[Federal Register Volume 64, Number 27 (Wednesday, February 10, 1999)]
[Rules and Regulations]
[Pages 6516-6518]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-3039]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 98-ANE-81-AD; Amendment 39-11028; AD 99-04-04]
RIN 2120-AA64
Airworthiness Directives; Textron Lycoming Reciprocating Engines
IO-540 and O-540 Engines Equipped With Slick Aircraft Products Magnetos
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 Textron Lycoming IO-540 and O-540 engines equipped
with Slick Aircraft Products magnetos. This action requires removal of
the Slick magneto from the engine and inspection of the impulse
coupling pawl for wear. This amendment is prompted by several service
difficulty reports, two incidents, and an accident involving severely
worn and failed impulse couplings. The actions specified in this AD are
intended to prevent failure of the magneto impulse coupling, resulting
in seizure of the engine.
DATES: Effective February 25, 1999.
The incorporation by reference of certain publications listed in
the regulations is approved by the Director of the Federal Register as
of February 25, 1999.
Comments for inclusion in the Rules Docket must be received on or
before April 12, 1999.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), New England Region, Office of the Regional
Counsel, Attention: Rules Docket No. 98-ANE-81-AD, 12 New England
Executive Park, Burlington, MA 01803-5299. Comments may also be sent
via the Internet using the following address: ``engineprop@faa.gov.'' Comments sent via the Internet must contain the
docket number in the subject line.
The service information referenced in this AD may be obtained from
Textron Lycoming, 652 Oliver Street, Williamsport, PA 17701. This
information may be examined at the FAA, New England Region, Office of
the Regional Counsel, 12 New England Executive Park, Burlington, MA; or
at the Office of the Federal Register, 800 North Capitol Street, NW.,
suite 700, Washington, DC.
FOR FURTHER INFORMATION CONTACT: Rocco Viselli, Aerospace Engineer, New
York Aircraft Certification Office, FAA, Engine & Propeller
Directorate, 10 Fifth Street, 3rd Floor, Valley Stream, NY 11581-1200;
telephone (516) 256-7531, fax (516) 568-2716.
SUPPLEMENTARY INFORMATION: The Federal Aviation Administration (FAA)
has received numerous reports of failure of the impulse coupling pawl
on Slick Aircraft Products magnetos installed on certain Textron
Lycoming IO-540 and O-540 engines that resulted in seizure of the
engine. In one accident, a Piper Cherokee Six airplane equipped with a
Textron Lycoming IO-540 series engine experienced an engine failure.
The left magneto, Slick model number 6531, equipped with impulse
coupling Slick P/N M3333, seized within the housing. The seizure of the
left magneto caused
[[Page 6517]]
the gear drive train to fail. The failure of the gear drive train
caused the right magneto to stop operating, which caused the engine to
stop. In one incident, a magneto seized when one pawl jammed under the
second pawl due to a loose or broken rivet. The seizure resulted in a
forced landing. In another incident, a Piper PA-32 experienced a
reduction in engine power while in cruise flight. Examination of the
engine revealed that the left magneto coupling drive gear had
disintegrated and sheared several drive gear teeth. There have also
been a number of Service Difficulty Reports of severely worn and failed
impulse couplings on certain Textron Lycoming O-540 and IO-540 series
reciprocating engines equipped with Slick Aircraft Products magneto
model numbers 6251, 6252, 6255, 6351 and 6355. Investigation results
suggest that excessive vibration or radial forces acting on the impulse
coupling assembly may be causing unusually rapid wear of the impulse
coupling pawl. In these cases, the impulse coupling may improperly
engage the stop pins when the engine is operating, and cause damage to
the accessory drive gear and impulse coupling. Possible causes of
failed impulse couplings that are currently under investigation include
unusually rapid wear due to excessive vibratory forces, improper
crankcase overhaul in magneto bore location, and lack of routine
magneto inspection and maintenance. This condition, if not corrected,
could result in failure of the magneto impulse coupling, resulting in
seizure of the engine.
The FAA has reviewed and approved the technical contents of Textron
Lycoming Mandatory Service Bulletin (SB) No. 537, dated November 20,
1998. Textron Lycoming SB No. 537 reprints the Slick Aircraft Product
SB SB1-98, dated August 26, 1998, that describes procedures for the
inspection of the impulse coupling pawls for wear and proper operation
and, if necessary, replacement of the impulse coupling assembly.
