[Federal Register Volume 71, Number 35 (Wednesday, February 22, 2006)]
[Proposed Rules]
[Pages 9048-9050]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: E6-2454]


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

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2001-NE-01-AD]
RIN 2120-AA64


Airworthiness Directives; Rolls-Royce Corporation (Formerly 
Allison Engine Company) 501-D Series Turboprop Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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

SUMMARY: The FAA proposes to supersede an existing airworthiness 
directive (AD) for Rolls-Royce Corporation (formerly Allison Engine 
Company) (RRC) 501-D series turboprop engines. That AD currently 
requires removal from service of certain turbine rotor components at 
reduced life limits. This proposed AD would require the same actions 
but adds two new life limits. This proposed AD results from RRC 
reevaluating and revising component life limits for 501-D22 series 
turboprop engines. We are proposing this AD to prevent uncontained 
turbine rotor failure resulting in an in-flight engine shutdown and 
possible damage to the airplane.

DATES: We must receive any comments on this proposed AD by April 24, 
2006.

ADDRESSES: Use one of the following addresses to submit comments on 
this proposed AD:
     By mail: Federal Aviation Administration (FAA), New 
England Region, Office of the Regional Counsel, Attention: Rules Docket 
No. 2001-NE-01-AD, 12 New England Executive Park, Burlington, MA 01803-
5299.
     By fax: (781) 238-7055.
     By e-mail: [email protected].
    You can get the service information identified in this proposed AD 
from Rolls-Royce Corporation, P.O. Box 420, Indianapolis, IN 46206-
0420; telephone (317) 230-6400; fax (317) 230-4243.
    You may examine the AD docket at the FAA, New England Region, 
Office of the Regional Counsel, 12 New England Executive Park, 
Burlington, MA.

FOR FURTHER INFORMATION CONTACT: Michael Downs, Aerospace Engineer, 
Chicago Aircraft Certification Office, FAA, 2300 East Devon Avenue, Des 
Plaines, IL 60018; telephone (847) 294-7870; fax (847) 294-7834.

SUPPLEMENTARY INFORMATION:

Comments Invited

    We invite you to submit any written relevant data, views, or 
arguments regarding this proposal. Send your comments to an address 
listed under ADDRESSES. Include ``AD Docket No. 2001-NE-01-AD'' in the 
subject line of your comments. If you want us to acknowledge receipt of 
your mailed comments, send us a self-addressed, stamped postcard with 
the docket number written on it; we will date-stamp your postcard and 
mail it back to you. We specifically invite comments on the overall 
regulatory, economic, environmental, and energy aspects of the proposed 
AD. If a person contacts us verbally, and that contact relates to a 
substantive part of this proposed AD, we will summarize the contact and 
place the summary in the docket. We will consider all comments received 
by the closing date and may amend the proposed AD in light of those 
comments.

Examining the AD Docket

    You may examine the AD Docket (including any comments and service 
information), by appointment, between 8 a.m. and 4:30 p.m., Monday 
through Friday, except Federal holidays. See ADDRESSES for the 
location.

Discussion

    On March 25, 2003, we issued AD 2003-07-02, Amendment 39-13098 (68 
FR 15937, April 2, 2003). That AD requires removing from service 
certain turbine rotor components at reduced life limits. That AD 
resulted from RRC updating material properties and recalculating 
component life limits. That condition, if not corrected, could result 
in uncontained turbine rotor

[[Page 9049]]

failure resulting in an in-flight engine shutdown and possible damage 
to the airplane.

Actions Since AD 2003-07-02 Was Issued

    Since we issued AD 2003-07-02, RRC reevaluated turbine wheel 
assembly and turbine wheel spacer assembly life limits for 501-D series 
turboprop engines. RRC changed certain life limits for the 501-D22 
series turboprop engines because of recent improvements in how low-
cycle-fatigue life is determined. RRC similarly reduced the life limit 
of 2nd-3rd-stage spacer assemblies, part numbers (P/Ns) 23033464 and 
6842683, installed on 501-D22 series turboprop engines.

FAA's Determination and Requirements of the Proposed AD

    We have evaluated all pertinent information and identified an 
unsafe condition that is likely to exist or develop on other products 
of this same type design. We are proposing this AD, which would require 
the same actions specified in AD 2003-07-02, but for 501-D22 series 
turboprop engines, it would add a life limit of 5,200 cycles-in-service 
for 2nd-3rd-stage spacer assemblies, P/Ns 23033464 and 6842683.

Costs of Compliance

    We estimate that this proposed AD would affect 684 engines 
installed on aircraft of U.S. registry. The proposed action does not 
impose any additional labor costs if performed at the time of scheduled 
engine overhaul. Required parts would cost about $45,000 per engine. 
Based on these figures, we estimate the total cost of the proposed AD 
to U.S. operators to be $30,780,000.

Special Flight Permits Paragraph Removed

    Paragraph (f) of the current AD, AD 2003-07-02, contains a 
paragraph pertaining to special flight permits. Even though this 
proposed AD does not contain a similar paragraph, we have made no 
changes with regard to the use of special flight permits to operate the 
airplane to a repair facility to do the work required by this proposed 
AD. In July 2002, we published a new Part 39 that contains a general 
authority regarding special flight permits and airworthiness 
directives; see Docket No. FAA-2004-8460, Amendment 39-9474 (69 FR 
47998, July 22, 2002). Thus, when we now supersede ADs we will not 
include a specific paragraph on special flight permits unless we want 
to limit the use of that general authority granted in section 39.23.

