[Federal Register Volume 60, Number 2 (Wednesday, January 4, 1995)]
[Proposed Rules]
[Pages 389-393]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 95-62]
[[Page 389]]
DEPARTMENT OF TRANSPORTATION
14 CFR Part 39
[Docket No. 94-NM-114-AD]
Airworthiness Directives; McDonnell Douglas Model DC-10 Series
Airplanes and Model KC-10A (Military) Airplanes
AGENCY: Federal Aviation Administration, DOT.
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 certain McDonnell Douglas Model
DC-10 series airplanes and Model KC-10A (military) airplanes. This
proposal would require various modifications of the flight controls,
hydraulic power systems, and landing gear. This proposal is prompted by
a recommendation by the Systems Review Task Force (SRTF) for
accomplishment of certain modifications that will enhance the
controllability of these airplanes in the unlikely event of
catastrophic damage to all hydraulics systems. The actions specified by
the proposed AD are intended to ensure airplane survivability in the
event of damage to fully powered flight control systems.
DATES: Comments must be received by March 1, 1995.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), Transport Airplane Directorate, ANM-103,
Attention: Rules Docket No. 94-NM-114-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 McDonnell Douglas Corporation, P.O. Box 1771, Long Beach,
California 90801-1771, Attention: Business Unit Manager, Technical
Administrative Support, Dept. L51, Mail Code 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, 3960 Paramount
Boulevard, Lakewood, California.
FOR FURTHER INFORMATION CONTACT: Mauricio J. Kuttler, Aerospace
Engineer, Systems and Equipment Branch, ANM-131L, FAA, Transport
Airplane Directorate, Los Angeles Aircraft Certification Office, 3960
Paramount Boulevard, Lakewood, California 90712; telephone (310) 627-
5355; fax (310) 627-5210.
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 94-NM-114-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. 94-NM-114-AD, 1601 Lind Avenue, SW., Renton, Washington
98055-4056.
Discussion-
In July 1989, a McDonnell Douglas Model DC-10-30 series airplane
was involved in an accident in Sioux City, Iowa, resulting in the
deaths of 110 passengers and one crewmember. The National
Transportation Safety Board (NTSB) identified the catastrophic
disintegration of the stage 1 fan disk of one of the engines as a
probable cause of the accident. The resulting debris damaged the
hydraulic systems that power the flight controls, resulting in the loss
of virtually all control capability.-
Following the accident, the Administrator of the Federal Aviation
Administration convened a Systems Review Task Force (SRTF) to
investigate means for enhancing airplane survivability following damage
to fully powered flight control systems. The SRTF formed working groups
to perform these investigations for specific airplane models to
determine what actions could be effective in protecting other transport
category airplanes with powered flight control systems from similar
engine or systems failures.-
The SRTF working group assigned to review Model DC-10 series
airplanes completed its review of the Model DC-10 design, including
existing service bulletins, and issued a report recommending
accomplishment of certain modifications described in 12 Model DC-10
service bulletins. A copy of the report is contained in the Rules
Docket for this AD action.
Explanation of Relevant Service Documents-
The FAA has reviewed and approved the 12 McDonnell Douglas DC-10
Service Bulletins recommended for accomplishment by the SRTF working
group. Accomplishment of the modifications specified in these service
bulletins will enhance the controllability of the airplane in the
unlikely event of catastrophic damage to all three hydraulic systems in
the tail area of the airplane.
Seven of the 12 service bulletins discussed previously describe
procedures for various modifications of the flight controls:-
1. McDonnell Douglas DC-10 Service Bulletin 27-71, Revision 1,
dated February 14, 1973, was issued in response to reports of failures
of the piping of the hydraulic system of the horizontal stabilizer on
Model DC-10 series airplanes that had accumulated as few as 70 flight
hours. The failures were attributed to rapid release of the trim
control handles of the stabilizer, which resulted in pressure surges
that were abnormally high in the hydraulic system of the stabilizer.
