[Federal Register Volume 63, Number 96 (Tuesday, May 19, 1998)]
[Rules and Regulations]
[Pages 27452-27455]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-12916]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 97-ANE-54-AD; Amendment 39-10523, AD 98-10-11]
RIN 2120-AA64


Airworthiness Directives; CFM International CFM56-3, -3B, -3C, -
5, -5B, and -5C Series Turbofan Engines

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule; request for comments.

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SUMMARY: This amendment adopts a new airworthiness directive (AD) that 
is applicable to CFM International CFM56-3, -3B, -3C, -5, -5B, and -5C 
series turbofan engines. This action supersedes telegraphic AD T97-25-
51 that currently requires removal of one engine from an aircraft, and 
replacement with a serviceable engine or replacement of parts, if both 
engines are equipped with a specific accessory gearbox (AGB) starter 
gearshaft or transfer gearbox (TGB) input bevel gear, and daily checks 
of the AGB/TGB magnetic chip detector. This amendment is prompted by 
further investigation that has revealed that certain TGB output bevel 
gears and AGB intermediate gear assemblies on CFM56-3, -3B, and -3C 
series engines, and AGB gearshaft cluster spur assemblies on CFM56-5, -
5B, and -5C series engines could also be affected. The actions 
specified by this AD are intended to prevent inflight engine shutdowns 
due to an AGB starter gearshaft, TGB input bevel gear, TGB output bevel 
gear, AGB gearshaft cluster spur assembly or AGB intermediate gear 
assembly failure.

DATES: Effective June 3, 1998.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of June 3, 1998.
    Comments for inclusion in the Rules Docket must be received on or 
before July 20, 1998.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), New England Region, Office of the Regional 
Counsel, Attention: Rules Docket No. 97-ANE-54-AD, 12 New England 
Executive Park, Burlington, MA 01803-5299. Comments may also be sent 
via the Internet using the following address: ``9-ad-
[email protected]''. Comments sent via the Internet must contain 
the docket number in the subject line.
    The service information referenced in this AD may be obtained from 
CFM International, Technical Publications Department, 1 Neumann Way, 
Cincinnati, OH 45215; telephone (513) 552-2981, fax (513) 552-2816. 
This information may be examined at the FAA, New England Region, Office 
of the Regional Counsel, 12 New England Executive Park, Burlington, MA; 
or at the Office of the Federal Register, 800 North Capitol Street, 
NW., suite 700, Washington, DC.

FOR FURTHER INFORMATION CONTACT: Glorianne Messemer, Aerospace 
Engineer, Engine Certification Office, FAA, Engine and Propeller 
Directorate, 12 New England Executive Park, Burlington, MA 01803-5299; 
Telephone (781) 238-7132, Fax (781) 238-7199.

SUPPLEMENTARY INFORMATION: On December 4, 1997, the Federal Aviation 
Administration (FAA) issued telegraphic airworthiness directive (AD) 
T97-25-51, applicable to CFM International (CFMI) CFM56-3, -3B, and -3C 
series turbofan series engines, which requires removal of one engine 
from an aircraft, and replacement with a serviceable engine or 
replacement of parts, if both engines are equipped with a specific 
accessory gearbox (AGB) starter gearshaft or transfer gearbox (TGB) 
input bevel gear. In addition, that telegraphic AD requires daily 
checks of the AGB/TGB magnetic chip detector on engines identified by 
engine serial number (ESN) in the applicability section of that 
telegraphic AD until installation of a serviceable starter gearshaft or 
input bevel gear. That action was prompted by reports of three inflight 
engine shutdowns due to AGB starter gearshaft failures, and reports of 
four findings of TGB input bevel gear cracks that were detected during 
inspections. All seven reports occurred on low time newly delivered 
CFM56-3 series turbofan engines. The engines involved in these reports 
had time in service since new ranging from 213 to 500 hours, and cycles 
in service since new ranging from 153 to 229.
    Preliminary investigation results indicate that the root cause of 
the AGB starter gearshaft failure and TGB input bevel gear cracks may 
stem from the improper cleaning procedure prior to the black oxide 
process during manufacture that causes residual stresses around the 
welding areas that could lead to a crack. That condition, if not 
corrected, could result in inflight engine shutdowns due to an AGB 
starter gearshaft or TGB input bevel gear failure.
    Since the issuance of that telegraphic AD, the FAA has determined 
that certain TGB output bevel gears and AGB intermediate gear 
assemblies on CFM56-3, -3B, and -3C series engines, and AGB gearshaft 
cluster spur assemblies on CFM56-5, -5B, and -5C series engines could 
also be affected. There are 44 total AGB starter gearshafts, 41 total 
TGB input bevel gears, 33 total TGB output bevel gears, 60 total AGB 
gearshaft cluster spur assemblies, and 37 AGB intermediate gear 
assemblies that may be affected. Therefore, this expands the 
applicability of the AD to include those engines with these parts 
installed.
    The FAA has reviewed and approved the technical contents of CFMI 
CFM56-3/-3B/-3C Alert Service Bulletin (ASB) No. 72-A861, Revision 3, 
dated December 3, 1997, that describes procedures for AGB/TGB magnetic 
chip detector inspections. In addition, the FAA has reviewed and 
approved the technical contents of CFMI CFM56-3/-3B/-3C Service 
Bulletin (SB) No. 72-863, Revision 1, dated November 18, 1997; CFMI 
CFM56-3/-3B/-3C SB No. 72-865, dated November 18, 1997;

