[Federal Register Volume 68, Number 95 (Friday, May 16, 2003)]
[Proposed Rules]
[Pages 26553-26555]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 03-12241]


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

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2002-NE-26-AD]
RIN 2120-AA64


Airworthiness Directives; CFM International, S.A. CFM56-2C, -3 
Series, and -5 Series Turbofan Engines

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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

SUMMARY: The Federal Aviation Administration (FAA) proposes to adopt a 
new airworthiness directive (AD) that is applicable to CFM 
International, S.A. CFM56-2C, -3, and -5 series turbofan engines. This 
proposal would require removing from service main fuel pumps with 
bronze bearings and installing main fuel pumps with aluminum/bronze 
alloy bearings. This proposal is prompted by several reports of 
indications of wear and failures of main fuel pump bronze bearings. The 
actions specified by the proposed AD are intended to prevent failures 
of main fuel pump bearings, resulting in fuel filter clogging, fuel 
flow degradation, fuel manifold and nozzle clogging resulting in 
diminished in-flight restart capability, low pressure turbine (LPT) 
case burn-through, inability to obtain a successful engine start, and 
damage to the airplane.

DATES: Comments must be received by July 15, 2003.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), New England Region, Office of the Regional 
Counsel, Attention: Rules Docket No. 2002-NE-26-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.

FOR FURTHER INFORMATION CONTACT: Glorianne Niebuhr, 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:

[[Page 26554]]

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 2002-NE-26-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. 2002-NE-26-AD, 12 New England Executive 
Park, Burlington, MA 01803-5299.

Discussion

    The FAA has become aware that since the introduction of main fuel 
pump bronze bearings into service on CFM56-2C, -3, and -5 series 
turbofan engines, wear of the backside of the bearings into the main 
fuel bearing plate has been observed. This can lead to fuel filter 
clogging, fuel flow degradation, fuel manifold and nozzle clogging 
resulting in diminished in-flight restart capability, LPT case burn-
through, inability to obtain a successful engine start, and damage to 
the airplane. The main fuel pump manufacturer has determined that this 
wear is caused by the low coefficient of friction between the bronze 
bearings and the aluminum bearing plate which allowed relative movement 
of the bearing during operation. The main fuel pump manufacturer has 
shown that main fuel pumps with aluminum/bronze alloy bearings have a 
high coefficient of friction between the bearing and the aluminum 
bearing plate minimizing relative movement of the bearings and reducing 
wear. Use of main fuel pumps with aluminum/bronze alloy bearings 
decreases the risk of bearing failure which could lead to fuel filter 
clogging, fuel flow degradation, fuel manifold and nozzle clogging 
resulting in diminished in-flight restart capability, LPT case burn-
through, inability to obtain a successful engine start, and damage to 
the airplane.

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 CFM International, S.A. CFM56-2C, -3 series, 
and -5 series turbofan engines of the same type design, the proposed AD 
would require removal from service of certain part number main fuel 
pumps and installation of serviceable main fuel pumps. The actions 
would be required to be done at the next engine removal, engine module 
removal, or main fuel pump removal after the effective date of this AD, 
whichever is earlier, but no later than January 1, 2007.

Economic Analysis

    There are approximately 6,048 CFM56-2C, -3 series, and -5 series 
turbofan engines of the affected design in the worldwide fleet. The FAA 
estimates that 2,249 engines installed on airplanes of U.S. registry 
would be affected by this proposed AD. A replacement fuel pump would 
cost approximately $74,000. Using average shop visitation rates, 562 
engines are expected to be affected per year. Based on these figures, 
the total cost to replace fuel pumps for U.S. operators is estimated to 
be $41,588,000 per year.

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:

CFM International, S.A.: Docket No. 2002-NE-26-AD.

