Published 1999-02-03 · Federal Register document 99-2474
Airworthiness Directives; Textron Lycoming Model O-540-F1B5 Reciprocating Engines
Publication summary
This amendment adopts a new airworthiness directive (AD) that is applicable to Textron Lycoming Model O-540-F1B5 reciprocating engines. This action requires the removal and replacement of the crankshaft gear retaining bolts. This amendment is prompted by 2 reported failures of the crankshaft gear retaining bolts. The actions specified in this AD are intended to prevent failure of the crankshaft gear retaining bolts, which can result in engine failure and subsequent autorotation and forced landing.
Why this record is shown
Source: Federal Register annual FAA metadata. Acquired 2026-09-03T22:22:57.343810+00:00. The title, summary and date are source facts.
- Source revision
- federal_register_ad_metadata_1999-e9a7378e7e7d30d5
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- results[52]
- Raw source SHA-256
- e9a7378e7e7d30d51578560dc0677c56bb1fef0a9323224e2a0afe1544919217
Final-rule publication
Recorded publication clauses
- AD identifier printed in this edition
- 99-03-05
- Effective date printed in this edition
- 1999-02-18
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Read 2 complete recorded clauses
Applicability wording · Applicability
Applicability: Textron Lycoming Model O-540-F1B5 reciprocating
engines, with the following Textron Lycoming Engine Serial Numbers,
installed on but not limited to Robinson Helicopters Co. Model R-44
rotorcraft.
L-24545-40A L-24628-40A
L-24766-40A L-24772-40A
L-25050-40A L-25052-40A
L-25053-40A L-25054-40A
L-25063-40A L-25064-40A
L-25065-40A L-25066-40A
L-25067-40A L-25068-40A
L-25069-40A L-25070-40A
L-25071-40A L-25072-40A
L-25073-40A L-25074-40A
L-25075-40A L-25076-40A
L-25077-40A L-25078-40A
L-25080-40A L-25081-40A
L-25083-40A L-25084-40A
L-25085-40A L-25086-40A
L-25087-40A L-25088-40A
L-25089-40A L-25090-40A
L-25091-40A L-25092-40A
L-25093-40A L-25094-40A
L-25095-40A L-25096-40A
L-25097-40A L-25098-40A
L-25099-40A L-25100-40A
L-25101-40A L-25102-40A
L-25103-40A L-25104-40A
L-25105-40A L-25106-40A
L-25116-40A L-25117-40A
L-25118-40A L-25119-40A
L-25120-40A L-25121-40A
L-25122-40A L-25123-40A
L-25124-40A L-25125-40A
L-25126-40A L-25127-40A
L-25128-40A L-25129-40A
L-25130-40A L-25131-40A
L-25132-40A L-25133-40A
L-25134-40A L-25135-40A
L-25136-40A L-25137-40A
L-25138-40A L-25139-40A
L-25140-40A L-25141-40A
L-25142-40A L-25143-40A
L-25144-40A L-25145-40A
L-25146-40A L-25149-40A
L-25150-40A L-25154-40A
L-25155-40A L-25156-40A
L-25157-40A L-25158-40A
L-25159-40A L-25160-40A
L-25161-40A L-25162-40A
L-25164-40A L-25166-40A
L-25167-40A L-25168-40A
L-25169-40A L-25170-40A
L-25171-40A L-25172-40A
L-25173-40A L-25174-40A
L-25175-40A L-25176-40A
L-25177-40A L-25178-40A
L-25179-40A L-25180-40A
L-25181-40A L-25182-40A
L-25183-40A L-25184-40A
L-25185-40A L-25186-40A
L-25188-40A L-25189-40A
L-25190-40A L-25191-40A
L-25192-40A L-25193-40A
L-25198-40A L-25200-40A
L-25201-40A L-25202-40A
L-25204-40A L-25206-40A
L-25207-40A L-25208-40A
L-25211-40A L-25212-40A
L-25213-40A L-25214-40A
L-25216-40A L-25217-40A
L-25218-40A L-25219-40A
L-25221-40A L-25222-40A
L-25223-40A L-25228-40A
L-25229-40A L-25230-40A
L-25231-40A L-25232-40A
L-25233-40A L-25234-40A
L-25235-40A L-25236-40A
L-25237-40A L-25238-40A
L-25239-40A L-25240-40A
L-25242-40A L-25243-40A
L-25244-40A L-25246-40A
L-25249-40A L-25250-40A
L-25251-40A L-25252-40A
L-25257-40A
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 (b) 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.
Exact source excerpt. Text positions 8892–12373, end exclusive, in the original decoded publication. SHA-256: 5326d25e79e180e73449aef06865fbf5fcf05a12a7dbd807310210dd6a8bd002
Compliance and requirements
Compliance: Required as indicated, unless accomplished
previously.
To prevent failure of the crankshaft gear retaining bolts, which
can result in engine failure and subsequent autorotation and forced
landing, accomplish the following:
(a) Within 10 hours time in service, or 3 days after the
effective date of this AD, whichever occurs first, have the
crankshaft gear retaining bolt, part number STD-2209, replaced by
Textron Lycoming or Robinson Helicopter Company.
