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Airworthiness Directive packet

AD 2004-10-14

Airworthiness Directives; Lycoming Engines (Formerly Textron Lycoming), Direct-Drive Reciprocating Engines

1 · Quick read — prepared by AircraftDirectives

Our plain-language summary — not the regulation

Requires inspection of the crankshaft gear installation and rework or replacement of the gears where necessary after a propeller strike, sudden stoppage, at overhaul, or whenever gear train repair is required.

AD number
2004-10-14
Federal Register document
04-11406
Citation
69 FR 29210
Amendment
39-13644
Docket
Docket No. 89-ANE-10-AD
Action
Final rule.
Published
2004-05-21
Effective
2004-06-25
Effective (as stated in the rule)
This AD becomes effective June 25, 2004. The Director of the Federal Register approved the incorporation by reference of certain publications listed in the regulations as of June 25, 2004.
Issued by
Transportation Department, Federal Aviation Administration
Regulation
14 CFR 39
Applies to (in our index)
Lycoming O-435

2 · Official Federal Register document — government source, verbatim

Reproduced unedited from the Federal Register
[Federal Register Volume 69, Number 99 (Friday, May 21, 2004)]
[Rules and Regulations]
[Pages 29210-29212]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 04-11406]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 89-ANE-10-AD; Amendment 39-13644; AD 2004-10-14]
RIN 2120-AA64


Airworthiness Directives; Lycoming Engines (Formerly Textron 
Lycoming), Direct-Drive Reciprocating Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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SUMMARY: The FAA is adopting a new airworthiness directive (AD) that 
supersedes an existing AD, for Lycoming Engines (formerly Textron 
Lycoming), direct-drive reciprocating engines (except O-145, O-320H, O-
360E, LO-360E, LTO-360E, O-435, and TIO-541 series engines). That AD 
currently requires inspection of the crankshaft gear installation and 
rework or replacement of the gears where necessary after a propeller 
strike, sudden stoppage, at overhaul, or whenever gear train repair is 
required. This AD requires the same actions but makes the correction 
that the existing gear retaining bolt and lockplate be removed from 
service and new hardware installed, and revises the definitions for 
sudden stoppage and propeller strike. This AD results from a change to 
the definition of a propeller strike or sudden stoppage. We are issuing 
this AD to prevent loosening or failure of the crankshaft gear 
retaining bolt, which may cause sudden engine failure.

DATES: This AD becomes effective June 25, 2004. The Director of the 
Federal Register approved the incorporation by reference of certain 
publications listed in the regulations as of June 25, 2004.

ADDRESSES: You can get the service information identified in this AD 
from Lycoming Engines, 652 Oliver Street, Williamsport, PA 17701, 
U.S.A.; telephone (570) 323-6181; fax (570) 327-7101 or from the 
Lycoming Web site: www.lycoming.textron.com.main.jsp.
    You may examine the AD docket at the FAA, New England Region, 
Office of the Regional Counsel, 12 New England Executive Park, 
Burlington, MA. You may examine the service information at the FAA, New 
England Region, Office of the Regional Counsel, 12 New England 
Executive Park, Burlington, MA; or at the National Archives and Records 
Administration (NARA). For information on the availability of this 
material at NARA, call 202-741-6030, or go to: http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html.

FOR FURTHER INFORMATION CONTACT: Norm Perenson, Aerospace Engineer, New 
York Aircraft Certification Office, FAA, 1600 Stewart Avenue, Suite 
410, Westbury, NY 11590; telephone (516) 228-7337; fax (516) 794-5531.

SUPPLEMENTARY INFORMATION: The FAA proposed to amend 14 CFR Part 39, by 
superseding an AD with a proposed airworthiness directive (AD). The 
proposed AD applies to Lycoming Engines direct-drive reciprocating 
engines (except O-145, O-320H, O-360E, LO-360E, LTO-360E, O-435, and 
TIO-541 series engines). We published the proposed AD in the Federal 
Register on March 25, 2003 (68 FR 14350). That action proposed to 
require inspection of

[[Page 29211]]

the crankshaft gear installation and rework or replacement of the gears 
where necessary after a propeller strike, sudden stoppage, at overhaul, 
or whenever gear train repair is required. That action also proposed to 
revise the definitions for sudden stoppage and propeller strike.

Comments

    We provided the public the opportunity to participate in the 
development of this AD. We have considered the comments received.