[[Page 27453]]

CFMI CFM56-3/-3B/-3C SB No. 72-867, dated November 28, 1997; CFMI 
CFM56-3/-3B/-3C SB No. 72-873 Revision 1, dated February 5, 1998; CFMI 
CFM56-5 SB No. 72-523, Revision 1, dated January 30, 1998; CFMI CFM56-
5B SB No. 72-211, Revision 1, dated January 29, 1998; and CFMI CFM56-5C 
SB No. 72-350, Revision 1, dated January 30, 1998. These SBs describe 
procedures for removal and replacement of the AGB starter gearshaft, 
TGB assembly, TGB input bevel gear, TGB output bevel gear, AGB 
gearshaft cluster spur assembly or AGB intermediate gear assembly.
    Since an unsafe condition has been identified that is likely to 
exist or develop on other engines of this same type design, this AD 
supersedes telegraphic AD T97-25-51 to require the removal of one 
engine on twin engine aircraft, and replacement with a serviceable 
engine or replacement of parts, if both engines are equipped with a 
specific AGB starter gearshaft, TGB input bevel gear, TGB output bevel 
gear, or AGB intermediate gear assembly. This AD also requires the 
removal of all necessary engines on four engine aircraft, and 
replacement with a serviceable engine or replacement of the AGB 
gearshaft cluster spur assembly, if more than one affected engine is 
installed on the aircraft. In addition, this AD requires daily checks 
of the AGB/TGB magnetic chip detector on CFM56-3, -3B, and -3C series 
engines identified in Table 1 of CFMI CFM56-3/-3B/-3C SB No. 72-863, 
Revision 1, dated November 18, 1997, or CFMI CFM56-3/-3B/-3C SB No. 72-
867, dated November 28, 1997. If abnormal magnetic particles are found, 
this AD requires, prior to further flight, installation of a 
serviceable AGB starter gearshaft, TGB assembly, TGB input bevel gear, 
or TGB output bevel gear. This AD also requires, within 30 days after 
the effective date of this AD, installation of a serviceable AGB 
starter gearshaft, serviceable TGB assembly, serviceable TGB input 
bevel gear, serviceable TGB output bevel gear, serviceable AGB 
gearshaft cluster spur assembly or an AGB intermediate gear assembly, 
as applicable. Installation of a serviceable AGB starter gearshaft, TGB 
assembly, TGB input bevel gear or output bevel gear, as applicable, 
constitutes terminating action to the daily AGB/TGB magnetic chip 
detector inspections. The calendar end-date was based upon FAA risk 
assessment and parts availability. The actions are required to be 
accomplished in accordance with the service documents described 
previously.
    Since a situation exists that requires the immediate adoption of 
this regulation, it is found that notice and opportunity for prior 
public comment hereon are impracticable, and that good cause exists for 
making this amendment effective in less than 30 days.

