[Federal Register Volume 60, Number 97 (Friday, May 19, 1995)]
[Proposed Rules]
[Pages 26846-26848]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 95-12330]



      
 ========================================================================
 Proposed Rules
                                                 Federal Register
 ________________________________________________________________________
 
 This section of the FEDERAL REGISTER contains notices to the public of 
 the proposed issuance of rules and regulations. The purpose of these 
 notices is to give interested persons an opportunity to participate in 
 the rule making prior to the adoption of the final rules.
 
 ========================================================================
 

  Federal Register / Vol. 60, No. 97 / Friday, May 19, 1995 / Proposed 
Rules  

[[Page 26846]]

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 95-ANE-08]


Airworthiness Directives; AlliedSignal Engines (Formerly Textron 
Lycoming) Models LTS101-650B1, -750B1, -650C, and -750C Turboshaft 
Engines

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

-----------------------------------------------------------------------

SUMMARY: This document proposes the adoption of a new airworthiness 
directive (AD) that is applicable to AlliedSignal Engines (formerly 
Textron Lycoming) Models LTS101-650B1, -750B1, -650C, and -750C 
turboshaft engines. This proposal would require installation of an 
improved power turbine (PT) rotor and electronic PT rotor overspeed 
controller as a terminating action to the currently required 
inspections of AD 88-14-01. This proposal is prompted by reports of 
additional bearing failures since publication of AD 88-14-01, including 
one additional uncontained PT disk failure. The actions specified by 
the proposed AD are intended to prevent PT overspeed and uncontained 
engine failure.

DATES: Comments must be received by July 18, 1995.

.ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), New England Region, Office of the Assistant Chief 
Counsel, Attention: Rules Docket No. 95-ANE-08, 12 New England 
Executive Park, Burlington, MA 01803-5299. Comments may be inspected at 
this location between 8:00 a.m. and 4:30 p.m., Monday through Friday, 
except Federal holidays.
    The service information referenced in the proposed rule may be 
obtained from AlliedSignal Inc., 550 Main Street, Stratford, CT 06497. 
This information may be examined at the FAA, New England Region, Office 
of the Assistant Chief Counsel, 12 New England Executive Park, 
Burlington, MA.

FOR FURTHER INFORMATION CONTACT: Eugene Triozzi, Aerospace Engineer, 
Engine Certification Office, FAA, Engine and Propeller Directorate, 12 
New England Executive Park, Burlington, MA 01803-5299; telephone (617) 
238-7148, fax (617) 238-7199.

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 should 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 95-ANE-08.'' 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, New England Region, Office of the Assistant Chief Counsel, 
Attention: Rules Docket No. 95-ANE-08, 12 New England Executive Park, 
Burlington, MA 01803-5299.

Discussion

    On May 26, 1988, the Federal Aviation Administration (FAA) issued 
airworthiness directive (AD) 88-14-01, Amendment 39-5952 (53 FR 25317, 
July 6, 1988), to require initial and repetitive inspections of the 
engine lubrication and bearing systems on AlliedSignal Engines 
(formerly Textron Lycoming) LTS101 series turboshaft engines. That 
action was prompted by reports of four uncontained power turbine (PT) 
disk failures. Subsequent investigation revealed that the PT disk 
failures were caused by bearing failures resulting in PT shaft 
disengagement from the gear train drive, unloading the PT and causing 
rotor overspeed. Two other PT disk failures involved No. 4 bearing 
failure, followed by power pinion gear teeth failure, thereby unloading 
the PT and causing PT rotor overspeed. This condition, if not 
corrected, could result in PT overspeed and uncontained engine failure.
    Since the issuance of that AD, the FAA has received reports of 
additional bearing failures with resultant loss of PT rotor location, 
including one additional uncontained PT disk failure. In order to 
minimize the possibility of an uncontained engine failure, the 
manufacturer has developed an improved PT rotor with retention 
capability and an improved electronic PT rotor overspeed controller. 
These improvements are only available for AlliedSignal Engines Models 
LTS101-650B1, -750B1, -650C, and -750C turboshaft engines, installed on 
Bell Helicopter Textron 222 series and Messerschmitt-Bolkow-Blohm (MBB) 
BK117 series helicopters. Installation of these improved components 
constitutes terminating action to the inspections required by AD 88-14-
01 only to these certain engine models installed on these certain 
helicopters.
    On October 28, 1994, AlliedSignal Inc. purchased the turbine engine 
product line of Textron Lycoming.
    The FAA has reviewed and approved the technical contents of the 
following Textron Lycoming Service Bulletins (SB), that describe 
installing an improved PT rotor with retention capability and an 
electronic PT rotor overspeed controller:

