[Federal Register Volume 70, Number 217 (Thursday, November 10, 2005)]
[Proposed Rules]
[Pages 68381-68384]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 05-22437]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2005-22594; Directorate Identifier 2005-NE-28-AD]
RIN 2120-AA64


Airworthiness Directives; Rolls-Royce Corporation (formerly 
Allison Engine Company, Allison Gas Turbine Division, and Detroit 
Diesel Allison) 250-B and 250-C Series Turboprop and Turboshaft Engines

AGENCY: Federal Aviation Administration (FAA), Department of 
Transportation (DOT).

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD) 
for Rolls-Royce Corporation 250-B and 250-C series turboprop and 
turboshaft engines with certain part numbers (P/Ns) of gas producer 
rotor assembly tie bolts manufactured by EXTEX Ltd., Pacific Sky Supply 
Inc., Rolls-Royce Corporation (RRC), and Superior Air Parts Inc. This 
proposed AD would require operators to remove from service affected gas 
producer rotor assembly tie bolts. This proposed AD results from eleven 
reports of RRC tie bolt failure due to high cycle fatigue. We are 
proposing this AD to prevent tie bolt failure that could cause loss of 
engine power, resulting in a first stage turbine wheel overspeed and an 
uncontained engine failure.

DATES: We must receive any comments on this proposed AD by January 9, 
2006.

ADDRESSES: Use one of the following addresses to comment on this 
proposed AD.

[[Page 68382]]

     DOT Docket Web site: Go to http://dms.dot.gov and follow 
the instructions for sending your comments electronically.
     Government-wide rulemaking Web site: Go to http://www.regulations.gov and follow the instructions for sending your 
comments electronically.
     Mail: Docket Management Facility; U.S. Department of 
Transportation, 400 Seventh Street, SW., Nassif Building, Room PL-401, 
Washington, DC 20590-0001.
     Fax: (202) 493-2251.
     Hand Delivery: Room PL-401 on the plaza level of the 
Nassif Building, 400 Seventh Street, SW., Washington, DC, between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
    You may examine the comments on this proposed AD in the AD docket 
on the Internet at http://dms.dot.gov.

FOR FURTHER INFORMATION CONTACT:
     Robert Baitoo, Aerospace Engineer, Los Angeles Aircraft 
Certification Office, FAA, Transport Airplane Directorate, 3960 
Paramount Blvd., Lakewood, CA 90712-4137; telephone: (562) 627-5245, 
fax: (562) 627-5210, for questions about, EXTEX Ltd., or Pacific Sky 
Supply Inc. gas producer rotor assembly tie bolts.
     John Tallarovic, Aerospace Engineer, Chicago Aircraft 
Certification Office, FAA, 2300 East Devon Avenue, Des Plaines, IL 
60018-4696; telephone (847) 294-8180; fax (847) 294-7834, for questions 
about RRC gas producer rotor assembly tie bolts.
     Jurgen Priester, Aerospace Engineer, Rotorcraft 
Directorate, FAA, 2601 Meacham Blvd., Fort Worth, Texas, 76137-4298, 
telephone (817) 222-5159, fax (817) 222-5785, for questions about 
Superior Air Part Inc. gas producer rotor assembly tie bolts.

SUPPLEMENTARY INFORMATION:

Comments Invited

    We invite you to send us any written relevant data, views, or 
arguments regarding this proposal. Send your comments to an address 
listed under ADDRESSES. Include ``Docket No. FAA-2005-22594; 
Directorate Identifier 2005-NE-28-AD'' in the subject line of your 
comments. We specifically invite comments on the overall regulatory, 
economic, environmental, and energy aspects of the proposed AD. We will 
consider all comments received by the closing date and may amend the 
proposed AD in light of those comments.
    We will post all comments we receive, without change, to http://dms.dot.gov, including any personal information you provide. We will 
also post a report summarizing each substantive verbal contact with FAA 
personnel concerning this proposed AD. Using the search function of the 
DOT Web site, anyone can find and read the comments in any of our 
dockets, including the name of the individual who sent the comment (or 
signed the comment on behalf of an association, business, labor union, 
etc.). You may review the DOT's complete Privacy Act Statement in the 
Federal Register published on April 11, 2000 (65 FR 19477-78) or you 
may visit http://dms.dot.gov.

Examining the AD Docket

    You may examine the docket that contains the proposal, any comments 
received and, any final disposition in person at the DOT Docket Offices 
between 9 a.m. and 5 p.m., Monday through Friday, except Federal 
holidays. The Docket Office (telephone (800) 647-5227) is located on 
the plaza level of the Department of Transportation Nassif Building at 
the street address stated in ADDRESSES. Comments will be available in 
the AD docket shortly after the Docket Management Facility receives 
them.