Comments Invited

    Although this action is in the form of a final rule that involves 
requirements affecting flight safety and, thus, was not preceded by 
notice and an opportunity for public comment, comments are invited on 
this rule. Interested persons are invited to comment on this 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 under the caption ADDRESSES. All 
communications received on or before the closing date for comments will 
be considered, and this rule may be amended in light of the comments 
received. Factual information that supports the commenter's ideas and 
suggestions is extremely helpful in evaluating the effectiveness of the 
AD action and determining whether additional rulemaking action would be 
needed.
    Comments are specifically invited on the overall regulatory, 
economic, environmental, and energy aspects of the rule that might 
suggest a need to modify the 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 that 
summarizes each FAA-public contact concerned with the substance of this 
AD 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 97-ANE-54-AD.'' The postcard will be date stamped and 
returned to the commenter.
    The regulations adopted herein will 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 final 
rule does not have sufficient federalism implications to warrant the 
preparation of a Federalism Assessment.
    The FAA has determined that this regulation is an emergency 
regulation that must be issued immediately to correct an unsafe 
condition in aircraft, and is not a ``significant regulatory action'' 
under Executive Order 12866. It has been determined further that this 
action involves an emergency regulation under DOT Regulatory Policies 
and Procedures (44 FR 11034, February 26, 1979). If it is determined 
that this emergency regulation otherwise would be significant under DOT 
Regulatory Policies and Procedures, a final regulatory evaluation will 
be prepared and placed in the Rules Docket. A copy of it, if filed, may 
be obtained from the Rules Docket at the location provided under the 
caption ``ADDRESSES.''

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, Safety.

Adoption of the Amendment

    Accordingly, pursuant to the authority delegated to me by the 
Administrator, the Federal Aviation Administration amends 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:

98-10-11  CFM International: Amendment 39-10523. Docket No. 97-ANE-
54-AD. Supersedes telegraphic AD T97-25-51.

    Applicability: CFM International (CFMI) CFM56-3, -3B, and -3C 
series turbofan engines, having any of the engine serial numbers 
(ESNs) identified in Table 1 of CFMI CFM56-3/-3B/-3C Service 
Bulletin (SB) No. 72-863, Revision 1, dated November 18, 1997, Table 
1 of CFMI CFM56-3/-3B/-3C SB No. 72-867, dated November 28, 1997, or 
Table 1 of CFMI CFM56-3/-3B/-3C SB No. 72-873, Revision 1, dated 
February 5, 1998; CFM56-5 series turbofan engines, having any of the 
ESNs identified in Table 1 of CFMI CFM56-5 SB No. 72-523, Revision 
1, dated January 30, 1998; CFM56-5B series turbofan engines, having 
any of the ESNs identified in Table 1 of CFMI CFM56-5B SB No. 72-
211, Revision 1, dated January 29, 1998; and CFM56-5C series 
turbofan engines, having any of the ESNs identified in Table 1 of 
CFMI CFM56-5C SB No. 72-350, Revision 1, dated January 30, 1998. 
These engines are installed on but not limited to Boeing 737 series, 
and Airbus Industrie A319, A320, A321, and A340 series aircraft.

    Note 1: This airworthiness directive (AD) applies to each engine 
identified in the

[[Page 27454]]

