Airworthiness Directives; CFM International CFM56 Series Turbofan Engines

AGENCY:

Federal Aviation Administration, DOT.

ACTION:

Final rule; request for comments.

SUMMARY:

This amendment adopts a new airworthiness directive (AD) that is applicable to CFM International (CFMI) CFM56-5C4/1 series turbofan engines. This action requires that the LPT conical support, P/N 337-002-407-0, installed in CFM56-5C4/1 engines, be removed from service at or before reaching the cyclic life limit of 9,350 cycles-since-new (CSN). This amendment is prompted by the discovery of an error in the Time Limits Section of Chapter 5 of the CFM56-5C Engine Shop Manual. The manual incorrectly lists the published cyclic life limit of the CFMI CFM56-5C4/1 LPT conical support, (P/N) 337-002-407-0, as 15,000 CSN, rather than the certified value of 9,350 CSN. The actions specified in this AD are intended to prevent LPT conical supports from remaining in service beyond their certified cyclic life limit, which could result in an uncontained engine failure and damage to the airplane.

DATES:

Effective September 7, 2001.

Comments for inclusion in the Rules Docket must be received on or before October 22, 2001.

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-15-AD, 12 New England Executive Park, Burlington, MA 01803-5299. Comments may also be sent via the Internet using the following address: “9-ane-adcomment@faa.gov”. Comments sent via the Internet must contain the docket number in the subject line.

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) 238-7133; fax (781) 238-7199.

SUPPLEMENTARY INFORMATION:

The FAA has been informed by CFMI that the cyclic life limit of the CFM56-5C4/1 Low Pressure Turbine (LPT) conical support, P/N 337-002-407-0, published in the Time Limits Section of Chapter 5 of the CFM56-5C Engine Shop Manual is incorrect, and will be corrected at the next revision to the manual. The incorrect published cyclic life reads 15,000 cycles since new (CSN) instead of the certified value of 9,350 CSN. This condition, if not corrected, could result in the LPT conical support remaining in service beyond its certified cyclic life limit, which could result in an uncontained engine failure and damage to the airplane. Currently, the CFMI fleet has not incorporated LPT Conical Support, P/N 337-002-407-0, into any of the CFM56-5C4/1 engines. Therefore, this AD will not result in any economic impact on the U.S. operators. However, as the operators convert CMF56-5C engines into different model configurations, there is a potential that LPT Conical Support, P/N 337-002-407-0, will be installed in the CFM56-5C4/1 engine model.

FAA's Determination of An Unsafe Condition and Proposed Actions

Although this affected engine model is not used on any airplanes that are registered in the United States, the possibility exists this engine model could be used on airplanes that are registered in the United States in the future. This AD reestablishes the certified cyclic life limit for LPT conical support P/N 337-002-407-0, by requiring the replacement of LPT conical support P/N 337-002-407-0, at or before accumulating 9,350 CSN. This AD is being issued to prevent LPT conical supports from remaining in service beyond their certified cyclic life limit, which could result in an uncontained engine failure and damage to the airplane.

Immediate Adoption of This AD

Since there are no domestic operators of this engine model, notice and opportunity for prior public comment are unnecessary. Therefore, a situation exists that allows the immediate adoption of this regulation.

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 action must submit a self-addressed, stamped postcard on which the following statement is made: “Comments to Docket Number 2001-NE-15-AD.” The postcard will be date stamped and returned to the commenter.

Regulatory Impact

This final 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 final rule.

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
• 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.

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

2001-17-14 CFM International: Amendment 39-12405. Docket 2001-NE-15-AD.

Applicability

This airworthiness directive (AD) is applicable to CFM International (CFMI) CFM56-5C4/1 series turbofan engines with low pressure turbine (LPT) conical support, part number (P/N) 337-002-407-0, installed. These engines are installed on, but not limited to Airbus Industrie A320 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 (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

Compliance with this AD is required as indicated.

To prevent an LPT conical support from remaining in service beyond its certified cyclic life limit, which could result in an uncontained engine failure and damage to the airplane, accomplish the following:

(a) Remove LPT conical support, P/N 337-002-407-0, at or before accumulating 9,350 cycles-since-new (CSN) and replace with a serviceable part.

(b) After the effective date of this AD, do not install any LPT conical support, P/N 337-002-407-0 with 9,350 CSN or greater, into CFM56-5C4/1 model engines.

(c) This AD reestablishes the certified cyclic life limit for LPT conical support, P/N 337-002-407-0, which was published incorrectly in the Time Limits Section of Chapter 5 of the CFM56-5C Engine Shop Manual. This Manual will be revised to correct this error. Thereafter, except as provided in paragraph (d) of this AD, no alternative cyclic retirement life limits may be approved for LPT conical support, P/N 337-002-407-0.

Alternative Methods of Compliance

(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 (ECO). Operators must submit their requests 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.

Effective Date of This AD

(e) This amendment becomes effective on September 7, 2001.