Continued high pressure surges and externally induced vibrations could
result in fatigue failure of the hydraulic piping. These conditions, if
not corrected, could result in the loss of fluid, which could render
the affected system inoperative.-
The service bulletin describes procedures for installation of surge
damper assemblies and new piping assemblies in hydraulic systems 1 and
3 of the horizontal stabilizer. Installation of the dampers and piping
will ensure that high pressure surges are absorbed and will prevent
pipe failures.-
2. McDonnell Douglas DC-10 Service Bulletin 27-120, dated February
10, 1975, describes procedures for modification and reidentification of
the trim hydraulic motor assembly of the [[Page 390]] horizontal
stabilizer. Accomplishment of the modification will minimize the
possibility of fatigue failure of the motor case screws and shuttle
valve screws. (The service bulletin references Sperry Rand Corporation,
Vickers Division, Service Bulletin 390017-27-2, dated December 2, 1974,
as an additional source of service information.) Failure of the motor
case screws and/or failure of the shuttle valve screws, if not
corrected, could result in loss of hydraulic system fluid. Failure of
two shuttle valve screws could cause the shuttle valve to separate from
the trim motor.-
3. McDonnell Douglas DC-10 Service Bulletin 27-152, dated August 9,
1976, was issued in response to a report of inoperative horizontal
stabilizer trim due to disengagement of the torsional coupling of the
drive system on Model DC-10 series airplanes that had accumulated
approximately 4,100 flight hours. In addition, during fleet
inspections, loose retaining nuts and locking clips were found on these
airplanes; the torsional nut did not engage adequately to provide
locking action. The inoperative horizontal stabilizer trim was
attributed to failure of the locking clip to prevent the retaining nut
of the torsional coupling from rotating and becoming loose. This
condition could result in the retaining nut becoming loose and allowing
disengagement of the torsional coupling. This condition, if not
corrected, could result in the loss of horizontal stabilizer trim
capability.
The service bulletin describes procedures for replacing the
existing locking clip on the torsional coupling of the horizontal
stabilizer with a new nut retainer of an improved design.
Accomplishment of this modification will minimize the possibility of
the torsional nut becoming loose.-
4. McDonnell Douglas DC-10 Service Bulletin 27-181, Revision 1,
dated May 28, 1981, was issued in response to reports of failure of the
differential drive shear pin in the horizontal stabilizer drive system.
These failures occurred during takeoff climb on Model DC-10 series
airplanes that had accumulated between 4 and 4,201 flight hours.
Investigation revealed that these failures were caused by bending
fatigue of the shear pin due to a loose fit. Failure of the shear pin
could result in an inoperative horizontal stabilizer drive system. This
condition, if not corrected, could result in reduced controllability of
the airplane.-
The service bulletin describes procedures for installation of a
modified chain drive unit on the horizontal stabilizer. The new unit
incorporates a larger shear pin with a single shear point having a
larger diameter with less constraint. Accomplishment of this
modification will increase the reliability of the drive assembly.-
5. McDonnell Douglas DC-10 Service Bulletin 27-201, dated December
30, 1985, was issued in response to a report of in-flight loss of
hydraulic systems 1 and 2 shortly after takeoff of a Model DC-10 series
airplane. Investigation revealed that the loss of hydraulic systems was
caused by blowout of the number 6 tire after gear retraction. The
blowout deflected the keel web structure, which ruptured hydraulic
pipes to the flap lock valves and caused rapid loss of fluid. This
condition, if not corrected, could result in loss of operation of the
hydraulic system.-
The service bulletin describes procedures for replacement of the
hydraulic pipe assemblies of the flap lock valve with new pipe
assemblies having increased flexibility and strength. Installation of
these pipe assemblies will minimize the possibility of rupture of the
pipe assemblies during events such as those described previously.-
6. McDonnell Douglas DC-10 Service Bulletin 27-208, dated September
5, 1989, was issued in response to reports of cracking of the end caps
of the trim control valve of the horizontal stabilizer on Model DC-10
series airplanes that had accumulated between 9,800 and 16,000 flight
hours. Investigation revealed that fatigue cracking initiated from
inside the radius of the end cap. Such fatigue cracking, if not
corrected, could result in loss of hydraulic fluid and eventual
shutdown of the hydraulic system.-
The service bulletin describes procedures for replacement of eight
end caps of the trim control valve of the horizontal stabilizer with
new end caps having a larger inside radius. Replacement of the end caps
will minimize the possibility of cracking of the end caps.-
7. McDonnell Douglas DC-10 Service Bulletin 27-209, dated October
20, 1989, was issued in response to reports of failure of the chain
drive fuse of the horizontal stabilizer on Model DC-10 series airplanes
that had accumulated between 4,000 and 18,000 flight hours.
