E9-30219. Airworthiness Directives; CFM International, S.A. CFM56-5B1/P, -5B2/P, -5B3/P, -5B3/P1, -5B4/P, -5B5/P, -5B6/P, -5B7/P, -5B8/P, -5B9/P, -5B1/2P, -5B2/2P, -5B3/2P, -5B3/2P1, -5B4/2P, -5B4/P1, -5B6/2P, -5B4/2P1, and -5B9/2P Turbofan Engines

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

The FAA proposes to supersede an existing airworthiness directive (AD) for CFM International, S.A. CFM56-5B series turbofan engines. That AD currently requires reviewing exhaust gas temperature (EGT) monitoring records to determine EGT margin deterioration, and for airplanes where both engines have greater than 80 °centigrade (C) of EGT margin deterioration, borescope-inspecting the high-pressure compressor (HPC) of both engines. That AD also currently requires removing from service any engine that does not pass the borescope inspection and, if both engines pass, removing and replacing one of the engines with an engine that has 80 °C or less of EGT margin deterioration. That AD also currently requires continuous monitoring of EGT margin deterioration on engines in service to prevent two engines on an airplane from having greater than 80 °C of EGT margin deterioration. This proposed AD would require continuous monitoring of EGT margin deterioration, removing FADEC software version 5.B.Q and earlier versions from the engine as mandatory terminating action to the repetitive recalculating and EGT monitoring for certain engine models, and removing other certain engine models from service if the EGT margin deterioration is greater than 75 °C. This proposed AD results from the need to reduce the affected engine models listed in AD 2009-01-01 from 25 to 19, the need to reduce the engine EGT margin deterioration removal threshold from greater than 80 °C to greater than 75 °C, the need to mandate a terminating action to the repetitive recalculating and EGT monitoring for certain engines, and the need to remove certain engines from service if the EGT margin deterioration is greater than 75 °C. We are proposing this AD to prevent HPC stalls, which could prevent continued safe flight or landing.

DATES:

We must receive any comments on this proposed AD by February 19, 2010.

ADDRESSES:

Use one of the following addresses to comment on this proposed AD.

• Federal eRulemaking Portal: Go to http://www.regulations.gov and follow the instructions for sending your comments electronically.
• Mail: Docket Management Facility, U.S. Department of Transportation, 1200 New Jersey Avenue, SE., West Building Ground Floor, Room W12-140, Washington, DC 20590-0001.
• Hand Delivery: Deliver to Mail address above between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays.
• Fax: [phone].

FOR FURTHER INFORMATION CONTACT:

James Rosa, Aerospace Engineer, Engine Certification Office, FAA, Engine and Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803; e-mail: [e-mail]; telephone [phone]; fax [phone].

SUPPLEMENTARY INFORMATION:

Comments Invited

We invite you to send any written relevant data, views, or arguments regarding this proposal. Send your comments to an address listed under ADDRESSES. Include “Docket No. FAA-2008-1353; Directorate Identifier 2008-NE-46-AD” in the subject line of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of the proposed AD. We will consider all comments received by the closing date and may amend the proposed AD in light of those comments.

We will post all comments we receive, without change, to http://www.regulations.gov, including any personal information you provide. We will also post a report summarizing each substantive verbal contact with FAA personnel concerning this proposed AD. Using the search function of the Web site, anyone can find and read the comments in any of our dockets, including, if provided, the name of the individual who sent the comment (or signed the comment on behalf of an association, business, labor union, etc.). You may review the DOT's complete Privacy Act Statement in the Federal Register published on April 11, 2000 (65 FR 19477-78).

Examining the AD Docket

You may examine the AD docket on the Internet at http://www.regulations.gov; or in person at the Docket Operations office between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD docket contains this proposed AD, the regulatory evaluation, any comments received, and other information. The street address for the Docket Operations office (telephone [phone]) is the same as the Mail address provided in the ADDRESSES section. Comments will be available in the AD docket shortly after receipt.

Discussion

The FAA proposes to amend 14 CFR part 39 by superseding AD 2009-01-01, Amendment 39-15779 (73 FR 80296, December 31, 2008). That AD requires reviewing EGT monitoring records to determine EGT margin deterioration, and, for airplanes where both engines have greater than 80 °C of EGT margin deterioration, borescope-inspecting the HPC of both engines. That AD also currently requires removing from service any engine that does not pass the borescope inspection, and if both engines pass, removing and replacing one of the engines with an engine that has 80 °C or less EGT margin deterioration. That AD also currently requires continuous monitoring of EGT margin deterioration on engines in service, to prevent two engines on an airplane from having greater than 80 °C of EGT margin deterioration. That AD was the result of an Airbus A321 airplane powered by CFM56-5B1/P turbofan engines with severe HPC deterioration, that stalled during climb out after takeoff. That condition, if not corrected, could result in HPC stalls, which could prevent continued safe flight or landing.