    Applicability: This airworthiness directive (AD) is applicable 
to CFM International, S.A. CFM56-2C, -3, and -5 series turbofan 
engines. These engines are installed on, but not limited to Airbus 
Industrie A319, A320, Boeing 737, and McDonnell Douglas DC-8 
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 (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 at the next 
engine removal, engine module removal, or main fuel pump removal 
after the effective date of this AD, whichever is earlier, but no 
later than January 1, 2007, unless already done.
    To prevent failures of main fuel pump bearings, resulting in 
fuel filter clogging, fuel flow degradation, fuel manifold and 
nozzle

[[Page 26555]]

clogging resulting in diminished in-flight restart capability, low 
pressure turbine (LPT) case burn-through, inability to obtain a 
successful engine start, and damage to the airplane, do the 
following:

Main Fuel Pumps Installed on CFM56-2C Engines

    (a) For CFM56-2C engines, do the following:
    (1) Remove from service main fuel pumps part number (P/N) 301-
779-002-0.
    (2) For all CFM56-2C series engines that have incorporated CFM 
International (CFMI) Service Bulletin (SB) (CFM56-2C) 73-081, remove 
from service main fuel pumps P/N 301-776-101-0, P/N 301-776-102-0, 
P/N 301-776-103-0, P/N 301-776-104-0, P/N 301-776-105-0, P/N 301-
776-106-0, P/N 301-776-108-0, P/N 301-776-109-0, P/N 301-776-110-0, 
P/N 301-776-111-0, P/N 301-776-112-0, P/N 301-776-113-0, P/N 301-
778-801-0, P/N 301-778-802-0, P/N 301-778-804-0, and P/N 301-778-
805-0.
    (3) For all CFM56-2C engines that have incorporated CFMI SB 
(CFM56-2C) 73-078, remove from service main fuel pumps P/N 301-779-
006-0.
    (4) Install a serviceable main fuel pump. Information on 
converting removed pumps into serviceable pumps can be found in CFMI 
SB (CFM56-2C) 73-0104, Revision 2, dated July 27, 2000.

Main Fuel Pumps Installed on CFM56-3 Series Engines

    (b) For CFM56-3 series engines, do the following:
    (1) Remove main fuel pumps P/N 301-779-002-0.
    (2) For all CFM56-3 series engines that have incorporated CFMI 
SB (CFM56-3) 73-082, remove from service main fuel pumps P/N 301-
779-006-0.
    (3) For all CFM56-3 series engines that have incorporated CFMI 
SB (CFM56-3) 73-087, remove from service main fuel pumps P/N 301-
778-801-0, P/N 301-778-802-0, P/N 301-778-804-0, and P/N 301-778-
805-0.
    (4) Install a serviceable main fuel pump. Information on 
converting removed pumps into serviceable pumps can be found in CFMI 
SB (CFM56-3) 73-0120, Revision 4, dated July 27, 2000.

Main Fuel Pumps Installed on CFM56-5 Series Engines

    (c) For CFM56-5 series engines, do the following:
    (1) Remove main fuel pumps P/N 301-785-502-0.
    (2) For all CFM56-5 series engines that have incorporated CFMI 
SB (CFM56-5A) 73-077, remove from service main fuel pumps P/N 301-
785-504-0.
    (3) Install a serviceable main fuel pump. Information on 
converting removed pumps into serviceable pumps can be found in CFMI 
SB (CFM56-5A) 73-0126, Revision 3, dated September 25, 2000.

Do Not Install Main Fuel Pumps

    (d) After the effective date of this AD, do not install the 
following P/N main fuel pumps onto any engine:
    (1) For all engines: (P/N) 301-779-002-0, P/N 301-779-006-0, P/N 
301-785-502-0, and P/N 301-785-504-0.
    (2) For CFM56-2C engines that have incorporated SB CFMI (CFM56-
2C) 73-081 but have not incorporated SB CFMI SB (CFM56-2C) 73-0104: 
P/N 301-776-101-0, P/N 301-776-102-0, P/N 301-776-103-0, P/N 301-
776-104-0, P/N 301-776-105-0, P/N 301-776-106-0, P/N 301-776-108-0, 
P/N 301-776-109-0, P/N 301-776-110-0, P/N 301-776-111-0, P/N 301-
776-112-0, P/N 301-776-113-0, P/N 301-778-801-0, P/N 301-778-802-0, 
P/N 301-778-804-0, P/N 301-778-805-0.
    (3) For CFM56-3 series engines that have incorporated SB CFMI 
(CFM56-3) 73-087 but have not incorporated CFMI SB (CFM56-3) 73-
0120: P/N 301-778-801-0, P/N 301-778-802-0, P/N 301-778-804-0, and 
P/N 301-778-805-0.

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

    (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 May 12, 2003.
Francis A. Favara,
Acting Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.
[FR Doc. 03-12241 Filed 5-15-03; 8:45 am]
BILLING CODE 4910-13-P