Investigation revealed that a fuse pin within the chain drive unit had
sheared due to loose nuts on the shaft assembly. These conditions, if
not corrected, could result in the horizontal stabilizer drive system
becoming inoperative.-
The service bulletin describes procedures for inspecting the nuts
on the shaft assembly for looseness, proper orientation, excess
backlash, and engagement of the washer locking tab; and replacing the
fuse pin, adjusting backlash, and properly positioning and tightening
the nuts, if necessary. Replacing the fuse pin and tightening the nuts
will minimize the possibility of failure of the chain drive fuse of the
horizontal stabilizer.-
Two of the 12 service bulletins describe procedures for
modifications of certain hydraulic power systems:-
8. McDonnell Douglas DC-10 Service Bulletin 29-109, Revision 1,
dated September 22, 1978, was issued in response to reports of rapid
rise in temperature in hydraulic system 3 subsequent to the loss of
hydraulic fluid in hydraulic system 1 or 2. Investigation revealed that
a shutoff valve on the reversible motor pump may fail on one side of
the reversible motor pump and that failure may go undetected. This
failure poses a problem if a failure occurs in the opposite hydraulic
system that causes total loss of that system's fluid. If a valve fails
in the open position on one side and fluid is lost from the opposite
hydraulic system, the reversible motor pump will rotate at maximum rpm
(limited by the flow control). This condition, if not corrected, could
result in a rise in temperature in the opposite hydraulic system, which
may necessitate limited use of the engine-drive pumps on that hydraulic
system.-
The service bulletin describes procedures for installation of an
indication system that will allow the flight crew to immediately detect
an inoperative shutoff valve on the reversible motor pump. The
installation of the indication system involves installing two pressure
switches on the reversible motor pumps; installing a ground stud, two
relays, and receptacles on the center compartment electrical rack;
replacing the 6-post terminal strip in the wheel well of the right main
landing gear with an 8-post terminal strip; installing an annunciator
legend on the flight engineer's annunciator panel; installing a circuit
breaker and replacing the nameplate on the flight engineer's circuit
breaker panel; revising the failure indication wiring on the constant
speed drive; and installing indication wiring and associated clamps and
brackets on the reversible motor pump.-
9. McDonnell Douglas DC-10 Service Bulletin 29-125, Revision 2,
dated October 23, 1987, was issued in response to reports of complete
loss of fluid from the number 3 hydraulic system. The fluid loss was
caused by a ruptured hi-pressure switch on the hydraulic case drain.
This condition, if [[Page 391]] not corrected, could result in the loss
of function of the hydraulic system.
The service bulletin describes procedures for modification of the
main hydraulic power system. The modification involves replacing the
hi-pressure switches on the hydraulic case drain on engine numbers 1,
2, and 3 with plugs; removing one relay and one receptacle on the aft
relay panel of the equipment rack; replacing the existing legend in
position 8 on the flight engineer's annunciator panel with a blank
legend; and revising the wiring for indicating the aircraft hydraulic
temperature and pressure. Accomplishment of this modification will
minimize the possibility of loss of hydraulic fluid.-
Three of the 12 service bulletins describe procedures for
modifications of the landing gear:-
10. McDonnell Douglas DC-10 Service Bulletin 32-134, dated March
22, 1977, was issued in response to reports of damage to the electrical
and hydraulic installations of the aft antiskid manifold on the main
landing gear. The damage resulted from blown tire fragments and debris,
which rendered the antiskid system inoperative and, in one case,
ruptured a hydraulic pipe. Failure of the pipe, if not corrected, could
cause hydraulic system numbers 1 or 3 to become inoperative due to the
loss of hydraulic fluid.-
The service bulletin describes procedures for modification of the
aft antiskid manifold on the left and right main landing gear. The
modification entails installing a protective shield and associated
brackets on the aft antiskid manifold. Accomplishment of this
modification will minimize the possibility of damage to the aft
antiskid manifold.-
11. McDonnell Douglas DC-10 Service Bulletin 32-143, dated August
8, 1978, was issued in response to reports of damage to the brake
piping that is routed between the antiskid manifolds and the swivel
glands of the main landing gear. This damage occurred as a result of
the impact of debris following failure of a tire on the main landing
gear. A ruptured antiskid return pipe could result in loss of fluid
from the affected antiskid system during application of the brakes. A
single failure of a pressure pipe will limit brake performance on a
single system. Failure of brake pressure pipes in both systems, if not
corrected, could result in complete loss of braking capability.-
The service bulletin describes procedures for installation of
protective shields over the brake and the antiskid piping located on
the aft side of the left and right main landing gear. Accomplishment of
this modification will minimize the possibility of brake pressure and
damage to the antiskid return piping caused by failure of a tire on the
main landing gear.-
12. McDonnell Douglas DC-10 Service Bulletin 32-157, Revision 1,
dated October 29, 1980, was issued in response to a report of damage to
a support bracket on the aileron trim cable and to a flight control
mixer in the wheel well of the centerline landing gear. Investigation
revealed that the damage was caused by the impact of a tire tread that
was thrown into the open area created by the aft doors on the
centerline landing gear when the landing gear is in the down position.