Provide a Trigger Level for Action

    One commenter requests that the proposed AD should provide a 
trigger level to alert maintenance personnel of the need for action. 
The commenter states that this is required to avoid having maintenance 
personnel determine the need for action. Also, this would avoid 
miscommunication between the pilot and the maintenance personnel. The 
commenter also states that the proposed AD is too general for proper 
action in the field.
    The FAA does not agree. Section 91.7(b) of the Code of Federal 
Regulations (14 CFR 91.7(b)) states: ``The pilot in command of a civil 
aircraft is responsible for determining whether that aircraft is in 
condition for safe flight.'' The pilot must advise the maintenance 
technician and inspector of the need to perform maintenance. It is also 
the responsibility of the maintenance technician and or inspector to 
advise the pilot when an unsafe condition is found during routine 
maintenance. The actions required by this AD, like many other 
situations in aviation, may require some judgment on the part of the 
pilot, maintenance technician, and or inspector, as well as good 
communication among all parties. Adding additional conditions will only 
require more judgment and more decisions by all parties involved.

AD as Written Will Require Unneeded Inspections

    One commenter states that the proposed AD would require unneeded 
inspections by ``tying the hands'' of knowledgeable mechanics. The 
commenter also states that the final determination regarding needed 
inspections should be made by the maintenance personnel in the field. 
The commenter further states that the mechanics are in the best 
position to evaluate the factors surrounding each incident, and to 
determine which engine components should be inspected.
    The FAA does not agree. The wording in this AD is designed to 
assist the mechanics when deciding on what action to take in a given 
situation. Based on Lycoming's engine design knowledge and worldwide 
service experience, certain situations are known to have caused engine 
problems. This AD is not designed to ``tie the hands of the mechanic''. 
The AD is intended to help the pilot in command and maintenance 
personnel make the best possible maintenance decision.

Correction to the Compliance

    As a correction to the compliance, we added paragraphs to require 
the existing gear retaining bolt and lockplate be removed from service 
and a new bolt and lockplate be installed, and to prohibit installation 
of the removed hardware into any engine. This correction places the AD 
in agreement with the referenced SB.

Conclusion

    We have carefully reviewed the available data, including the 
comments received, and determined that air safety and the public 
interest require adopting the AD with the changes described previously. 
We have determined that these changes will neither increase the 
economic burden on any operator nor increase the scope of the AD. The 
assigned paragraph letters in the regulatory section have been changed 
from what appeared in the proposal, as we are continuing our 
introduction of plain language into our documents.

Regulatory Findings

    We have determined that this AD will not have federalism 
implications under Executive Order 13132. This AD will not have a 
substantial direct effect 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.
    For the reasons discussed above, I certify that this AD:
    (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.
    We prepared a summary of the costs to comply with this AD and 
placed it in the AD Docket. You may get a copy of this summary by 
sending a request to us at the address listed under ADDRESSES. Include 
``AD Docket No. 89-ANE-10-AD'' in your request.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, Safety.

Adoption of the Amendment

0
Accordingly, under the authority delegated to me by the Administrator, 
the Federal Aviation Administration amends 14 CFR part 39 as follows:

PART 39--AIRWORTHINESS DIRECTIVES

0
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]

0
2. The FAA amends Sec.  39.13 by removing Amendment 39-6916 (56 FR 
33205, July 19, 1991), and by adding the following new airworthiness 
directive (AD):

2004-10-14 Lycoming Engines (formerly Textron Lycoming): Amendment 
39-13644. Docket No. 89-ANE-10-AD. Supersedes AD 91-14-22, Amendment 
39-6916.

Effective Date

    (a) This AD becomes effective June 25, 2004.

Affected ADs

    (b) This AD supersedes AD 91-14-22.

Applicability

    (c) This AD applies to Lycoming Engines (formerly Textron 
Lycoming), direct-drive reciprocating engines (except O-145, O-320H, 
O-360E, LO-360E, LTO-360E, O-435, and TIO-541 series engines).

Unsafe Condition

    (d) This AD results from a change to the definition of a 
propeller strike or sudden stoppage. The actions specified in this 
AD are intended to prevent loosening or failure of the crankshaft 
gear retaining bolt, which may cause sudden engine failure.

Compliance

    (e) Compliance with this AD is required as indicated before 
further flight if the engine has experienced a propeller strike as 
defined in paragraphs (i) and (j) of this AD, unless already done.
    (f) Inspect, and if necessary repair, the crankshaft counter 
bored recess, the alignment dowel, the bolt hole threads, and the 
crankshaft gear for wear, galling, corrosion, and fretting in 
accordance with steps 1 through 5 of Lycoming Mandatory Service 
Bulletin (MSB) No. 475C, dated January 30, 2003.
    (g) Remove the existing gear retaining bolt and lockplate from 
service, and install a new bolt and lockplate, in accordance with 
steps 6 and 7 of Lycoming MSB No. 475C, dated January 30, 2003.