                                                                                                                
[[Page 26847]]
----------------------------------------------------------------------------------------------------------------
       Engine model                          PT rotor                             Electronic overspeed          
----------------------------------------------------------------------------------------------------------------
LTS101-650B...............  LTS101B-72-50-0122, Revision 4, dated      LTS101B-73-10-0127, Revision 2, dated    
                             June 17, 1991.                             August 14, 1992.                        
LTS101-750B1..............  LTS101B-72-50-0116, Revision 6, dated      LTS101B-73-10-0127, Revision 2 dated     
                             August 14, 1992.                           August 14, 1992.                        
LTS101-650C and -750        LTS101C-72-50-0119, Revision 2, dated      LTS101C-73-10-0129, Revision 3, dated    
 Series.                     June 17, 1991.                             August 14, 1992.                        
----------------------------------------------------------------------------------------------------------------

  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 installation of an improved PT rotor with 
retention capability and an electronic PT rotor overspeed controller at 
the next shop visit when the PT rotor is removed after the effective 
date of this AD, but prior to December 31, 1997, as a terminating 
action to the currently required inspections of AD 88-14-01. The FAA 
has determined, based on the availability of parts, that by that date 
affected engines would have at least one scheduled shop visit to 
install the improved components. In addition, by that date operators 
would have at least one scheduled opportunity to install components of 
the electronic overspeed controller in affected aircraft. The actions 
would be required to be accomplished in accordance with the service 
bulletins described previously.
    There are approximately 950 engines of the affected design in the 
worldwide fleet. The FAA estimates that 95 engines installed on 
aircraft of U.S. registry would be affected by the requirement to 
install the PT rotor with improved retention, that it would take 
approximately 10 work hours per engine to accomplish the proposed 
action, and that the average labor rate is $60 per work hour. Required 
parts cost for the PT rotor installation would be $44,400 per engine. 
Based on these figures, the cost impact of installing the PT rotor with 
improved retention is estimated to be $4,275,000.
    In addition, the FAA estimates that 576 engines installed on 
aircraft of U.S. registry would be affected by the requirement to 
install the electronic PT rotor overspeed controller, that it would 
take approximately 3 work hours per engine to accomplish the proposed 
action, and that the average labor rate is $60 per work hour. Required 
parts cost for the electronic PT rotor overspeed controller 
installation would be $5,825. Based on these figures, the cost impact 
of installing the electronic PT rotor overspeed controller would be 
$3,458,880. Therefore, the total cost impact of all the actions of the 
proposed AD on U.S. operators is estimated to be $7,733,880.
    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 ``major rule'' under Executive Order 12291; (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:

AlliedSignal Engines: Docket No. 95-ANE-08.

    Applicability: AlliedSignal Engines (formerly Textron Lycoming) 
Model LTS101-650B1, -750B1, -650C, and -750C turboshaft engines 
installed on Bell Helicopter Textron 222 series and Messerschmitt-
Bolkow-Blohm (MBB) BK117 series helicopters.

    Note: This 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 use the authority provided in paragraph (d) 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 engine from the 
applicability of this AD.
    Compliance: Required as indicated, unless accomplished 
previously.
    To prevent power turbine (PT) overspeed and uncontained engine 
failure, accomplish the following:
    (a) Install the improved PT rotor with retention capability at 
the next shop visit when the PT rotor is removed after the effective 
date of this AD, but prior to December 31, 1997, in accordance with 
the following Textron Lycoming Service Bulletins (SB):

----------------------------------------------------------------------------------------------------------------
                 Engine model                               SB No.               Rev.             Date          
----------------------------------------------------------------------------------------------------------------
LTS101-650B1..................................  LTS101B-72-50-0122                   4  June 17, 1991.          
LTS101-750B1..................................  LTS101B-72-50-0116                   6  August 14, 1992.        
LTS101-650C and -750C Series..................  LTS101C-72-50-0119                   2  June 17, 1991.          
----------------------------------------------------------------------------------------------------------------

    (b) Install the improved electronic PT rotor overspeed 
controller concurrently with the PT rotor installation required by 
paragraph (a) of this AD in accordance with the following Textron 
Lycoming SB:

                                                                                                                
[[Page 26848]]
----------------------------------------------------------------------------------------------------------------
                 Engine model                               SB No.               Rev.             Date          
----------------------------------------------------------------------------------------------------------------
LTS101-650B1..................................  LTS101-73-10-0127                    2  August 14, 1992.        
LTS101-750B1..................................  LTS101-73-10-0127                    2  August 14, 1992.        
LTS101-650C and -750C Series..................  LTS101-73-10-0129                    3  August 14, 1992.        
----------------------------------------------------------------------------------------------------------------

  (c) Installation of the improved PT rotor with retention 
capability and the improved electronic PT rotor overspeed controller 
in accordance with paragraphs (a) and (b) of this AD constitutes 
terminating action to the inspection requirements of AD 88-14-01.

    (d) 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, Engine Certification Office. The 
request should be forwarded through an appropriate FAA Maintenance 
Inspector, who may add comments and then send it to the Manager, 
Engine Certification Office.


    Note: Information concerning the existence of approved 
alternative methods of compliance with this airworthiness directive, 
if any, may be obtained from the Engine Certification Office.

    (e) 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.

    Issued in Burlington, Massachusetts, on May 15, 1995.

James C. Jones,

Acting Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.

[FR Doc. 95-12330 Filed 5-18-95; 8:45 am]

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