Discussion

    The FAA has received eleven reports of failures of RRC manufactured 
tie bolts due to high cycle fatigue. The FAA believes that all of these 
failures are due to the inherent design of the part, which is also 
common to all of the PMA parts. Therefore, this AD requires removal of 
all RR and PMA tie-bolts. RRC has redesigned the tie bolt to minimize 
the risk of failure by high cycle fatigue. RRC manufactured these tie 
bolts under type and production certificate authority. EXTEX Ltd., 
Pacific Sky Supply Inc., and Superior Air Parts Inc. each independently 
manufactured replacement gas producer rotor assembly tie bolts under 
Parts Manufacturer Approval (PMA) authority. There have been no 
reported failures of PMA parts. The engines are installed in single-
engine helicopters, along with several turboprop airplanes. This 
condition, if not corrected, could cause loss of engine power, 
resulting in a first stage turbine wheel overspeed and an uncontained 
engine failure.

FAA's Determination and Requirements of the Proposed AD

    We have evaluated all pertinent information from the four 
manufacturers' safety assessments and have identified an unsafe 
condition that is likely to exist or develop in other RRC 250-B17, -
B17B, -B17C, -B17D, -B17E, -B17F, -B17F/1, -B17F/2, 250-C18, -C20, -
C20B, -C20F, -C20J, -C20R, -C20R/1, -C20R/2, -C20R/4, -C20S, and -C20W 
series turboprop and turboshaft engines that have any of the following 
gas producer rotor assembly tie bolts installed:
     EXTEX Ltd.: P/N A23008020, and E23008020
     Pacific Sky Supply Inc.: P/N 23008020P
     Rolls-Royce Corporation: P/Ns 23008020, 6843388 and 
6876991
     Superior Air Parts Inc.: P/N A23008020
    We are proposing this AD, which would remove these P/N gas producer 
rotor assembly tie bolts as specified in the compliance section of this 
proposed AD.

Costs of Compliance

    About 4,000 RRC 250-B and 250-C Series turboprop and turboshaft 
engines with affected P/Ns of gas producer rotor assembly tie bolts 
manufactured by EXTEX Ltd., Pacific Sky Supply Inc., Rolls-Royce 
Corporation (RRC), and Superior Air Parts Inc. are in the worldwide 
fleet. We estimate that 700 engines installed on aircraft of U.S. 
registry would be affected by this proposed AD. We also estimate that 
it would take about 20 work hours per engine to perform the proposed 
actions, and that the average labor rate is $65 per work hour. Required 
parts would cost about $421 per engine. Based on these figures, we 
estimate the total cost of the proposed AD to U.S. operators to be 
$1,204,700.

Authority for This Rulemaking

    Title 49 of the United States Code specifies the FAA's authority to 
issue rules on aviation safety. Subtitle I, section 106, describes the 
authority of the FAA Administrator. Subtitle VII, Aviation Programs, 
describes in more detail the scope of the Agency's authority.
    We are issuing this rulemaking under the authority described in 
subtitle VII, part A, subpart III, section 44701, ``General 
requirements.'' Under that section, Congress charges the FAA with 
promoting safe flight of civil aircraft in air commerce by prescribing 
regulations for practices, methods, and procedures the Administrator 
finds necessary for safety in air commerce. This regulation is within 
the scope of that authority because it addresses an unsafe condition 
that is likely to exist or develop on products identified in this 
rulemaking action.

Regulatory Findings

    We have determined that this proposed AD would not have federalism

[[Page 68383]]

implications under Executive Order 13132. This proposed AD would 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 the proposed 
regulation:
    1. Is not a ``significant regulatory action'' under Executive Order 
12866;
    2. Is not a ``significant rule'' under the DOT Regulatory Policies 
and Procedures (44 FR 11034, February 26, 1979); and
    3. Would 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 regulatory evaluation of the estimated costs to 
comply with this proposed AD. See the ADDRESSES section for a location 
to examine the regulatory evaluation.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Safety.

The Proposed Amendment

    Under the authority delegated to me by the Administrator, the 
Federal Aviation Administration proposes to amend 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. The FAA amends Sec.  39.13 by adding the following new 
airworthiness directive:

Rolls-Royce Corporation (formerly Allison Engine Company, Allison 
Gas Turbine Division, and Detroit Diesel Allison): Docket No. FAA-
2005-22594; Directorate Identifier 2005-NE-28-AD.