(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, 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 2: 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.
(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 aircraft to a location where
the requirements of this AD can be accomplished.
(d) This amendment becomes effective on February 18, 1999.
Exact source excerpt. Text positions 12373–13781, end exclusive, in the original decoded publication. SHA-256: 65e4613d6585dba7a25f0b335bdf9e45a8aa5fcca2021368b9d1083861802df1
No replacement link has been established from this edition. The complete historical rule chain and current legal effect remain unknown.
Find all recorded historical references to AD 99-03-05 · 0 printed reference observations in this pinned collection.
These are observations from one dated publication. Current legal status is unknown; aircraft applicability, installed configuration, compliance and burden require separate evidence. Missing or unparsed conditions remain unknown.
Why these observations are shown
They were extracted offline from the same immutable official HTML source as the complete recorded text. The dated source wording, original text coordinates and exact quote digests are retained. PDF/text agreement and current regulatory effect have not been qualified.
Observation revision: whole-ad-publication-clause-observations-1.0.1. Text SHA-256: a2412eabe8b0333c3efb1755169098d5e1f80aa0b3fa6a1fc2eaacd5fa88a6a2. Source manifest: 87e26990eb8e26eee4c66664079b6955756bf605a96a8ae690a4c04bf8ba2f9d.
Official source · 1999-02-03
Publication text
This is the complete recorded text of this dated publication.
Current legal effect is unknown. Aircraft applicability, installed configuration and compliance require separate evidence. PDF/text agreement has not been evaluated.
Read the complete official publication text
[Federal Register Volume 64, Number 22 (Wednesday, February 3, 1999)]
[Rules and Regulations]
[Pages 5149-5150]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-2474]
========================================================================
Rules and Regulations
Federal Register
________________________________________________________________________
This section of the FEDERAL REGISTER contains regulatory documents
having general applicability and legal effect, most of which are keyed
to and codified in the Code of Federal Regulations, which is published
under 50 titles pursuant to 44 U.S.C. 1510.
The Code of Federal Regulations is sold by the Superintendent of Documents.
Prices of new books are listed in the first FEDERAL REGISTER issue of each
week.
========================================================================
Federal Register / Vol. 64, No. 22 / Wednesday, February 3, 1999 /
Rules and Regulations
[[Page 5149]]
-----------------------------------------------------------------------
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 98-ANE-73-AD; Amendment 39-11019; AD 99-03-05]
RIN 2120-AA64
Airworthiness Directives; Textron Lycoming Model O-540-F1B5
Reciprocating Engines
AGENCY: Federal Aviation Administration, DOT.
ACTION: Final rule; request for comments.
-----------------------------------------------------------------------
SUMMARY: This amendment adopts a new airworthiness directive (AD) that
is applicable to Textron Lycoming Model O-540-F1B5 reciprocating
engines. This action requires the removal and replacement of the
crankshaft gear retaining bolts. This amendment is prompted by 2
reported failures of the crankshaft gear retaining bolts. The actions
specified in this AD are intended to prevent failure of the crankshaft
gear retaining bolts, which can result in engine failure and subsequent
autorotation and forced landing.
DATES: Effective February 18, 1999.
Comments for inclusion in the Rules Docket must be received on or
before April 5, 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-73-AD, 12 New England
Executive Park, Burlington, MA 01803-5299. Comments may also be sent
via the Internet using the following address: ``9-ad-
[email protected]''. Comments sent via the Internet must contain the
docket number in the subject line.
Information regarding this AD may be examined at the FAA, New
England Region, Office of the Regional Counsel, 12 New England
Executive Park, Burlington, MA.
FOR FURTHER INFORMATION CONTACT: Rocco Viselli, Aerospace Engineer, New
York Aircraft Certification Office, FAA, Engine and Propeller
Directorate, 10 Fifth St., 3rd Floor, Valley Stream, NY 11581-1200;
telephone (516) 256-7531, fax (516) 568-2716.
SUPPLEMENTARY INFORMATION: The Federal Aviation Administration (FAA)
has received reports of 2 failures of the crankshaft gear retaining
bolts on Textron Lycoming Model O-540-F1B5 reciprocating engines,
installed on Robinson R44 series rotorcraft. The investigation revealed
that the head of the retaining bolts sheared off allowing the
crankshaft gear to disengage. The crankshaft gear drives both magnetos
and the camshaft. Failure of the retaining bolt results in total loss
of power without prior warning. The FAA has determined that the 2
crankshaft gear bolts to fail in service failed from a condition known
as hydrogen embrittlement. This condition results from the underbaking
process during manufacturing, which leads to incomplete hydrogen
relief, and as such, the bolts can be susceptible to hydrogen
embrittlement. Therefore, the FAA has determined that this condition
affects only a specific population of retaining bolts, and has
identified by serial number the specific engines that require
replacement of the suspect bolts. This condition, if not corrected,
could result in failure of the crankshaft gear retaining bolts, which
can result in engine failure and subsequent autorotation and forced
landing.