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 
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 summary of the costs to comply with this proposal 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. 2001-NE-01-AD'' in your request.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Safety.

The Proposed Amendment

    Accordingly, 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 removing Amendment 39-13098 (68 FR 
15937, April 2, 2003) and by adding a new airworthiness directive to 
read as follows:

Rolls-Royce Corporation: Docket No. 2001-NE-01-AD.

Comments Due Date

    (a) The Federal Aviation Administration (FAA) must receive 
comments on this airworthiness directive (AD) action by April 24, 
2006.

Affected ADs

    (b) This AD supersedes AD 2003-07-02, Amendment 39-13098.

Applicability

    (c) This AD applies to Rolls-Royce Corporation (formerly Allison 
Engine Company) (RRC) 501-D series turboprop engines. These engines 
are installed on, but not limited to, Lockheed 188 series and 382 
series turboprop airplanes, Airbus 377SG5-F (Super Guppy) airplanes, 
and Convair Models 340 and 440 airplanes which have RRC 501-D series 
turboprop engines installed under Supplemental Type Certificate No. 
SE1161EA. These latter models are commonly referred to as Convair 
580/580A or 5800 models.
    (d) This AD results from RRC reevaluating and revising component 
life limits for 501-D22 series turboprop engines. We are issuing 
this AD to prevent uncontained turbine rotor failure resulting in an 
in-flight engine shutdown and possible damage to the airplane.

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.

501-D13 Series Engines

    (f) For 501-D13 series engines, remove turbine wheels and 
spacers from service as specified in the following Table 1:

[[Page 9050]]



                                      Table 1.--501-D13 Series Life Limits
----------------------------------------------------------------------------------------------------------------
                                                                 Life limit for wheels
                                                                that have complied with   Life limit for wheels
                                                                  commercial overhaul     that have not complied
           Part name                      Part number              information letter      with COIL 401, dated
                                                                 (COIL) 401, dated May           May 1978
                                                                          1978
----------------------------------------------------------------------------------------------------------------
(1) Second-stage turbine wheel   6847142 and 6876892..........  Remove from service      Remove from service
 assembly.                                                       before or upon           before or upon
                                                                 accumulating 16,000      accumulating 12,000
                                                                 cycles-in-service        CIS.
                                                                 (CIS).
(2) Third-stage turbine wheel    6845883 and 6849743..........  Remove from service      Remove from service
 assembly.                                                       before or upon           before or upon
                                                                 accumulating 13,000      accumulating 10,000
                                                                 CIS.                     CIS.
(3) Fourth-stage turbine wheel   6876468......................  Remove from service      Remove from service
 assembly.                                                       before or upon           before or upon
                                                                 accumulating 24,000      accumulating 18,000
                                                                 CIS.                     CIS.
----------------------------------------------------------------------------------------------------------------

501-D22 Series Engines

    (g) For 501-D22 series engines, remove turbine wheels and 
spacers from service as specified in the following Table 2:

                  Table 2.--501-D22 Series Life Limits
------------------------------------------------------------------------
           Part name               Part number      Remove from service
------------------------------------------------------------------------
(1) Third-stage turbine wheel   6855083..........  Before or upon
 assembly.                                          accumulating 10,000
                                                    cycles-in-service
                                                    (CIS).
(2) 1st-2nd-stage spacer        6844632,           Before or upon
 assembly.                       23033463,          accumulating 4,700
                                 23064854, and      CIS.
                                 23064858.
(3) 1st-2nd-stage spacer        23056966.........  (i) Before or upon
 assembly.                                          accumulating 8,000
                                                    CIS.
                                                   (ii) If the 1st-2nd-
                                                    stage spacer
                                                    assembly passes the
                                                    hardness criteria in
                                                    RRC Commercial
                                                    Engine Bulletin CEB-
                                                    A-72-1135, then
                                                    before or upon
                                                    accumulating 10,000
                                                    CIS.
(4) 2nd-3rd-stage spacer        23033456.........  Before or upon
 assembly.                                          accumulating 4,200
                                                    CIS.
(5) 2nd-3rd-stage spacer        23033464 and       Before or upon
 assembly.                       6842683.           accumulating 5,200
                                                    CIS.
(6) 3rd-4th-stage spacer        6844794 prior to   Before or upon
 assembly.                       revision letter    accumulating 5,100
                                 ``R''.             CIS.
------------------------------------------------------------------------

Alternative Methods of Compliance

    (h) The Manager, Chicago 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.

Related Information

    (i) Information on 501-D13 series engine turbine life limits can 
be found in RRC Commercial Service Letter (CSL) No. CSL-120, 
Revision No. 52, dated July 22, 2002.
    (j) Information on 501-D22 series engine turbine life limits can 
be found in RRC CSL No. CSL-1001, Revision No. 20, dated April 5, 
2005.

    Issued in Burlington, Massachusetts, on February 14, 2006.
Ann C. Mollica,
Acting Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.
 [FR Doc. E6-2454 Filed 2-21-06; 8:45 am]
BILLING CODE 4910-13-P