[Federal Register Volume 66, Number 194 (Friday, October 5, 2001)]
[Proposed Rules]
[Pages 50910-50912]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 01-25078]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98-ANE-38-AD]
RIN 2120-AA64


Airworthiness Directives; Airworthiness Directives; CFM 
International (CFMI) CFM56-2, -2A, -2B, -3, -3B, -3C, -5, -5B, -5C, and 
-7B Series Turbofan Engines

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: The Federal Aviation Administration (FAA) proposes to 
supersede an existing airworthiness directive (AD), that is applicable 
to certain CFM International (CFMI) CFM56 series turbofan engines, that 
currently requires revisions to the Airworthiness Limitations Section 
of applicable Engine Shop Manuals (ESM's) to include required enhanced 
inspection of selected critical life-limited parts at each piece-part 
exposure. This proposal would modify the airworthiness limitations 
section of the manufacturer's manual and an air carrier's approved 
continuous airworthiness maintenance program to incorporate additional 
inspection requirements. The actions specified by this proposed AD are 
intended to prevent critical life-limited rotating engine part failure, 
which could result in an uncontained engine failure and damage to the 
airplane.

DATES: Comments must be received by December 4, 2001.

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-38-AD, 12 New England 
Executive Park, Burlington, MA 01803-5299. 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. Comments may be inspected at this 
location by appointment between 8:00 a.m. and 4:30 p.m., Monday through 
Friday, except Federal holidays.

FOR FURTHER INFORMATION CONTACT: Diane Cook, Aerospace Engineer, Engine 
Certification Office, FAA, Engine and Propeller Directorate, 12 New 
England Executive Park, Burlington, MA 01803-5299; telephone (781) 238-
7138, fax (781) 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 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 98-ANE-38-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. 98-ANE-38-AD, 12 New England Executive 
Park, Burlington, MA 01803-5299.

Discussion

    On June 13, 2000, the FAA issued AD 2000-12-01, Amendment 39-11779 
(65 FR 37031, June 13, 2000), to require revisions to the Airworthiness 
Limitations Section of the applicable Engine Shop Manuals (ESM's) for 
CFMI CFM56-2, -2A, -2B, -3, -3B, -3C -5, -5B, -5C, and -7B series 
turbofan engines by adding additional focused inspection procedures and 
increasing the applicability of the CFM56 engine models requiring 
enhanced inspection of selected critical life-limited parts at each 
piece-part exposure.

Additional Inspection Procedures

    Since the issuance of that AD, CFMI has identified additional 
critical life-limited parts requiring enhanced inspections and has 
developed additional focused inspection procedures applicable to the 
High Pressure Turbine (HPT) disk and the HPT front rotating air seal. 
The mandatory inspections are needed to identify those critical 
rotating parts with conditions, which if allowed to continue in 
service, could result in uncontained failures. This proposal would 
modify the Airworthiness Limitations Section of the applicable ESMs to 
incorporate additional inspection requirements.

Proposed Actions

    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 supersede AD 2001-12-01 to add additional critical 
life-limited parts requiring enhanced inspections at piece part 
opportunity. The inspections would be required at each piece-part 
opportunity.

Economic Analysis

    The FAA estimates that 5,100 CFM56 engines installed on airplanes 
of US registry would be affected by this proposed AD and that there are 
approximately 2, 300 piece part annual inspections that would be 
required. It would take approximately 2, 775 work hours to accomplish 
these inspections. The average labor rate is $60 per work hour. The 
total estimated annual cost of the proposed new inspections on US 
operators is expected to be approximately $166,500.

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

[[Page 50911]]

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 removing Amendment 39-11779 (65 FR 
3731, June 13, 2000), and by adding a new airworthiness directive, to 
read as follows:

CFM International: Docket No. 98-ANE-38-AD. Supersedes AD 2000-12-
01, Amendment 39-11779.

    Applicability: CFM International (CFMI) CFM56-2, -2A, -2B, -3, -
3B, -3C, -5, -5B, -5C, and -7B series turbofan engines, installed on 
but not limited to McDonnell Douglas DC-8 series, Boeing 737 series, 
Airbus Industrie A319, A320, A321, and A340 series, as well as 
Boeing E-3, E-6, and KC-135 (military) series airplanes.

    Note 1: 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 request approval for an 
alternative method of compliance in accordance with paragraph (c) 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 critical life-limited rotating engine part failure, 
which could result in an uncontained engine failure and damage to 
the airplane, accomplish the following:

Inspections

    (a) Within the next 30 days after the effective date of this AD, 
revise the Airworthiness Limitations Section (chapter 05-00-00) of 
Engine Shop Manual (ESM) CFMI-TP.SM.4, for CFM56-2 series engines, 
ESM CFMI-TP.SM.6, for CFM56-2A/-2B series engines, ESM CFMI-TP.SM.5, 
for CFM56-3/-3B/-3C series engines, ESM CFMI-TP.SM.7 for CFM56-5 
series engines, ESM CFMI-TP.SM.9 for CFM56-5B series engines, ESM 
CFMI-TP.SM.8 for CFM56-5C series engines, and ESM CFMI-TP.SM.10 for 
CFM56-7B series engines, and for air carrier operations, revise the 
approved continuous airworthiness maintenance program, by adding the 
following:

