AD Amdt-39-11019

final rule

Airworthiness Directives; Textron Lycoming Model O-540-F1B5 Reciprocating Engines

AD Number
Amdt-39-11019
Status
final_rule
Effective Date
Product Category
engine
Docket
Docket No. 98-ANE-73-AD
FR Citation
64 FR 5149
Technical illustration of an aircraft turbine engine assembly
Problem area Engine

Applicability

TypeManufacturerModelDetails
aircraft Textron O-540-F1B5 Airworthiness Directives; Textron Lycoming Model O-540-F1B5 Reciprocating Engines
engine Lycoming O-540-F1B5 Reciprocating Airworthiness Directives; Textron Lycoming Model O-540-F1B5 Reciprocating Engines

Unsafe Condition

Failure of the crankshaft gear retaining bolts can result in engine failure, leading to autorotation and forced landing.

AI-generated summary from the source AD text. Verify against the official source before acting.

Required Actions

Remove and replace the crankshaft gear retaining bolts.

AI-generated summary from the source AD text. Verify against the official source before acting.

Compliance Time

Before further flight.

AI-generated summary from the source AD text. Verify against the official source before acting.

Affected Aircraft

Textron Lycoming Model O-540-F1B5 reciprocating engines.

AI-generated summary from the source AD text. Verify against the official source before acting.

Federal Register Abstract

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.

Document Text

Show stored source text (verify against official source)
[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 [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[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 
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Federal Register / Vol. 64, No. 22 / Wednesday, February 3, 1999 / 
Rules and Regulations

[[Page 5149]]


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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: ``<a href="/cdn-cgi/l/email-protection#576e7a36337a5d3239303e3932272538271731363679303821">9-ad-
<span class="__cf_email__" data-cfemail="f3969d949a9d9683819c83b3959292dd949c85">[email&#160;protected]</span></a>''. 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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