[Federal Register Volume 67, Number 202 (Friday, October 18, 2002)]
[Proposed Rules]
[Pages 64328-64330]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 02-26587]


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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, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: The Federal Aviation Administration (FAA) proposes to adopt a 
new airworthiness directive (AD) that is applicable to Rolls-Royce 
Corporation (formerly Allison Engine Company) 501-D series turboprop 
engines. This proposal would require removal from service of certain 
turbine rotor components at reduced life limits. This proposal is 
prompted by the result of recalculated material properties by the 
manufacturer. The actions specified by the proposed AD are intended to 
prevent uncontained turbine rotor failure resulting in in-flight engine 
shutdown and possible damage to the airplane.

DATES: Comments must be received by December 17, 2002.

ADDRESSES: Submit comments in triplicate to the 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. Comments may be inspected at 
this location, by appointment, between 8 a.m. and 4:30 p.m., Monday 
through Friday, except Federal holidays. Comments may also be sent via 
the Internet using the following address: [email protected]. 
Comments sent via the Internet must contain the docket number in the 
subject line.
    The service information referenced in the proposed rule may be 
obtained from Rolls-Royce Corporation, P.O. Box 420, Indianapolis, IN 
46206-0420; telephone (317) 230-6400; fax (317) 230-4243. This 
information may be examined, by appointment, 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

    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 action 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 action must submit a self-addressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket Number 2001-NE-01-AD.'' The postcard will be date stamped and 
returned to the commenter.

Availability of NPRM's

    Any person may obtain a copy of this NPRM by submitting a request 
to the 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.

Discussion

    Before the merger of Allison Engine Company and Rolls-Royce 
Corporation, Allison Engine Company obtained additional material 
properties data to enhance their materials database. The additional 
data showed much higher material property scatter compared to the data 
originally used to calculate the turbine rotor component life limits. 
Comparison of the data with other similar alloys showed the 
manufacturer that the new data, with increased scatter, was indeed 
representative. As a result, the manufacturer has reduced the life 
limits of certain second-stage, third-stage, and fourth-stage turbine 
wheel assemblies, and certain 1st-2nd stage, 2nd-3rd stage, and 3rd-4th 
stage turbine spacer assemblies.

FAA's Determination of an Unsafe Condition and Proposed Actions

    Since an unsafe condition has been identified that is likely to 
exist or develop on other Rolls-Royce Corporation (formerly Allison 
Engine Company) 501-D series turboprop engines of the same type design, 
the proposed AD would require removal from service, and replacement 
with a serviceable part for:
    [sbull] Second-stage turbine wheel assemblies part numbers (P/N's) 
6847142 and 6876892, before or upon accumulating 12,000 cycles-in-
service (CIS), or 16,000 CIS if Allison Engine Company Commercial 
Overhaul Information Letter (COIL) 401, dated May 1978 has been 
complied with.
    [sbull] Third-stage turbine wheel assemblies P/N's 6845883 and 
6849743, before or upon accumulating 10,000 CIS, or 13,000 CIS if COIL 
401, dated May 1978 has been complied with.
    [sbull] Third-stage turbine wheel assembly P/N 6855083, before or 
upon accumulating 10,000 CIS.
    [sbull] Fourth-stage turbine wheel assembly P/N 6876468, before or 
upon accumulating 18,000, or 24,000 CIS if COIL 401, dated May 1978 has 
been complied with.
    [sbull] 1st-2nd stage spacer assemblies P/N's 6844632 and 23033463, 
before or upon accumulating 4,700 CIS.
    [sbull] 1st-2nd stage spacer assembly P/N 23056966, before or upon 
accumulating 8,000 CIS.
    [sbull] 2nd-3rd stage spacer assembly P/N 23033456, before or upon 
accumulating 4,000 CIS.
    [sbull] 3rd-4th stage spacer assembly P/N 6844794 with serial 
number (SN) less than and including KK22951, except KK21556, KK21910, 
KK22814, KK22820, KK22868, and all SN's with an MM prefix, before or 
upon accumulating 5,100 CIS.

