) of this AD to request approval from the
FAA. This approval may address either no action, if the current
configuration eliminates the unsafe condition; or different actions
necessary to address the unsafe condition described in this AD. Such
a request should include an assessment of the effect of the changed
configuration on the unsafe condition addressed by this AD. In no
case does the presence of any modification, alteration, or repair
remove any airplane from the applicability of this AD.
Compliance: Required as indicated, unless accomplished
previously.
To prevent failure of the actuator attach pins as a result of
corrosion and subsequent cracking of the lug bores, which could
result in the main landing gear (MLG) failing to extend completely
or rapidly free-falling during extension and causing additional
damage to the landing gear, accomplish the following:
(a) Within 90 days after the effective date of this AD, perform
a one-time inspection to detect evidence of sealant around the lug
bushing flanges of the actuator attach pin assembly, part number
1642699-101, of the MLG, in accordance with Lockheed Service
Bulletin 093-32-256, dated November 11, 1994.
(1) If the inspection reveals that sealant is present, no
further action is required by this AD.
(2) If the inspection reveals that no evidence of sealant is
present, within 6 months after accomplishing the inspection, replace
the actuator attach pin assembly with a serviceable unit in
accordance with Lockheed Service Bulletin 093-32-256, dated November
11, 1994.
(b) As of the effective date of this AD, no actuator attach pin
assembly, part number 1642699-101, shall be installed on the MLG of
any airplane unless that assembly has been inspected in accordance
with the requirements of paragraph (a) of this AD and evidence of
sealant has been found; or unless that assembly has been reworked
and reidentified with the letter ``A'' etched at the end of the
serial number, in accordance with Lockheed Service Bulletin 093-32-
256, dated November 11, 1994.
(c) 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 Aircraft Certification
Office (ACO), FAA, Small Airplane Directorate. 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.
(d) 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.
(e) The inspection and replacement shall be done in accordance
with Lockheed
[[Page 53864]]
Service Bulletin 093-32-256, dated November 11, 1994. 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 (LASSC), Field Support Department, Dept. 693, Zone
0755, 2251 Lake Park Drive, Smyrna, Georgia. 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.
(f) This amendment becomes effective on November 17, 1995.
Issued in Renton, Washington, on October 10, 1995.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 95-25599 Filed 10-17-95; 8:45 am]
BILLING CODE 4910-13-U