The suspect crankshaft gear retaining bolts must be replaced by
either Textron Lycoming or Robinson Helicopter company maintenance
personnel. In order to allow the removal and replacement of the suspect
bolts without removing the engine from the helicopter, a complex
procedure is required. This procedure requires removal of the accessory
gear case without removal of the oil sump, which is beyond the scope of
current engine service instructions.
Since an unsafe condition has been identified that is likely to
exist or develop on engines of the same type design, this AD is being
issued to prevent crankshaft gear retaining bolt failure. This AD
requires removal and replacement of the crankshaft gear retaining
bolts. The actions are required to be accomplished in accordance with
the service documents described previously.
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-73-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
[[Page 5150]]
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, 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:
99-03-05 Textron Lycoming: Amendment 39-11019. Docket 98-ANE-73-AD.
Applicability: Textron Lycoming Model O-540-F1B5 reciprocating
engines, with the following Textron Lycoming Engine Serial Numbers,
installed on but not limited to Robinson Helicopters Co. Model R-44
rotorcraft.
L-24545-40A L-24628-40A
L-24766-40A L-24772-40A
L-25050-40A L-25052-40A
L-25053-40A L-25054-40A
L-25063-40A L-25064-40A
L-25065-40A L-25066-40A
L-25067-40A L-25068-40A
L-25069-40A L-25070-40A
L-25071-40A L-25072-40A
L-25073-40A L-25074-40A
L-25075-40A L-25076-40A
L-25077-40A L-25078-40A
L-25080-40A L-25081-40A
L-25083-40A L-25084-40A
L-25085-40A L-25086-40A
L-25087-40A L-25088-40A
L-25089-40A L-25090-40A
L-25091-40A L-25092-40A
L-25093-40A L-25094-40A
L-25095-40A L-25096-40A
L-25097-40A L-25098-40A
L-25099-40A L-25100-40A
L-25101-40A L-25102-40A
L-25103-40A L-25104-40A
L-25105-40A L-25106-40A
L-25116-40A L-25117-40A
L-25118-40A L-25119-40A
L-25120-40A L-25121-40A
L-25122-40A L-25123-40A
L-25124-40A L-25125-40A
L-25126-40A L-25127-40A
L-25128-40A L-25129-40A
L-25130-40A L-25131-40A
L-25132-40A L-25133-40A
L-25134-40A L-25135-40A
L-25136-40A L-25137-40A
L-25138-40A L-25139-40A
L-25140-40A L-25141-40A
L-25142-40A L-25143-40A
L-25144-40A L-25145-40A
L-25146-40A L-25149-40A
L-25150-40A L-25154-40A
L-25155-40A L-25156-40A
L-25157-40A L-25158-40A
L-25159-40A L-25160-40A
L-25161-40A L-25162-40A
L-25164-40A L-25166-40A
L-25167-40A L-25168-40A
L-25169-40A L-25170-40A
L-25171-40A L-25172-40A
L-25173-40A L-25174-40A
L-25175-40A L-25176-40A
L-25177-40A L-25178-40A
L-25179-40A L-25180-40A
L-25181-40A L-25182-40A
L-25183-40A L-25184-40A
L-25185-40A L-25186-40A
L-25188-40A L-25189-40A
L-25190-40A L-25191-40A
L-25192-40A L-25193-40A
L-25198-40A L-25200-40A
L-25201-40A L-25202-40A
L-25204-40A L-25206-40A
L-25207-40A L-25208-40A
L-25211-40A L-25212-40A
L-25213-40A L-25214-40A
L-25216-40A L-25217-40A
L-25218-40A L-25219-40A
L-25221-40A L-25222-40A
L-25223-40A L-25228-40A
L-25229-40A L-25230-40A
L-25231-40A L-25232-40A
L-25233-40A L-25234-40A
L-25235-40A L-25236-40A
L-25237-40A L-25238-40A
L-25239-40A L-25240-40A
L-25242-40A L-25243-40A
L-25244-40A L-25246-40A
L-25249-40A L-25250-40A
L-25251-40A L-25252-40A
L-25257-40A
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 (b) 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 crankshaft gear retaining bolts, which
can result in engine failure and subsequent autorotation and forced
landing, accomplish the following:
(a) Within 10 hours time in service, or 3 days after the
effective date of this AD, whichever occurs first, have the
crankshaft gear retaining bolt, part number STD-2209, replaced by
Textron Lycoming or Robinson Helicopter Company.
(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, 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 2: 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.
(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 aircraft to a location where
the requirements of this AD can be accomplished.
(d) This amendment becomes effective on February 18, 1999.
Issued in Burlington, Massachusetts, on January 27, 1999.
Jay J. Pardee,
Manager, Engine and Propeller Directorate, Aircraft Certification
Service.
[FR Doc. 99-2474 Filed 2-2-99; 8:45 am]
BILLING CODE 4910-13-P
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These are dated publication metadata, recorded clauses and literal source observations. Word, model-label, header and reference matches do not establish current legal effect, manufacturer/model identity, aircraft applicability, installed configuration or compliance.
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