Economic Analysis

    There are approximately 930 Rolls-Royce 501-D series turboprop 
engines of the affected design in the worldwide fleet. The FAA 
estimates that 684 engines installed on aircraft of U.S. registry would 
be affected by this proposed AD. The proposed action does not impose 
any additional labor costs if

[[Page 64329]]

performed at the time of scheduled engine overhaul. Required parts 
would cost approximately $45,000 per engine. Based on these figures, 
the total cost of the proposed AD to U.S. operators is estimated to be 
$30,780,000.

Regulatory Analysis

    This proposed rule does not have federalism implications, as 
defined in Executive Order 13132, because it 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. 
Accordingly, the FAA has not consulted with state authorities prior to 
publication of this proposed rule.
    For the reasons discussed above, I certify that this 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) 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. 106(g), 40113, 44701.


Sec.  39.13  [Amended]

    2. Section 39.13 is amended by adding the following new 
airworthiness directive:

Rolls-Royce Corporation: Docket No. 2001-NE-01-AD.
    Applicability: This airworthiness directive (AD) is applicable 
to Rolls-Royce Corporation (formerly Allison Engine Company) 501-D 
series turboprop engines. These engines are installed on, but not 
limited to Lockheed 188 series and 382 series turboprop airplanes, 
and Convair Models 340 and 440 airplanes which have had Rolls-Royce 
Corporation 501-D series turboprop engines installed under a 
Supplemental Type Certificate. These models are commonly referred to 
as Convair 580/580A or 5800 models.

    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 (e) 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: Compliance with this AD is required as indicated, 
unless already done.
    To prevent uncontained turbine rotor failure, resulting in in-
flight engine shutdown and possible damage to the airplane, do the 
following:

501-D13 Series Engines

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

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

    (b) Information on 501-D13 series engine turbine life limits can 
be found in Rolls-Royce Commercial Service Letter (CSL) No. CSL-120, 
Revision No. 52, dated July 22, 2002.

501-D22 Series Engines

    (c) 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 and        Before or upon
 assembly.                       23033463.          accumulating 4,700
                                                    CIS.
-------------------------------
(3) 1st-2nd-stage spacer        23056966.........  Before or upon
 assembly.                                          accumulating 8,000
                                                    CIS.
-------------------------------
(4) 2nd-3rd-stage spacer        23033456.........  Before or upon
 assembly.                                          accumulating 4,000
                                                    CIS.
-------------------------------

[[Page 64330]]

 
(5) 3rd-4th-stage spacer        6844794..........  Before or upon
 assembly.                                          accumulating 5,100
                                                    CIS, with SN less
                                                    than and including
                                                    KK22951, except
                                                    KK21556, KK21910,
                                                    KK22814, KK22820 and
                                                    KK22868, and all
                                                    SN's with an MM
                                                    prefix.
------------------------------------------------------------------------

    (d) Information on 501-D22 series engine turbine life limits can 
be found in Rolls-Royce Commercial Service Letter (CSL) No. CSL-
1001, Revision No. 19, dated July 22, 2002.

Alternative Methods of Compliance

    (e) 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, Chicago Aircraft Certification 
Office (ACO). Operators must submit their request through an 
appropriate FAA Principal Maintenance Inspector, who may add 
comments and then send it to the Manager, ACO.

    Note 2: Information concerning the existence of approved 
alternative methods of compliance with this airworthiness directive, 
if any, may be obtained from the ACO.

Special Flight Permits

    (f) Special flight permits may be issued in accordance with 
Sec. Sec.  21.197 and 21.199 of the Federal Aviation Regulations (14 
CFR 21.197 and 21.199) to operate the airplane to a location where 
the requirements of this AD can be done.

    Issued in Burlington, Massachusetts, on October 11, 2002.
Mark C. Fulmer,
Acting Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.
[FR Doc. 02-26587 Filed 10-17-02; 8:45 am]
BILLING CODE 4910-13-P