[Federal Register Volume 59, Number 168 (Wednesday, August 31, 1994)]
[Unknown Section]
[Page 0]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 94-21482]
[[Page Unknown]]
[Federal Register: August 31, 1994]
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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39
[Docket No. 94-NM-130-AD; Amendment 39-9020; AD 94-18-07]
Airworthiness Directives; McDonnell Douglas Model DC-10 and Model
MD-11 Series Airplanes and KC-10A (Military) Airplanes
AGENCY: Federal Aviation Administration, DOT.
ACTION: Final rule; request for comments.
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SUMMARY: This amendment supersedes two existing airworthiness
directives (AD), applicable to all McDonnell Douglas Model DC-10 series
airplanes and KC-10A (military) airplanes and certain Model MD-11
series airplanes, that currently require inspections to determine the
serial numbers and to detect defects in the upper and lower lock links
on the nose landing gear (NLG), and rework or replacement of any
defective link with a serviceable link. This amendment requires
additional inspections and provides optional terminating action for
those inspections. This amendment is prompted by additional reports of
defects found on links that are required to be inspected by the
existing AD's. The actions specified in this AD are intended to prevent
collapse of the NLG.
DATES: Effective September 15, 1994.
The incorporation by reference of certain publications listed in
the regulations is approved by the Director of the Federal Register as
of September 15, 1994.
Comments for inclusion in the Rules Docket must be received on or
before October 31, 1994.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), Transport Airplane Directorate, ANM-103,
Attention: Rules Docket No. 94-NM-130-AD, 1601 Lind Avenue, SW.,
Renton, Washington 98055-4056.
The service information referenced in this AD may be obtained from
McDonnell Douglas Corporation, P.O. Box 1771, Long Beach, California
90801-1771, Attention: Business Unit Manager, Technical Administrative
Support, Dept. L51, M.C. 2-98. This information may be examined at the
FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton,
Washington; or at the FAA, Transport Airplane Directorate, Los Angeles
Aircraft Certification Office, 3229 East Spring Street, Long Beach,
California; or at the Office of the Federal Register, 800 North Capitol
Street, NW., suite 700, Washington, DC.
FOR FURTHER INFORMATION CONTACT: For Model DC-10 series airplanes and
Model KC-10A (military) airplanes: Maureen Moreland, Aerospace
Engineer, Airframe Branch, ANM-121L, FAA, Transport Airplane
Directorate, Los Angeles Aircraft Certification Office, 3229 East
Spring Street, Long Beach, California 90806-2425; telephone (310) 988-
5238; fax (310) 988-5210.
For Model MD-11 series airplanes: Wahib Mina, Aerospace Engineer,
Airframe Branch, ANM-121L, FAA, Transport Airplane Directorate, Los
Angeles Aircraft Certification Office, 3229 East Spring Street, Long
Beach, California 90806-2425; telephone (310) 988-5324; fax (310) 988-
5210.
SUPPLEMENTARY INFORMATION: In April 1994, the FAA issued AD 94-09-01,
amendment 39-8889 (59 FR 18722, April 20, 1994), applicable to
McDonnell Douglas Model MD-11 series airplanes, and AD 94-09-17,
amendment 39-8906 (59 FR 23144, May 5, 1994), applicable to McDonnell
Douglas Model DC-10 series airplanes and KC-10A (military) airplanes.
These AD's require inspections to determine the serial numbers and to
detect defects in the upper and lower lock links on the nose landing
gear (NLG), and rework or replacement of any defective link found. Both
actions were prompted by a report of cracking and subsequent failure of
an upper lock link on the center landing gear (CLG) on a McDonnell
Douglas Model MD-11 series airplane; the cracking and failure were
attributed to forging defects in the lock links.
The CLG lower lock links, NLG upper lock links, and NLG lower lock
links are similar in design to CLG upper lock links and are
manufactured by the same forging supplier; therefore, these lock links
may have the same forging defects. These lock links also may be
installed on Model DC-10 series airplanes and KC-10A (military)
airplanes. Consequently, AD 94-09-17 was issued to address the lock
links installed on Model DC-10 series airplanes and KC-10A (military)
airplanes.
Failure of the lock links on the CLG would result in collapse of
the CLG; collapse of the CLG does not present an unsafe condition.
Cracking and subsequent failure of the NLG lock links, if not
corrected, could result in collapse of the NLG, which could reduce
controllability of the airplane during takeoff or landing. The actions
required by AD 94-09-01 and AD 94-09-17 are intended to prevent
collapse of the NLG.
Since the issuance of those AD's, the FAA has received reports of
two additional defective lock links with three cracks that have been
attributed to forging defects. These defective lock links were found on
the NLG's on Model DC-10 and MD-11 series airplanes during
accomplishment of the inspections required by the existing AD's.
Subsequently, the FAA has determined that defects in the lock links may
exist as a result of improperly accomplished fluorescent penetrant
inspections of the entire lock link during manufacturing. After
manufacture of a lock link, its material is etched and a fluorescent
penetrant inspection is performed to detect forging defects. The
fluorescent penetrant inspections accomplished on the affected lock
links were performed without accomplishment of the etching process.