Actions Since AD 2009-01-01 Was Issued

Since AD 2009-01-01 was issued, we determined that engine models CFM56-5B1, -5B2, -5B4, -5B5, -5B6, and -5B7, which were listed in that AD, are not affected by the unsafe condition. Also, CFM International, S.A. has released a FADEC software version that addresses the HPC stall problem for certain engine models. We also determined that we need to reduce the engine EGT margin deterioration removal threshold from greater than 80 °C to greater than 75 °C. Reducing this removal threshold will provide additional margin to assure that an engine stall will not occur. Also, we have determined the need to require a mandatory terminating action to the repetitive EGT monitoring required by that AD and this proposed AD, for CFM56-5B1/P, -5B2/P, -5B3/P, -5B3/P1, -5B4/P, -5B5/P, -5B6/P, -5B7/P, -5B8/P, -5B9/P, and -5B4/P1 turbofan engines. Also, we have determined the need to remove CFM56-5B1/2P, -5B2/2P, -5B3/2P, -5B3/2P1, -5B4/2P, -5B4/2P1, -5B6/2P and -5B9/2P turbofan engines from service if the EGT margin deterioration is greater than 75 °C.

FAA's Determination and Requirements of the Proposed AD

We have evaluated all pertinent information and identified an unsafe condition that is likely to exist or develop on other products of this same type design. For that reason, we are proposing this AD, for CFM International, S.A. CFM56-5B1/P, -5B2/P, -5B3/P, -5B3/P1, -5B4/P, -5B4/P1, -5B5/P, -5B6/P, -5B7/P, -5B8/P, and -5B9/P turbofan engines with FADEC software version 5.B.Q. or any earlier version installed, to require the following:

• On the effective date of this proposed AD, and at any time after the effective date of the proposed AD, you are to monitor and calculate EGT margin deterioration; and
• As mandatory terminating action to the repetitive recalculating and monitoring of EGT margin deterioration, you are to remove FADEC software version 5.B.Q and earlier versions from certain engines that have greater than 75 °C of EGT margin deterioration within 150 additional cycles-in-service (CIS); and
• As mandatory terminating action to the repetitive recalculating and monitoring of EGT margin deterioration, you are to remove FADEC software version 5.B.Q and earlier versions from certain engines that have less than or equal to 75 °C of EGT margin deterioration within 900 additional CIS.

We are also proposing this AD, for CFM International, S.A. CFM56-5B1/2P, -5B2/2P, -5B3/2P, -5B3/2P1, -5B4/2P, -5B4/2P1, -5B6/2P, and -5B9/2P turbofan engines to require the following:

• On the effective date of this proposed AD, and at any time after the effective date of this proposed AD, you are to monitor and calculate EGT margin deterioration; and
• You are to remove engines from service that have greater than 75 °C of EGT margin deterioration within 150 additional CIS.

We are also proposing this AD to remove engine models CFM56-5B1, -5B2, -5B4, -5B5, -5B6, and -5B7 from the applicability.

Costs of Compliance

We estimate that this proposed AD would affect 397 engines installed on airplanes of U.S. registry. We also estimate that it would take about one work-hour to install FADEC software. The average labor rate is $80 per work-hour. There are no required parts costs. Based on these figures, we estimate the total cost of the proposed AD to U.S. operators to be $31,760.

Interim Actions

These actions are interim actions and we anticipate further rulemaking actions in the future, including further action to address the remaining engines in service that are above 75 °C of EGT margin deterioration.

Authority for This Rulemaking

Title 49 of the United States Code specifies the FAA's authority to issue rules on aviation safety. Subtitle I, Section 106, describes the authority of the FAA Administrator. Subtitle VII, Aviation Programs, describes in more detail the scope of the Agency's authority.

We are issuing this rulemaking under the authority described in Subtitle VII, Part A, Subpart III, Section 44701, “General requirements.” Under that section, Congress charges the FAA with promoting safe flight of civil aircraft in air commerce by prescribing regulations for practices, methods, and procedures the Administrator finds necessary for safety in air commerce. This regulation is within the scope of that authority because it addresses an unsafe condition that is likely to exist or develop on products identified in this rulemaking action.

Regulatory Findings

We have determined that this proposed AD would not have federalism implications under Executive Order 13132. This proposed AD 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.

For the reasons discussed above, I certify that the proposed AD:

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. Would not have a significant economic impact, positive or negative, on a substantial number of small entities under the criteria of the Regulatory Flexibility Act.

We prepared a regulatory evaluation of the estimated costs to comply with this proposed AD. See the ADDRESSES section for a location to examine the regulatory evaluation.