This condition, if not corrected, could result in damage to components
located in the wheel well of that landing gear.-
The service bulletin describes procedures for installing a doubler
on the web assembly between the wheel wells of the center landing gear
and the right main landing gear; installing a fiberglass deflector
assembly on the shock strut of the centerline landing gear; replacing
the pressure gage manifold of the shock strut; and installing an
instruction plate and adding precaution instruction markings in the
wheel well of the right main landing gear and on the forward door of
the center landing gear. Accomplishment of this modification will
minimize the possibility of damage to components in the wheel well of
the centerline landing gear caused by a thrown tire tread or other
debris.
Explanation of the 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 various modifications of the flight controls,
hydraulic power systems, and landing gear. The actions would be
required to be accomplished in accordance with the McDonnell Douglas
service bulletins described previously.-
The FAA is continuing to review the recommendations of the SRTF
working group for these airplanes and may consider further rulemaking
based on those recommendations.-
As a result of recent communications with the Air Transport
Association (ATA) of America, the FAA has learned that, in general,
some operators may misunderstand the legal effect of AD's on airplanes
that are identified in the applicability provision of the AD, but that
have been altered or repaired in the area addressed by the AD. The FAA
points out that all airplanes identified in the applicability provision
of an AD are legally subject to the AD. If an airplane has been altered
or repaired in the affected area in such a way as to affect compliance
with the AD, the owner or operator is required to obtain FAA approval
for an alternative method of compliance with the AD, in accordance with
the paragraph of each AD that provides for such approvals. A note has
been included in this notice to clarify this requirement.
Cost Impact-
There are approximately 427 Model DC-10 series airplanes and Model
KC-10A (military) airplanes of the affected design in the worldwide
fleet. The FAA estimates that 254 airplanes of U.S. registry would be
affected by this proposed AD.-
Approximate work hours to accomplish the proposed actions and costs
for required parts are listed in the following table. The average labor
rate is $60 per work hour.
------------------------------------------------------------------------
Estimated Parts cost Total cost
Service bulletin No.- work per per
hours- airplane airplane
------------------------------------------------------------------------
27-71................................ 5 (\1\) $300.00
27-120............................... 3 $68.00 248.00
27-152............................... 1 278.00 338.00
27-181............................... 5 431.00 731.00
27-201............................... 10 7,943.00 8,543.00
27-208............................... 5 3,704.00 4,004.00
27-209............................... 9 N/A 540.00
29-109............................... 101 713.00 6,773.00
29-125............................... 4 498.00 738.00
32-134............................... 3 2,034.00 2,214.00
32-143............................... 3 649.00 829.00
32-157............................... 6 46,463.00 46,823.00
------------------------------------------------------------------------
\1\Required parts would be supplied by the manufacturer at no cost to
operators.-
Based on these figures, the total cost impact of the proposed AD on
U.S. operators is estimated to be $18,308,574, or $72,081 per
airplane.-
The total cost impact figure discussed above is 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.-
The number of required work hours, as indicated above, is presented
as if the accomplishment of the actions proposed in this AD were to be
conducted as ``stand alone'' actions. However, the 24-month compliance
time specified in paragraph (a) of this proposed AD should allow ample
time for the actions to be accomplished coincidentally with scheduled
major airplane inspection and maintenance activities, thereby
minimizing the costs associated with special airplane scheduling.-
[[Page 392]]
Further, the FAA recognizes that the obligation to maintain
aircraft in an airworthy condition is vital, but sometimes expensive.