Forging defects in these lock links could result in eventual failure of
the lock link and subsequent collapse of the NLG.
The FAA has reviewed and approved McDonnell Douglas DC-10 Alert
Service Bulletin A32-238 and MD-11 Alert Service Bulletin A32-47, both
dated July 15, 1994, that describe procedures for visual inspections to
determine the serial numbers of the upper and lower lock links on the
NLG. The alert service bulletins also describe three phases of
inspections:
1. Phase I inspections involve an on-aircraft eddy current
inspection to detect defects in the upper and lower lock links on the
NLG. These inspections are designed to detect particular defects in
areas of the highest probability of forging flaws.
2. Phase II inspections entail expanded off-aircraft eddy current
inspections to detect defects of the upper and lower lock links on the
NLG. These inspections are more extensive than Phase I inspections and
are designed to detect defects in an expanded area where flaws could
exist.
3. Phase III inspections include an off-aircraft fluorescent
penetrant inspection to detect defects in the upper and lower lock
links on the NLG. These inspections include etching of the link
material prior to accomplishing a fluorescent penetrant inspection.
Accomplishment of Phase III inspections will ensure that all forging
defects are detected.
For NLG's on which a defective lock link is found, the alert
service bulletins describe procedures for rework of the defective lock
link, or replacement of the defective lock link with a serviceable lock
link. Accomplishment of the fluorescent penetrant inspection and rework
of any defective lock link found during that inspection, or replacement
of any defective lock link found during that inspection, eliminates the
need for the eddy current inspections specified in the alert service
bulletins.
Since an unsafe condition has been identified that is likely to
exist or develop on other airplanes of this same type design, this AD
supersedes AD 94-09-01 and AD 94-09-17 to require inspections to
determine the serial numbers and to detect defects in the upper and
lower lock links on the NLG, and rework of any defective lock link, or
replacement of any defective lock link with a serviceable lock link.
This AD also provides an optional terminating action for the required
inspections. The actions are required to be accomplished in accordance
with the alert service bulletins described previously.
This AD also requires that operators report inspection findings to
the FAA in the event any defect is found during any inspection.
The FAA is considering further rulemaking to require accomplishment
of the optional terminating action specified in this AD. However, the
proposed compliance time is sufficiently long so that notice and time
for public comment would not be impracticable.
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 94-NM-130-AD.'' The postcard will be date stamped and
returned to the commenter.
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.
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. App. 1354(a), 1421 and 1423; 49 U.S.C.
106(g); and 14 CFR 11.89.
Sec. 39.13 [Amended] -
2. Section 39.13 is amended by removing amendments 39-8889 (59 FR
18722, April 20, 1994) and 39-8906 (59 FR 23144, May 5, 1994), and by
adding a new airworthiness directive (AD), amendment 39-9020, to read
as follows:
94-18-07 McDonnell Douglas: Amendment 39-9020. Docket 94-NM-130-AD.
Supersedes AD 94-09-01, Amendment 39-8889; and AD 94-09-17,
Amendment 39-8906.
-Applicability: All Model DC-10 series airplanes and Model KC-
10A (military) airplanes; and Model MD-11 series airplanes, as
listed in McDonnell Douglas MD-11 Alert Service Bulletin A32-47,
dated July 15, 1994; certificated in any category. -
Compliance: Required as indicated, unless accomplished
previously.
-Note 1: Visual inspections of the lock links, as required by
paragraph (a) of this AD, and eddy current inspections of the lock
links, as required by paragraph (b)(1) of this AD, that have been
accomplished prior to the effective date of this AD in accordance
with McDonnell Douglas DC-10 Alert Service Bulletin A32-237, dated
April 11, 1994; or McDonnell Douglas MD-11 Alert Service Bulletin
A32-44, dated March 22, 1994, or Revision 1, dated June 16, 1994; as
applicable; are considered acceptable for compliance with the
applicable action specified in this amendment.
