[Federal Register Volume 63, Number 176 (Friday, September 11, 1998)]
[Rules and Regulations]
[Pages 48573-48575]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-24183]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98-ANE-44-AD; Amendment 39-10752; AD 98-19-10]
RIN 2120-AA64


Airworthiness Directives; CFM International CFM56-3, -3B, and -3C 
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 (CFMI) CFM56-3, -3B, and -3C series 
turbofan engines. This action requires, on aircraft with two affected 
engines installed, removal of one affected engine from an aircraft, and 
replacement with a serviceable engine, or replacement of a suspect 
accessory gearbox (AGB) starter gearshaft with a serviceable gearshaft 
within 350 hours time in service (TIS) after the effective date of this 
AD, or by September 1, 1998, whichever occurs first. This action also 
requires, on aircraft with only one affected engine installed, removal 
of the affected engine from the aircraft, and replacement with a 
serviceable engine , or replacement of thea suspect starter gearshaft 
with a serviceable gearshaft within 2,100 hours TIS after the effective 
date of this AD, or by February 1, 1999, whichever occurs first. This 
amendment is prompted by reports of two inflight engine shutdowns 
caused by an AGB starter gearshaft failure. The actions specified in 
this AD are intended to prevent an AGB starter gearshaft failure, which 
can result in an inflight engine shutdown, and on aircraft with two 
affected engines installed, possible dual inflight engine shutdown and 
forced landing.

DATES: Effective September 28, 1998.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of September 28, 1998.
    Comments for inclusion in the Rules Docket must be received on or 
before November 10, 1998.

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-44-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: The Federal Aviation Administration (FAA) 
has received reports of two inflight engine shutdowns on CFM 
International (CFMI) CFM56-3, -3B, and -3C series turbofan engines. The 
investigation revealed that the inflight engine shutdowns were caused 
by an accessory gearbox (AGB) starter gearshaft failure. The 
investigation revealed that the gearshafts failed due to inadequate 
fatigue capability caused by high residual tensile stresses introduced 
during the manufacturing process, coupled with the elimination of 
shotpeening in the gearshaft hub. The manufacturing process has since 
been modified. The starter gearshaft, part number 335-302-503-0, 
involved in the events are included in a lot of 426 parts that have 
since been identified by the manufacturer as being installed on engines 
identified by engine serial number (ESN). This condition, if not 
corrected, could result in an AGB starter gearshaft failure, which can 
result in an inflight engine shutdown, and on aircraft with two 
affected engines

[[Page 48574]]

installed, possible dual inflight engine shutdown and forced landing.
    The FAA has reviewed and approved the technical contents of CFMI 
CFM56-3/-3B/-3C Service Bulletin (SB) No. 72-877, Revision 1, dated 
June 15, 1998, that describes procedures for identification of affected 
engines by ESN, and replacement of a suspect starter gearshaft with a 
serviceable part.
    Since an unsafe condition has been identified that is likely to 
exist or develop on other engines of the same type design, this AD is 
being issued to prevent a dual inflight engine shutdown. This AD 
requires, within 350 hours time in service (TIS) after the effective 
date of this AD, or by October 1, 1998, whichever occurs first, on 
aircraft with two affected engines installed, removal of one affected 
engine from an aircraft, and replacement with a serviceable engine, or 
replacement of a suspect starter gearshaft with a serviceable part. 
This AD also requires, within 2,100 hours TIS after the effective date 
of this AD, or by February 1, 1999, whichever occurs first, on aircraft 
with only one affected engine installed, removal of the affected engine 
from the aircraft, and replacement with a serviceable engine, or 
removal of the suspect starter gearshaft and replacement with a 
serviceable part. The calendar end-dates were determined based upon 
risk analysis and parts availability. In addition, this AD requires 
reporting to the FAA if the ESN listed in Table 1 of the SB does not 
directly correspond to the adjoining starter gear shaft serial number 
in order to verify that all affected parts have been removed from 
service. The actions are required to be accomplished in accordance with 
the SB 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 98-ANE-44-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:

98-19-10  CFM International: Amendment 39-10752 Docket 98-ANE-44-AD.

    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. 72-877, Revision 1, dated June 15, 1998. These 
engines are installed on but not limited to Boeing 737 series 
aircraft.

    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 (d) 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 an accessory gearbox (AGB) starter gearshaft failure, 
which can result in an inflight engine shutdown, and on aircraft 
with two affected engines installed, possible dual inflight engine 
shutdown and forced landing, accomplish the following:
    (a) On aircraft with two affected engines installed, remove one 
affected engine from the aircraft, and replace with a serviceable 
engine not identified by ESN in Table 1 of CFMI CFM56-3/-3B/-3C SB 
No. 72-877, Revision 1, dated June 15, 1998, or replace the suspect 
starter gearshaft on one of the engines with a serviceable 
gearshaft, in accordance with the Accomplishment Instructions of 
CFMI CFM56-3/-3B/-3C SB No. 72-877, Revision 1, dated June 15, 1998; 
within 350 hours time in service (TIS) after the effective date of 
this AD, or by October 1, 1998, whichever occurs first. Thereafter, 
for the remaining engine, replace suspect starter gearshafts in 
accordance with paragraph (b) of this AD.
    (b) On aircraft with only one affected engine installed, remove 
the affected engine

[[Page 48575]]

from the aircraft, and replace with a serviceable engine not 
identified by ESN in Table 1 of CFMI CFM56-3/-3B/-3C SB No. 72-877, 
Revision 1, dated June 15, 1998, or replace the suspect starter 
gearshaft with a serviceable gearshaft, in accordance with the 
Accomplishment Instructions of CFMI CFM56-3/-3B/-3C SB No. 72-877, 
Revision 1, dated June 15, 1998; within 2,100 hours TIS after the 
effective date of this AD, or by February 1, 1999, whichever occurs 
first.
    (c) Report within 5 working days of replacement of the starter 
gearshaft to the FAA if the ESN listed in Table 1 of CFMI CFM56-3/-
3B/-3C SB No. 72-877, Revision 1, dated June 15, 1998, does not 
directly correspond to the adjoining starter gear shaft serial 
number to verify that all affected parts have been removed from 
service. Report to the Manager, Engine Certification Office, FAA, 
Engine and Propeller Directorate, 12 New England Executive Park, 
Burlington, MA 01803-5299; Fax (781) 238-7199. Reporting 
requirements have been approved by the Office of Management and 
Budget and assigned OMB control number 2120-0056.
    (d) 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, Engine Certification Office. 
Operators shall submit their requests 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.

    (e) 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 aircraft to a location where 
the requirements of this AD can be accomplished.
    (f) The actions required by this AD shall be done in accordance 
with the following CFMI CFM56-3/-3B/-3C SB:

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        Document No.           Pages    Revision            Date        
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72-877......................     1-49           1  June 15, 1998.       
  Total pages:..............      49.                                   
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    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.
    (g) This amendment becomes effective on September 28, 1998.

    Issued in Burlington, Massachusetts, on September 2, 1998.
David A. Downey,
Assistant Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.
[FR Doc. 98-24183 Filed 9-10-98; 8:45 am]
BILLING CODE 4910-13-U