Because AD's require specific actions to address specific unsafe
conditions, they appear to impose costs that would not otherwise be
borne by operators. However, because of the general obligation of
operators to maintain aircraft in an airworthy condition, this
appearance is deceptive. Attributing those costs solely to the issuance
of this AD is unrealistic because, in the interest of maintaining safe
aircraft, most prudent operators would accomplish the required actions
even if they were not required to do so by the AD. -
A full cost-benefit analysis has not been accomplished for this
proposed AD. As a matter of law, in order to be airworthy, an aircraft
must conform to its type design and be in a condition for safe
operation. The type design is approved only after the FAA makes a
determination that it complies with all applicable airworthiness
requirements. In adopting and maintaining those requirements, the FAA
has already made the determination that they establish a level of
safety that is cost-beneficial. When the FAA, as in this proposed AD,
makes a finding of an unsafe condition, this means that the original
cost-beneficial level of safety is no longer being achieved and that
the proposed actions are necessary to restore that level of safety.
Because this level of safety has already been determined to be cost-
beneficial, a full cost-benefit analysis for this proposed AD would be
redundant and unnecessary.
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. 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 adding the following new
airworthiness directive:
McDonnell Douglas: Docket 94-NM-114-AD.-
Applicability: Model DC-10-10, -10F, -15, -30, -30F, -40, and -
40F series airplanes and Model KC-10A (military) airplanes; as
listed in the following McDonnell Douglas DC-10 service bulletins;
certificated in any category:-
------------------------------------------------------------------------
Service bulletin No. - Revision level - Date issued-
------------------------------------------------------------------------
27-71-................. 1 -.................... February 14, 1973.-
27-120-................ Original-.............. February 10, 1975.-
27-152-................ Original-.............. August 9, 1976.-
27-181-................ 1 -.................... May 28, 1981.-
27-201-................ Original-.............. December 30, 1985.-
27-208-................ Original-.............. September 5, 1989.-
27-209-................ Original-.............. October 20, 1989.-
29-109-................ 1-..................... September 22, 1978.-
29-125-................ 2-..................... October 23, 1987.-
32-134-................ Original-.............. March 22, 1977.-
32-143-................ Original-.............. August 8, 1978.-
32-157-................ 1-..................... October 29, 1980.-
------------------------------------------------------------------------
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 (b) 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 ensure airplane survivability in the event of damage to fully
powered flight control systems, accomplish the following:-
(a) Within 24 months after the effective date of this AD, modify
the flight controls, hydraulic power systems, and landing gear in
accordance with paragraphs (a)(1) through (a)(12) of this AD, as
applicable.-
(1) For airplanes listed in McDonnell Douglas DC-10 Service
Bulletin 27-71, Revision 1, dated February 14, 1973: Install surge
damper assemblies and new piping assemblies in hydraulic systems 1
and 3 of the horizontal stabilizer in accordance with the service
bulletin. As of the effective date of this AD, no person shall
install a pipe assembly, part number AJK7004-641, -642, -643, -644,
-645, -646, -647, or -648 on any airplane. As of the effective date
of this AD, no person shall install a valve assembly, part number
AJG7041-5515 or -5517, on any airplane unless that assembly has been
modified in accordance with the service bulletin.-
(2) For airplanes listed in McDonnell Douglas DC-10 Service
Bulletin 27-120, dated February 10, 1975: Modify and reidentify the
trim hydraulic motor assembly of the horizontal stabilizer in
accordance with the service bulletin.
Note 2: The McDonnell Douglas service bulletin references Sperry
Rand Corporation, Vickers Division, Service Bulletin 390017-27-2,
dated December 2, 1974, as an additional source of service
information.