-To prevent collapse of the nose landing gear (NLG), accomplish
the following: -
(a) Within 30 days after the effective date of this AD, perform
a visual inspection to determine the serial number of the upper lock
links, part number ACG7396-1, and the lower lock links, part number
ACG7237-1, on the NLG, in accordance with McDonnell Douglas DC-10
Alert Service Bulletin A32-238, dated July 15, 1994; or McDonnell
Douglas MD-11 Alert Service Bulletin A32-47, dated July 15, 1994; as
applicable. -
(b) If the serial number of the lock link coincides with any of
the suspect serial numbers listed in McDonnell Douglas DC-10 Alert
Service Bulletin A32-238, dated July 15, 1994; or McDonnell Douglas
MD-11 Alert Service Bulletin A32-47, dated July 15, 1994; as
applicable; accomplish paragraphs (b)(1) and (b)(2) of this AD in
accordance with the alert service bulletin. -
(1) Prior to further flight, perform an eddy current inspection
to detect defects in the lock link in accordance with Phase I
(``Eddy Current Inspection--On Aircraft'') of the Accomplishment
Instructions of the applicable alert service bulletin. -
(2) Perform an expanded eddy current inspection to detect
defects in the lock link, in accordance with Phase II (``Expanded
Eddy Current Inspection--Off Aircraft'') of the Accomplishment
Instructions of the applicable alert service bulletin at the time
specified in paragraph (b)(2)(i) or (b)(2)(ii) of this AD, as
applicable. -
(i) For Model DC-10 series airplanes and Model KC-10A airplanes:
Inspect prior to the accumulation of 450 landings after the
effective date of this AD, and thereafter at intervals not to exceed
450 landings. -
(ii) For Model MD-11 series airplanes: Inspect prior to the
accumulation of 330 landings after the effective date of this AD,
and thereafter at intervals not to exceed 330 landings. -
(c) If any defect is found during any inspection required by
paragraph (b) of this AD, prior to further flight, accomplish either
paragraph (c)(1) or (c)(2) of this AD in accordance with McDonnell
Douglas DC-10 Alert Service Bulletin A32-238, dated July 15, 1994;
or McDonnell Douglas MD-11 Alert Service Bulletin A32-47, dated July
15, 1994; as applicable. -
(1) Rework the lock link; or -
(2) Replace the defective lock link with a serviceable lock link
that has been inspected in accordance with paragraphs (a) and (b) of
this AD and, if the lock link was found to contain any defect, that
has been reworked in accordance with paragraph (c)(1) of this AD. -
(d) Accomplishment of a fluorescent penetrant inspection to
detect defects of the lock links, in accordance with Phase III
(``Fluorescent Penetrant Inspection--Off Aircraft'') of the
Accomplishment Instructions of McDonnell Douglas DC-10 Alert Service
Bulletin A32-238, dated July 15, 1994; or McDonnell Douglas MD-11
Alert Service Bulletin A32-47, dated July 15, 1994; as applicable;
constitutes terminating action for the inspections required by
paragraph (b) of this AD. -
(e) If any defect is found during an inspection performed in
accordance with paragraph (d) of this AD, prior to further flight,
accomplish either paragraph (e)(1) or (e)(2) of this AD in
accordance with McDonnell Douglas DC-10 Alert Service Bulletin A32-
238, dated July 15, 1994; or McDonnell Douglas MD-11 Alert Service
Bulletin A32-47, dated July 15, 1994; as applicable. -
(1) Rework the lock link; or -
(2) Replace the defective lock link with a serviceable lock link
that has been inspected in accordance with paragraphs (a) and (b) of
this AD and, if the lock link was found to contain any defect, that
has been reworked in accordance with paragraph (e)(1) of this AD. -
(f) As of the effective date of this AD, no person shall install
an upper lock link, part number ACG7396-1, or a lower lock link,
part number ACG7237-1, on the NLG of any airplane unless that lock
link has been inspected in accordance with paragraphs (a) and (b) of
this AD and reworked, as necessary, in accordance with paragraph
(c)(1) or (e)(1) of this AD. -
(g) Within 30 days after any defect is found during any
inspection required by this AD, submit a report of inspection
findings to the Manager, Los Angeles Aircraft Certification Office
(ACO), 3229 East Spring Street, Long Beach, California 90806-2425;
fax (310) 988-5210. The report must include a description of the
defect found, the part number of the defective lock link, the serial
number of the defective lock link, the number of landings on the
defective lock link, and the serial number of the airplane.
Information collection requirements contained in this regulation
have been approved by the Office of Management and Budget (OMB)
under the provisions of the Paperwork Reduction Act of 1980 (44
U.S.C. 3501 et seq.) and have been assigned OMB Control Number 2120-
0056. -
(h) 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, Los Angeles ACO, FAA, Transport
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, Los Angeles ACO.
-Note 2: Information concerning the existence of approved
alternative methods of compliance with this AD, if any, may be
obtained from the Los Angeles ACO.
-(i) Special flight permits may be issued in accordance with
Secs. 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. -
(j) The actions shall be done in accordance with McDonnell
Douglas DC-10 Alert Service Bulletin A32-238, dated July 15, 1994;
and McDonnell Douglas MD-11 Alert Service Bulletin A32-47, dated
July 15, 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 McDonnell Douglas
Corporation, P.O. Box 1771, Long Beach, California 90801-1771,
Attention: Business Unit Manager, Technical Administrative Support,
Dept. L51, M.C. 2-98. Copies may be inspected at the FAA, Transport
Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or
at the FAA, Transport Airplane Directorate, Los Angeles Aircraft
Certification Office, 3229 East Spring Street, Long Beach,
California; or at the Office of the Federal Register, 800 North
Capitol Street, NW., suite 700, Washington, DC. -
(k) This amendment becomes effective on September 15, 1994.
Issued in Renton, Washington, on August 25, 1994.
N.B. Martenson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 94-21482 Filed 8-30-94; 8:45 am]
BILLING CODE 4910-13-U
