E8-28269. Airworthiness Directives; Honeywell International Inc. ALF502L-2 and ALF502L-2C Turbofan Engines

AGENCY:

Federal Aviation Administration (FAA), Department of Transportation (DOT).

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

The FAA proposes to adopt a new airworthiness directive (AD) for Honeywell International Inc. ALF502L-2 and ALF502L-2C turbofan engines with certain high-pressure compressor (HPC) first stage discs installed. This proposed AD would require performing a dimensional inspection to determine if excessive disc balance material was removed and a magnetic particle inspection if the disc passes the dimensional inspection. This proposed AD results from reports of discs found with excessive material removed from the balancing material of the disc. We are proposing this AD to prevent the discs from fracturing before reaching the currently published life limit. A disc fracture could result in an uncontained failure of the disc and damage to the airplane.

DATES:

We must receive any comments on this proposed AD by January 27, 2009.

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].

You can get the service information identified in this proposed AD from Honeywell International Inc. 111 S. 34th Street, Phoenix, AZ 85034-2802, U.S.A.; telephone [phone], Web site http://portal.honeywell.com/​wps/​portal/​aero.

FOR FURTHER INFORMATION CONTACT:

Robert Baitoo, Aerospace Engineer, Los Angeles Aircraft Certification Office, FAA, Transport Airplane Directorate, 3960 Paramount Blvd., Lakewood, CA 90712-4137; e-mail: [e-mail]; telephone [phone]; fax [phone].

SUPPLEMENTARY INFORMATION:

Comments Invited

We invite you to send us any written relevant data, views, or arguments regarding this proposal. Send your comments to an address listed under ADDRESSES. Include “Docket No. FAA-2008-1207; Directorate Identifier 2007-NE-47-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 HPC first stage disc has an area from which too much material could be removed during the balancing operation. We received reports of two HPC first stage discs with too much material removed from the balance material of the disc. Honeywell revised the engine overhaul manual to clarify the limits for removed balance material. Removing too much material from the balance area of the disc may result in a reduced fatigue life of the disc. This condition, if not corrected, could result in the disc fracturing before reaching its currently published life limit. A disc fracture could result in an uncontained failure of the disc and damage to the airplane.

Relevant Service Information

We have reviewed and approved the technical contents of Honeywell Alert Service Bulletin (ASB) ALF/LF A72-1102, dated April 24, 2007, that describes procedures for inspecting the HPC first stage disc for missing balance material.

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. We are proposing this AD, which would require at the next shop visit, but not later than 2,500 cycles-in-service after the effective date of this proposed AD, inspecting the HPC first stage disc for excessive missing balance material and a magnetic particle inspection.

Costs of Compliance

We estimate that this proposed AD would affect 148 engines installed on airplanes of U.S. registry. We also estimate that it would take about 3 work-hours per engine to perform the proposed actions, and that the average labor rate is $80 per work-hour. Required parts would cost about $21,000 per engine. Based on these figures, we estimate the total cost of the proposed AD to U.S. operators to be $3,143,520.

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. You may get a copy of this summary at the address listed under ADDRESSES.

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 adding the following new airworthiness directive:

Honeywell International Inc. (Formerly AlliedSignal and Lycoming): Docket No. FAA-2008-1207; Directorate Identifier 2007-NE-47-AD.

Comments Due Date

(a) The Federal Aviation Administration (FAA) must receive comments on this airworthiness directive (AD) action by January 27, 2009.

Affected ADs

(b) None.

Applicability

(c) This AD applies to Honeywell International Inc. ALF502L-2 and ALF502L-2C turbofan engines with high pressure compressor (HPC) first stage discs, part numbers (P/Ns) 2-101-331-03, 2-101-331-04, and 2-101-331-10, installed. These engines are installed on, but not limited to, Bombardier CL-600-1A11 airplanes.

Unsafe Condition

(d) This AD results from reports of discs found with excessive material removed from the balancing material of the disc. We are issuing this AD to prevent the discs from fracturing before reaching the currently published life limit. A disc fracture could result in an uncontained failure of the disc and damage to the airplane.

Compliance

(e) You are responsible for having the actions required by this AD performed at the next shop visit, but not later than 2,500 cycles-in-service after the effective date of this AD, unless the actions have already been done.

Visual Inspection

(f) For discs with 5,000 or more cycles-since-new on the effective date of this AD, perform a dimensional inspection of the HPC first stage disc to determine if excessive disc balance material was removed. See the following Figure 1 for limits.

(g) Replace disc if excessive disc balance material was removed. See limits in Figure 1 of this AD.

(h) If removed balance material is acceptable, perform a magnetic particle inspection of the disc rim and slots for cracks using a 3 to 7 power magnification glass. The Engine Overhaul Manual, 72-34-11, Inspection/Check, contains information on the magnetic particle inspection.

(i) Replace disc if you find any cracks.

Alternative Methods of Compliance

(j) The Manager, Los Angeles Aircraft Certification Office, has the authority to approve alternative methods of compliance for this AD if requested using the procedures found in 14 CFR 39.19.

Related Information

(k) Honeywell Alert Service Bulletin ALF/LF A72-1102, dated April 24, 2007, contains information that pertains to the subject of this AD.

(l) Contact Robert Baitoo, Aerospace Engineer, Los Angeles Aircraft Certification Office, FAA, Transport Airplane Directorate, 3960 Paramount Blvd., Lakewood, CA 90712-4137; e-mail: [e-mail]; telephone [phone]; fax [phone], for more information about this AD.

Issued in Burlington, Massachusetts, on November 21, 2008.

Peter A. White,

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