Since an unsafe condition has been identified that is likely to
exist or develop on certain other Textron Lycoming IO-540 and O-540
engines of the same type design, this AD is being issued to prevent
failure of the magneto impulse coupling, resulting in seizure of the
engine. This AD requires an initial inspection of the magneto impulse
coupling assembly pawls for wear either within the next 10 hours of
time in service (TIS) from the effective date of this AD if the magneto
has been in service for more than 250 hours TIS since new or overhauled
or if the service history of the magneto is unknown, or within the next
10 hours of TIS from the effective date of this AD or by 250 hours TIS
since new or overhauled whichever is later if the magneto has been in
service for less than 250 hours TIS since new or overhauled; and then
repetitive inspections every 250 hours TIS from the last inspection or
overhaul of the magneto. The actions are required to be accomplished in
accordance with the SB described previously. A final, terminating
action cannot be defined until the investigation is completed.
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 should 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 notice must submit a self-addressed,
stamped postcard on which the following statement is made: ``Comments
to Docket Number 98-ANE-81-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 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. 106(g), 40113, 44701.
Sec. 39.13 [Amended]
2. Section 39.13 is amended by adding the following new
airworthiness directive:
99-04-04 Textron Lycoming: Amendment 39-11028. Docket 98-ANE-81-AD.
Applicability: Textron Lycoming O-540-B2B5, B2C5, E4B5, E4C5,
G1A5, G2A5, IO-540-K1A5, K1B5, and K1G5 reciprocating model engines
equipped with Slick Aircraft Products magneto model numbers 6251,
6252, 6255, 6351 and 6355. These engines are installed on, but not
limited to, the following airplanes: Britten Norman BN-2A, -2A-2, -
2A-3, -2A-6, -2A-9, -2A-20, -2A-21, -2A-26, -2A-27, -2A-MKIII, -2A-
MKIII-2, -2A-MKIII-3, -2B-20, -2B-21, -2B-26,
[[Page 6518]]
-2B-27 and Piper PA-25-235, PA-25-260, PA-32-260, PA-32-300.
Note 1: This airworthiness directive (AD) applies to each engine
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 engines 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 failure of the magneto impulse coupling, resulting in
seizure of the engine, accomplish the following:
(a) For engines on which the service history of the magneto is
not known, or on which the magneto has greater than 250 hours TIS
since new, factory rebuilt, or overhauled, on the effective date of
this AD, within 10 hours of the effective date of this AD, inspect
the components of the magneto impulse coupling for the conditions
listed in accordance with steps 1 through 7 of the Textron Lycoming
Mandatory SB No. 537, dated November 20, 1998.
Note 2: The Textron Lycoming Mandatory SB No. 537 dated November
20, 1998 contains the Slick SB No. SB1-98 dated August 26, 1998 in
its entirety. The steps referenced to the Textron Lycoming SB No.
537 dated November 20, 1998 by this compliance section are the same
steps that are contained in the Slick SB No. SB1-98 dated August 26,
1998.
(b) For engines on which the magneto has less than or equal to
250 hours TIS since new, factory rebuilt, overhauled on the
effective date of this AD, before accumulating 250 hours TIS since
new, factory rebuilt or overhauled, or within 10 hours TIS from the
effective date of this AD, whichever comes later, inspect the
components of the magneto impulse coupling for the conditions listed
in accordance with steps 1 through 7 of the Textron Lycoming
Mandatory SB No. 537, dated November 20, 1998.
(c) Thereafter, at intervals not to exceed 250 hours TIS since
the last inspection performed in accordance with this AD, inspect
the components of the magneto impulse coupling for the conditions
listed in accordance steps 1 through 7 of the Textron Lycoming
Mandatory SB No. 537, dated November 20, 1998.
(d) Remove magneto impulse coupling before 2,000 hours TIS since
new and replace with a serviceable part.
(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, New York Aircraft Certification
Office. Operators shall submit their requests through an appropriate
FAA Principal Maintenance Inspector, who may add comments and then
send it to the Manager, New York Aircraft Certification Office.
Note 3: Information concerning the existence of approved
alternative methods of compliance with this airworthiness directive,
if any, may be obtained from the New York Aircraft Certification
Office.
(f) The inspection shall be done in accordance with the
following Textron Lycoming Mandatory SB:
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Document No. Pages Revision Date
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SB No. 537.......................... 1-9.................. Original.............. Nov. 20, 1998.
Total pages: 9......................
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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 Textron Lycoming, 652 Oliver Street,
Williamsport, PA 17701. Copies may be inspected at the FAA, New England
Region, Office of the Regional Counsel, 12 New England Executive Park,
Burlington, MA; or at the Office of the Federal Register, 800 North
Capitol Street, NW., suite 700, Washington, DC.
(g) This amendment becomes effective on February 25, 1999.
Issued in Burlington, Massachusetts, on February 1, 1999.
David A. Downey,
Assistant Manager, Engine and Propeller Directorate, Aircraft
Certification Service.
[FR Doc. 99-3039 Filed 2-9-99; 8:45 am]
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