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 (i) 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: Required as indicated, unless accomplished 
previously.
    To prevent inflight engine shutdowns due to an accessory gearbox 
(AGB) starter gearshaft, transfer gearbox (TGB) input bevel gear, 
TGB output bevel gear, AGB gearshaft cluster spur assembly or AGB 
intermediate gear assembly failure, accomplish the following:
    (a) For twin engine aircraft that are equipped with both engines 
identified by ESN in Table 1 of the applicable SB noted in the 
Applicability paragraph of this AD, prior to further flight, 
accomplish the following:
    (1) Remove one of the engines, and replace with an engine not 
identified by ESN in Table 1 of the applicable SB noted in the 
Applicability paragraph of this AD; or
    (2) On one of the engines, accomplish the following as 
applicable:
    (i) For CFM56-3, -3B, and -3C series engines:
    (A) Replace the AGB starter gearshaft with a serviceable part, 
as defined in paragraph (h) of this AD, in accordance with CFMI 
CFM56-3/-3B/-3C SB No. 72-863, Revision 1, dated November 18, 1997,
    (B) Replace the TGB assembly with a serviceable part, as defined 
in paragraph (h) of this AD, in accordance with CFMI CFM56-3/-3B/-3C 
SB No. 72-865, dated November 18, 1997; or, replace the TGB input 
bevel gear and/or output bevel gear, as applicable, with a 
serviceable part in accordance with CFMI CFM56-3/-3B/-3C SB No. 72-
867, dated November 28, 1997,
    (C) Replace the AGB intermediate gear assembly with a 
serviceable part, as defined in paragraph (h) of this AD, in 
accordance with CFMI CFM56-3/-3B/-3C SB No. 72-873, Revision 1, 
dated February 5, 1998.
    (ii) For CFM56-5 series engines, replace the gearshaft cluster 
spur assembly with a serviceable part, as defined in paragraph (h) 
of this AD, in accordance with CFMI CFM56-5 SB No. 72-523, Revision 
1, dated January 30, 1998.
    (iii) For CFM56-5B series engines, replace the gearshaft cluster 
spur assembly with a serviceable part, as defined in paragraph (h) 
of this AD, in accordance with CFMI CFM56-5B SB No. 72-211, Revision 
1, dated January 29, 1998.
    (b) For four engine aircraft that are equipped with more than one 
engine identified by ESN in Table 1 of CFMI CFM56-5C SB No. 72-350, 
Revision 1, dated January 30, 1998, prior to further flight, accomplish 
the following:
    (1) Remove at least all but one affected engine from the aircraft, 
and replace with serviceable engines not identified by ESN in Table 1 
of CFMI CFM56-5C SB No. 72-350, Revision 1, dated January 30, 1998; or
    (2) Replace the gearshaft cluster spur assembly with a serviceable 
part, as defined in paragraph (h) of this AD, in accordance with CFMI 
CFM56-5C SB No. 72-350, Revision 1, dated January 30, 1998, on at least 
all but one affected engine.
    (c) For CFM56-3, -3B, and -3C series engines identified by ESN in 
Table 1 of CFMI CFM56-3/-3B/-3C SB No. 72-863, Revision 1, dated 
November 18, 1997, or CFMI CFM56-3/-3B/-3C SB No. 72-867, dated 
November 28, 1997, prior to further flight, and thereafter once per 
calendar day, perform checks of the AGB/TGB magnetic chip detector in 
accordance with CFMI CFM56-3/-3B/-3C Alert Service Bulletin (ASB) No. 
72-A861, Revision 3, dated December 3, 1997. If magnetic particles are 
found to be abnormal in accordance with CFMI CFM56-3/-3B/-3C ASB No. 
72-A861, Revision 3, dated December 3, 1997, prior to further flight, 
accomplish the following as applicable:
    (1) For engines identified by ESN in Table 1 of CFMI CFM56-3/-3B/-
3C SB No. 72-863, Revision 1, dated November 18, 1997, remove the AGB 
starter gearshaft, and replace with a serviceable part, as defined in 
paragraph (h) of this AD, in accordance with CFMI CFM56-3/-3B/-3C SB 
No. 72-863, Revision 1, dated November 18, 1997.
    (2) For engines identified by ESN in Table 1 of CFMI CFM56-3/-3B/-
3C SB No. 72-867, dated November 28, 1997, remove the TGB assembly and 
replace with a serviceable part, as defined in paragraph (h) of this 
AD, in accordance with CFMI CFM56-3/-3B/-3C SB No. 72-865, dated 
November 18, 1997; or, remove the TGB input bevel gear and/or TGB 
output bevel gear, as applicable, and replace with serviceable parts, 
as defined in paragraph (h) of this AD, in accordance with CFMI CFM56-
3/-3B/-3C SB No. 72-867, dated November 28, 1997.
    (d) For CFM56-3, -3B, and -3C series engines identified by ESN in 
Table 1 of CFMI CFM56-3/-3B/-3C SB No. 72-863, Revision 1, dated 
November 18, 1997, remove the AGB starter gearshaft within 30 days 
after the effective date of this AD, and replace with a serviceable 
part, as defined in paragraph (h) of this AD, in accordance with CFMI 
CFM56-3/-3B/-3C SB No. 72-863, Revision 1, dated November 18, 1997. 
Installation of a serviceable AGB starter gearshaft, as defined in 
paragraph (h) of this AD, and compliance with paragraph (e) of this AD, 
if applicable, constitutes terminating action to the daily AGB/TGB 
magnetic chip detector checks required by paragraph (c) of this AD.
    (e) For CFM56-3, -3B, and -3C series engines identified by ESN in 
Table 1 of CFMI CFM56-3/-3B/-3C SB No. 72-867, dated November 28, 1997, 
remove the TGB assembly in accordance with CFMI CFM56-3/-3B/-3C SB No. 
72-865, dated November 18, 1997; or, remove the TGB input bevel gear 
and/or output bevel gear, as applicable, within 30 days after the 
effective date of this AD, and replace with serviceable parts, as 
defined in paragraph (h) of this AD, in accordance with CFMI CFM56-3/-
3B/-3C SB No. 72-867, dated November 28, 1997. Installation of a 
serviceable TGB assembly, or TGB input bevel gear and/or TGB output 
bevel gear, as defined in paragraph (h) of this AD, and compliance with 
paragraph (d) of this AD if applicable, constitutes terminating action 
to the daily AGB/TGB magnetic chip detector checks required by 
paragraph (c) of this AD.
    (f) For CFM56-3, -3B, and -3C series engines identified by ESN in 
Table 1 of CFMI CFM56-3/-3B/-3C SB No. 72-873, Revision 1, dated 
February 5, 1998, remove the AGB intermediate gear assembly within 30 
days after the effective date of this AD, and replace with a 
serviceable part, as defined in paragraph (h) of this AD, in accordance 
with CFMI CFM56-3/-3B/-3C SB No. 72-873, Revision 1, dated February 5, 
1998.
    (g) For CFM56-5, -5B, and -5C series engines identified by ESN in 
Table 1 of CFMI CFM56-5 SB No. 72-523, Revision 1, dated January 30, 
1998, CFMI CFM56-5B SB No. 72-211, Revision 1, dated January 29, 1998, 
or CFMI CFM56-5C SB No. 72-350, Revision 1, dated January 30, 1998, 
remove the gearshaft cluster spur assembly within 30 days after the 
effective date of this AD, and replace with a serviceable part, as 
defined in paragraph (h) of this AD, in accordance with CFMI CFM56-5 SB 
No. 72-523, Revision 1, dated January 30, 1998, CFMI CFM56-5B SB No. 
72-211, Revision 1, dated January 29, 1998, or CFMI CFM56-5C SB No. 72-
350, Revision 1, dated January 30, 1998, as applicable.
    (h) For the purposes of this AD, a serviceable part is defined as 
an AGB starter gearshaft, Part Number (P/N) 335-302-503-0, a TGB 
assembly, P/N 335-300-012-0, a TGB input bevel gear, P/N 335-321-008-0, 
a TGB output bevel gear, P/N 335-322-405-0, AGB gearshaft cluster spur 
assembly, P/N 335-302-503-0, or an AGB intermediate gear assembly, P/N 
335-303-202-0, not