Comments Due Date

    (a) The Federal Aviation Administration (FAA) must receive 
comments on this airworthiness directive (AD) action by January 9, 
2006.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to Rolls-Royce Corporation (formerly Allison 
Engine Company, Allison Gas Turbine Division, and Detroit Diesel 
Allison) 250-B17, -B17B, -B17C, -B17D, -B17E, -B17F, -B17F/1, -B17F/
2, 250-C18, -C20, -C20B, -C20F, -C20J, -C20R, -C20R/1, -C20R/2, -
C20R/4, -C20S, and -C20W series turboprop and turboshaft engines 
with the gas producer rotor assembly tie bolt part numbers (P/Ns) 
listed in the following Table 1, installed:

        Table 1.--Affected Gas Producer Rotor Assembly Tie Bolts
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              Manufacturer                      Affected part Nos.
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EXTEX Ltd. (EXTEX).....................  A23008020 and E23008020.
Rolls-Royce Corporation (RRC)..........  23008020, 6843388 and 6876991.
Superior Air Parts Inc. (SAP)..........  A23008020.
Pacific Sky Supply Inc.................  23008020P.
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    These engines are installed on, but not limited to, aircraft in 
the following Table 2:

                      Table 2.--Applicable Aircraft
------------------------------------------------------------------------
               Helicopter                             Models
------------------------------------------------------------------------
Agusta.................................  A109, A109A, A109A II, A109C.
Arrow Falcon Exporters.................  OH-58A+ and OH-58C.
Bell Textron...........................  206A, 206B, 206L.
Enstrom................................  TH-28, 480, 480B.
Eurocopter France......................  AS355E, AS355F, AS355F1,
                                          AS355F2.
Eurocopter Deutschland.................  BO-105A, BO-105C, BO-105S.
FH-1100 Manufacturing Corp.............  FH-1100.
Garlick................................  OH-58A+ and OH-58C.
McDonnell Douglas Company..............  369D, 369E, 369F, 369H, 369HM,
                                          369HS, 369HE, 500N.
San Joaquin............................  OH-58A+ and OH-58C.
Schweizer..............................  269D.
----------------------------------------
                Aircraft                              Models
----------------------------------------
B-N Group Ltd..........................  BN-2T and BN-2T-4R.
SIAI Marchetti s.r.l...................  SF600, SF600A.
------------------------------------------------------------------------

Unsafe Condition

    (d) This AD results from eleven reports of RRC tie bolt failure 
due to high cycle fatigue. We are issuing this AD to prevent tie 
bolt failure that could cause loss of engine power, resulting in a 
first stage turbine wheel overspeed and an uncontained engine 
failure.

Compliance

    (e) You are responsible for having the actions required by this 
AD performed within the compliance times specified unless the 
actions have already been done.

Remove Gas Producer Rotor Assembly Tie Bolts

    (f) Remove the P/N gas producer rotor assembly tie bolts listed 
in Table 1 of this AD from service the next time they are 
disassembled for any reason, or by October 31, 2011, whichever 
occurs first.
    (g) After the effective date of this AD, do not install any gas 
producer rotor assembly tie bolt P/Ns listed in Table 1 of this AD 
in any RRC 250-B and 250-C Series turboprop and turboshaft engines.

Alternative Methods of Compliance

    (h) The Manager, Los Angeles Aircraft Certification Office, has 
the authority to approve alternative methods of compliance for 
EXTEX, and Pacific Sky Supply Inc. gas producer rotor assembly tie 
bolts addressed in this AD, if requested, using the procedures found 
in 14 CFR 39.19. The Manager,

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Chicago Aircraft Certification Office, has the authority to approve 
alternative methods of compliance for RRC gas producer rotor 
assembly tie bolts addressed in this AD, if requested, using the 
procedures found in 14 CFR 39.19. The Manager, Southwest Special 
Certification Office, has the authority to approve alternative 
methods of compliance for SAP gas producer rotor assembly tie bolts 
addressed in this AD, if requested, using the procedures found in 14 
CFR 39.19.

Material Incorporated by Reference

    (i) None.

Related Information

    (j) RRC Commercial Engine Bulletin (CEB) CEB A-304, CEB A-1371, 
CEB A-72-4076, TP CEB A-176, TP CEB A-1319, TP CEB A-72-2027, 
Revision N/C dated May 23, 2005, and EXTEX Service Bulletin T-090, 
Revision N/C, dated May 23, 2005, pertain to the subject of this AD.

    Issued in Burlington, Massachusetts, on November 4, 2005.
Peter A. White,
Acting Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.
[FR Doc. 05-22437 Filed 11-9-05; 8:45 am]
BILLING CODE 4910-13-P