``MANDATORY INSPECTIONS

    (1) Perform inspections of the following parts at each piece-
part opportunity in accordance with the Inspection/Check section 
instructions provided in the applicable manual sections listed 
below:

----------------------------------------------------------------------------------------------------------------
                                                                           Engine
              Engine models                          Part name             Manual             Inspection
                                                                           Section
----------------------------------------------------------------------------------------------------------------
All......................................  Fan Disk (All Part Number (P/   72-21-03  Disk Fluorescent Penetrant
                                            N).                                       Inspection (FPI) and Disk
                                                                                      Bore and Dovetail Eddy
                                                                                      Current Inspection (ECI).
All......................................  Fan Shaft (All P/N).........    72-22-01  Magnetic Penetrant
                                                                                      Inspection (MPI).
All......................................  HPT Disk (All P/N)..........    75-52-02  FPI, Disk Bore ECI and Bolt
                                                                                      Hole(s) ECI.
All......................................  HPT Front Rotating Air Seal     72-52-03  FPI, Seal Bore ECI and Bolt
                                            (All P/N).                                Hole(s) ECI.
All......................................  HPC Stage 1-2 Spool (All P/     72-31-04  FPI.
                                            N).
All......................................  HPC Stage 3 Disk (All P/N)..    72-31-05  FPI.
All......................................  HPC Stage 4-9 Spool (All P/     72-31-06  FPI.
                                            N).
All......................................  HPC Front Shaft (All P/N)...    72-31-07  FPI.
All......................................  HPC Comporessor Rear (CDP)      72-52-03  FPI.
                                            Air Seal (All P/N).
All......................................  LPT Stage 1 Disk............    72-54-03  FPI.
All......................................  LPT Stage 2 Disk............    72-54-03  FPI.
All......................................  LPT Stage 3 Disk............    72-54-03  FPI.
All......................................  LPT Stage 4 Disk............    72-54-03  FPI.
All......................................  LPT Rotor Support...........    72-54-05  FPI.
All......................................  LPT Shaft...................    72-55-01  FPI.
All......................................  LPT Stub Shaft..............    72-52-03  FPI.
----------------------------------------------------------------------------------------------------------------

    (2) For the purposes of these mandatory inspections, piece-part 
opportunity means:
    (i) The part is considered completely disassembled when 
accomplished in accordance with the disassembly instructions in the 
manufacturer's engine manual; and
    (ii) The part has accumulated more than 100 cycles in service 
since the last piece-part opportunity inspection, provided that the 
part was not damaged or related to the cause for its removal from 
the engine.''
    (b) Except as provided in paragraph (c) of this AD, and 
notwithstanding contrary provisions in section 43.16 of the Federal 
Aviation Regulations (14 CFR 43.16), these mandatory inspections 
shall be performed only in accordance with the Time Limits section 
of the manufacturer's ESM.

Alternative Methods of Compliance

    (c) 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 Engine Certification Office (ECO). Operators 
shall submit their requests through an appropriate FAA Principal 
Maintenance Inspector (PMI), who may add comments and then send it 
to the ECO.

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

Special Flight Permits

    (d) 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 airplane to a location where 
the requirements of this AD can be accomplished.

[[Page 50912]]

Continuous Airworthiness Maintenance Program

    (e) FAA-certificated air carriers that have an approved 
continuous airworthiness maintenance program in accordance with the 
record keeping requirement of Sec. 121.369 (c) of the Federal 
Aviation Regulations [14 CFR 121.369 (c)] of this chapter must 
maintain records of the mandatory inspections that result from 
revising the Airworthiness Limitations Section of the applicable ESM 
and the air carrier's continuous airworthiness program. 
Alternatively, certificated air carriers may establish an approved 
system of record retention that provides a method for preservation 
and retrieval of the maintenance records that include the 
inspections resulting from this AD, and include the policy and 
procedures for implementing this alternate method in the air 
carrier's maintenance manual required by Sec. 121.369 (c) of the 
Federal Aviation Regulations [14 CFR 121.369 (c)]; however, the 
alternate system must be accepted by the appropriate PMI and require 
the maintenance records be maintained either indefinitely or until 
the work is repeated. Records of the piece-part inspections are not 
required under Sec. 121.380 (a)(2)(vi) of the Federal Aviation 
Regulations [14 CFR 121.380 (a)(2)(vi)]. All other operators must 
maintain the records of mandatory inspections required by the 
applicable regulations governing their operations.

    Note 3: The requirements of this AD have been met when the ESM 
changes are made and air carriers have modified their continuous 
airworthiness maintenance plans to reflect the requirements in the 
applicable ESM.


    Issued in Burlington, Massachusetts, on October 1, 2001.
Jay J. Pardee,
Manager, Engine and Propeller Directorate, Aircraft Certification 
Service.
[FR Doc. 01-25078 Filed 10-4-01; 8:45 am]
BILLING CODE 4910-13-P