[[Page 27455]]

identified by part serial number in Table 1 of the applicable SB noted 
in the Applicability Section of this AD.
    (i) An alternative method of compliance or adjustment of the 
initial 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 Principal 
Maintenance Inspector, who may add comments and then send it to the 
Manager, Engine Certification Office.

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

    (j) The actions required by this AD shall be accomplished in 
accordance with the following CFMI service documents:

----------------------------------------------------------------------------------------------------------------
           Document No.                       Page                    Revision                    Date          
----------------------------------------------------------------------------------------------------------------
CFM56-3/-3B/-3C ASB No. 72-A861..  1-10.....................  3.......................  Dec. 3, 1997.           
    Total Pages: 10                                                                                             
CFM56-3/-3B/-3C SB No. 72-863....  1-39.....................  1.......................  Nov. 18, 1997.          
    Total Pages: 39                                                                                             
CFM56-3/-3B/-3C SB No. 72-865....  1-8......................  Original................  Nov. 18, 1997.          
    Total Pages: 8                                                                                              
CFM56-3/-3B/-3C SB No. 72-867....  1-11.....................  Original................  Nov. 28, 1997.          
    Total Pages: 11                                                                                             
CFM56-3/-3B/-3C SB No. 72-873....  1-21.....................  1.......................  Feb. 5, 1998.           
    Total Pages: 21                                                                                             
CFM56-5 SB No. 72-523............  1-33.....................  1.......................  Jan. 30, 1998.          
    Total Pages: 33                                                                                             
CFM56-5B SB No. 72-211...........  1-28.....................  1.......................  Jan. 29, 1998.          
    Total Pages: 28                                                                                             
CFM56-5C SB No. 72-350...........  1-28.....................  1.......................  Jan. 30, 1998.          
    Total Pages: 28                                                                                             
----------------------------------------------------------------------------------------------------------------

This incorporation by reference was approved by the Director of the 
Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 
51. Copies may be obtained from CFM International, Technical 
Publications Department, 1 Neumann Way, Cincinnati, OH 45215; 
telephone (513) 552-2981, fax (513) 552-2816. Copies may be 
inspected at the FAA, New England Region, Office of the Regional 
Counsel, 12 New England Executive Park, Burlington, MA; or at the 
Office of the Federal Register, 800 North Capitol Street, NW., suite 
700, Washington, DC.
    (k) This amendment supersedes telegraphic AD T97-25-51, issued 
December 4, 1997.
    (l) This amendment becomes effective on June 3, 1998.

    Issued in Burlington, Massachusetts, on May 7, 1998.
Thomas A. Boudreau,
Acting Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.
[FR Doc. 98-12916 Filed 5-18-98; 8:45 am]
BILLING CODE 4910-13-U