List of Subjects in 14 CFR Part 39

• Air transportation
• Aircraft
• Aviation safety
• Safety

The Proposed Amendment

Under the authority delegated to me by the Administrator, the Federal Aviation Administration proposes to amend 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.

§ 39.13

[Amended]

2. The FAA amends § 39.13 by removing Amendment 39-15779 (73 FR 80296, December 31, 2008) and by adding a new airworthiness directive to read as follows:

CFM International, S.A.: Docket No. FAA-2008-1353; Directorate Identifier 2008-NE-46-AD.

Comments Due Date

(a) The Federal Aviation Administration (FAA) must receive comments on this airworthiness directive (AD) action by February 19, 2010.

Affected ADs

(b) This AD supersedes AD 2009-01-01, Amendment 39-15779.

Applicability

(c) This AD applies to CFM International, S.A. CFM56-5B1/P, -5B2/P, -5B3/P, -5B3/P1, -5B4/P, -5B5/P, -5B6/P, -5B7/P, -5B8/P, -5B9/P, -5B1/2P, -5B2/2P, -5B3/2P, -5B3/2P1, -5B4/2P, -5B4/P1, -5B6/2P, -5B4/2P1, and -5B9/2P turbofan engines. These engines are installed on, but not limited to, Airbus A318, A319, A320, and A321 series airplanes.

Unsafe Condition

(d) This AD results from the need to reduce the affected engine models listed in AD 2009-01-01 from 25 to 19, the need to reduce the engine EGT margin deterioration removal threshold from greater than 80 °C to greater than 75 °C, the need to mandate a terminating action to the repetitive recalculating and EGT monitoring for certain engines, and the need to remove certain engines from service if the EGT margin deterioration is greater than 75 °C. We are issuing this AD to prevent high-pressure compressor stalls, which could prevent continued safe flight or landing.

Compliance

(e) You are responsible for having the actions required by this AD performed within the compliance times specified unless the actions have already been done.

(f) On the effective date of this AD, and at any time after the effective date of this AD, for CFM International, S.A. CFM56-5B1/P, -5B2/P, -5B3/P, -5B3/P1, -5B4/P, -5B4/P1, -5B5/P, -5B6/P, -5B7/P, -5B8/P and -5B9/P turbofan engines:

(1) Monitor and calculate engine EGT margin deterioration. Guidance on calculating EGT margin deterioration can be found in CFM International, S.A. Alert Service Bulletin no. CFM56-5B S/B 72-A0722, Revision 1, dated March 20, 2009.

(2) As mandatory terminating action to the repetitive recalculating and monitoring of EGT margin deterioration, remove FADEC software version 5.B.Q and earlier versions from engines that have greater than 75 °C of EGT margin deterioration within 150 additional cycles-in-service (CIS).

(3) As mandatory terminating action to the repetitive recalculating and monitoring of EGT margin deterioration, remove FADEC software version 5.B.Q and earlier versions from engines that have less than or equal to 75 °C of EGT margin deterioration within 900 additional CIS.

(g) On the effective date of this AD, and at any time after the effective date of this AD, for CFM International, S.A. CFM56-5B1/2P, -5B2/2P, -5B3/2P, -5B3/2P1, -5B4/2P, -5B4/2P1, -5B6/2P and -5B9/2P turbofan engines:

(1) Monitor and calculate engine EGT margin deterioration.

(2) Remove engines from service that have greater than 75 °C of EGT margin deterioration within 150 additional CIS. Do not install an engine that has greater than 75 °C of EGT margin deterioration.

Installation Prohibition

(h) After the effective date of this AD, do not install FADEC software version 5.B.Q or any earlier software versions to any of the engines affected by this AD.

Interim Actions

(i) These actions are interim actions and we anticipate further rulemaking actions in the future, including further action to address the remaining engines in service that are above 75 °C deterioration of EGT margin.

Alternative Methods of Compliance (AMOCs)

(j) The Manager, Engine Certification Office, FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19.

Related Information

(k) Refer to European Aviation Safety Agency Airworthiness Directive 2009-0088, Revision 1, dated April 28, 2009, CFM International, S.A. Service Bulletin No. CFM56-5B S/B 73-0229, Revision 1, dated February 26, 2009, and CFM International, S. A. Service Bulletin No. CFM56-5B S/B 72-0722, Revision 1, dated March 20, 2009, for related information.

(l) Contact CFM International, S.A., Technical Customer Support, 1 Neumann Way, Cincinnati, OH 45215; telephone [phone]; fax [phone], for a copy of the service information referenced in this AD.

(m) Contact James Rosa, Aerospace Engineer, Engine Certification Office, FAA, Engine and Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803; e-mail: [e-mail]; telephone [phone]; fax [phone], for more information about this AD.

Issued in Burlington, Massachusetts on December 10, 2009.

Peter A. White,

Assistant Manager, Engine and Propeller Directorate, Aircraft Certification Service.