(3) For airplanes listed in McDonnell Douglas DC-10 Service
Bulletin 27-152, dated August 9, 1976: Replace the existing
retaining nut locking clip on the torsional coupling of the
horizontal stabilizer with a new retaining nut locking clip in
accordance with the service bulletin. As of the effective date of
this AD, no person shall install a locking clip or nut retainer,
part number AJH7259-1, on any airplane.-
(4) For airplanes listed in McDonnell Douglas DC-10 Service
Bulletin 27-181, Revision 1, dated May 28, 1981: Install a modified
chain drive unit on the horizontal stabilizer in accordance with the
service bulletin. As of the effective date of this AD, no person
shall install a chain drive unit assembly, part number AJH7337-1 or
AJH7337-501; pin, part number AJH7343-1; housing assembly, part
number AJH7345-1; shaft, part number AJH7075-1 or -501; or decal,
part number AJH7347-1; on any airplane.-
(5) For airplanes listed in McDonnell Douglas DC-10 Service
Bulletin 27-201, dated December 30, 1985: Replace the hydraulic pipe
assemblies of the flap lock valve with new pipe assemblies in
accordance with the service bulletin. As of the effective date of
this AD, no person shall install a pipe assembly, part number
AYK7002-876, -877, -878, -879, -880, and -881; AYK7136-1; and
AYK7137-1; on any airplane.- [[Page 393]]
(6) For airplanes listed in McDonnell Douglas DC-10 Service
Bulletin 27-208, dated September 5, 1989: Replace eight end caps of
the trim control valve of the horizontal stabilizer with new end
caps having a larger inside radius, in accordance with the service
bulletin. As of the effective date of this AD, no person shall
install an end cap, part number AJG7020-503; or valve assembly, part
number AJG7041-5535, -5533, -5531, -5529, -5527, -5525, -5523, -
5521, -5519, -5517, -5515, -5513, -5511, -5509, -5507, -5505, -5503,
-5501, or -5001; on any airplane.-
(7) For airplanes listed in McDonnell Douglas DC-10 Service
Bulletin 27-209, dated October 20, 1989: Inspect the nuts on the
shaft assembly for looseness, proper orientation, excess backlash,
and engagement of the washer locking tab, in accordance with the
service bulletin. As of the effective date of this AD, no person
shall install a drive assembly, part number AJH7337-505, on any
airplane unless that assembly has been modified in accordance with
the service bulletin.-
(i) If no discrepancy is found, no further action is required by
this paragraph.-
(ii) If any discrepancy is found, prior to further flight,
replace the fuse pin, adjust backlash, and properly position and
tighten the nuts in accordance with the service bulletin.-
(8) For airplanes listed in McDonnell Douglas Service Bulletin
29-109, Revision 1, dated September 22, 1978: Install an indication
system on the reversible motor pump in accordance with the service
bulletin. As of the effective date of this AD, no person shall
install a nameplate, part number ABN7191-1124, -1125, -1126, -872, -
873, -874, -878, or -1084; a support, part number 2394536-509; or a
plate, part number 2710497-1-6; on any airplane.-
(9) For airplanes listed in McDonnell Douglas DC-10 Service
Bulletin 29-125, Revision 2, dated October 23, 1987: Modify the main
hydraulic power system in accordance with the service bulletin. As
of the effective date of this AD, no person shall install an
annunciator panel, part number 102200-268, or -274, on any airplane
unless that panel has been modified in accordance with the service
bulletin.-
(10) For airplanes listed in McDonnell Douglas DC-10 Service
Bulletin 32-134, dated March 22, 1977: Modify the aft antiskid
manifold on the left and right main landing gear in accordance with
the service bulletin. As of the effective date of this AD, no person
shall install a bracket, part number ARG7291-1, ARG7291-501,ARG7485-
501, or ARG7485-502 on any airplane. As of the effective date of
this AD, no person shall install a main landing gear assembly, part
number ARG7393-(Any Configuration), on any airplane unless that
assembly has been modified in accordance with the service bulletin.-
(11) For airplanes listed in McDonnell Douglas DC-10 Service
Bulletin 32-143, dated August 8, 1978: Install protective shields
over the brake and antiskid piping located on the aft side of the
left and right main landing gear in accordance with the service
bulletin. As of the effective date of this AD, no person shall
install a support, part number ARG7551-1 or ARG7552-1, or bracket,
part number AEP8009-25, on any airplane. As of the effective date of
this AD, no person shall install a main landing gear assembly, part
number ARG7393-(Any Configuration), on any airplane unless that
assembly has been modified in accordance with the service bulletin.-
(12) For airplanes listed in McDonnell Douglas DC-10 Service
Bulletin 32-157, Revision 1, dated October 29, 1980: Install a
doubler on the web assembly between the wheel wells of the center
landing gear and the right main landing gear; install a fiberglass
deflector assembly on the shock strut of the centerline landing
gear; replace the pressure gage manifold of the shock strut; and
install an instruction plate and adding precaution instruction
markings in the wheel well of the right main landing gear and on the
forward door of the center landing gear in accordance with the
service bulletin. As of the effective date of this AD, no person
shall install a manifold, part number AYK7162-501, on any airplane.-
(b) 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 Aircraft Certification
Office (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 3: Information concerning the existence of approved
alternative methods of compliance with this AD, if any, may be
obtained from the Los Angeles ACO.
(c) 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 28, 1994.
S.R. Miller,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 95-62 Filed 1-3-95; 8:45 am]
BILLING CODE 4910-13-U