[[Page 29212]]

Prohibition of Retaining Bolt and Lockplate

    (h) Do not install the gear retaining bolt and lockplate that 
were removed in paragraph (g) of this AD, into any engine.

Definition of Propeller Strike

    (i) For the purposes of this AD, a propeller strike is defined 
as follows:
    (1) Any incident, whether or not the engine is operating, that 
requires repair to the propeller other than minor dressing of the 
blades.
    (2) Any incident during engine operation in which the propeller 
impacts a solid object that causes a drop in revolutions per minute 
(RPM) and also requires structural repair of the propeller 
(incidents requiring only paint touch-up are not included). This is 
not restricted to propeller strikes against the ground.
    (3) A sudden RPM drop while impacting water, tall grass, or 
similar yielding medium, where propeller damage is not normally 
incurred.
    (j) The preceding definitions include situations where an 
aircraft is stationary and the landing gear collapses causing one or 
more blades to be substantially bent, or where a hanger door (or 
other object) strikes the propeller blade. These cases should be 
handled as sudden stoppages because of potentially severe side 
loading on the crankshaft flange, front bearing, and seal.

Alternative Methods of Compliance

    (k) The Manager, New York Aircraft Certification Office, has the 
authority to approve alternative methods of compliance for this AD 
if requested using the procedures found in 14 CFR 39.19.

Material Incorporated by Reference

    (l) You must use Lycoming MSB No. 475C, dated January 30, 2003, 
to perform the inspections and repairs required by this AD. The 
Director of the Federal Register approved the incorporation by 
reference of this service bulletin in accordance with 5 U.S.C. 
552(a) and 1 CFR part 51. You can get a copy from Lycoming Engines, 
652 Oliver Street, Williamsport, PA 17701, U.S.A; telephone (570) 
323-6181; fax (570) 327-7101. You can review copies at the FAA, New 
England Region, Office of the Regional Counsel, 12 New England 
Executive Park, Burlington, MA; or at the National Archives and 
Records Administration (NARA). For information on the availability 
of this material at NARA, call 202-741-6030, or go to: http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html.

Related Information

    (m) None.

    Issued in Burlington, Massachusetts, on May 12, 2004.
Peter A. White,
Acting Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.
[FR Doc. 04-11406 Filed 5-20-04; 8:45 am]
BILLING CODE 4910-13-P

Sources. Section 1 is written by AircraftDirectives from the record below and is a reading aid only. Section 2 is the United States Government's own text, reproduced without edit.

Federal Register: https://www.federalregister.gov/documents/2004/05/21/04-11406/airworthiness-directives-lycoming-engines-formerly-textron-lycoming-direct-drive-reciprocating

Official PDF: https://www.govinfo.gov/content/pkg/FR-2004-05-21/pdf/04-11406.pdf

Packet generated 2026-08-18 08:52 UTC.

This packet is not an airworthiness determination and not legal or maintenance advice. AircraftDirectives reproduces official records and condenses their wording for easier reading. It does not decide, certify or imply whether any aircraft, engine, appliance or part is airworthy, compliant, affected by this directive, or eligible for return to service. No inspection, approval, or determination of any kind is performed or implied by this document.

Section 1 is a reading aid, not the rule. It is our own plain-language condensation, written to help a reader find the relevant directive quickly. It is NOT a substitute for the regulation, it may omit conditions, exceptions, compliance times, alternative methods of compliance (AMOCs) and applicability limits, and it has no legal force whatsoever. Only the official text governs. Where Section 1 and Section 2 differ in any respect, Section 2 - and the official source it was retrieved from - controls absolutely.

Responsibility remains with the owner/operator. Under 14 CFR §91.403 and §91.417 the owner or operator is responsible for maintaining airworthiness and for required records; under §39.7 no person may operate a product to which an airworthiness directive applies except in accordance with that directive. Determining applicability to a specific serial number and configuration, and performing or supervising any required action, is the responsibility of the owner/operator and appropriately certificated personnel.

Accuracy and currency. Section 2 was retrieved at the time stamped above and is reproduced without edit; Federal Register material is a work of the United States Government. Directives are amended, corrected and superseded over time, and this sheet is a snapshot, not a live record - it does not update after printing. Re-check the official sources before acting on it. This packet is provided without warranty of any kind, express or implied, including fitness for a particular purpose. We do not sell parts and have no commercial interest in any action a directive may require.

AircraftDirectives · AD 2004-10-14 · Section 1 is our plain-language reading aid; Section 2 is the official Federal Register text and controls where the two differ. Not an airworthiness determination — 14 CFR §91.403 / §91.417 responsibility remains with the owner/operator. Retrieved 2026-08-18 08:52 UTC.