E8-22522. Airworthiness Directives; Honeywell International Inc. LTS101 Series Turboshaft and LTP101 Series Turboprop 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. LTS101 series turboshaft and LTP101 series turboprop engines with certain gas generator turbine discs installed. This proposed AD would require reducing the life limits for certain gas generator turbine discs. This proposed AD results from an error in a change to the engineering drawing for the gas generator turbine disc from which they manufactured 260 discs. We are proposing this AD to prevent rupture of the gas generator turbine disc, which could result in uncontained engine failure and damage to the aircraft.

DATES:

We must receive any comments on this proposed AD by November 24, 2008.

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., P.O. Box 52181, Phoenix, AZ 85072-2181, U.S.A.; telephone [phone] (U.S.A.) or [phone] (International); 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-2008-1019; Directorate Identifier 2007-NE-49-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

Honeywell International Inc. has informed us that they manufactured 260 gas generator turbine discs to an erroneous drawing change. Because of this, the gas generator turbine disc could rupture before reaching its published life limit. This condition, if not corrected, could result in uncontained engine failure and damage to the aircraft.

Relevant Service Information

We have reviewed and approved the technical contents of Honeywell International Inc. Service Bulletin (SB) LT 101-71-00-0002, Revision 25, dated August 31, 2007, that describes a reduced life limit and drawdown schedules for certain gas generator turbine discs and lists the serial numbers of those discs.

Differences Between the Proposed AD and the Manufacturer's Service Information

Although the SB applies to all LTS101 turboshaft engines and LTP101 turboprop engines, this proposed AD would not apply to models LTS101-700D-2 and LTS101-850B-2 turboshaft engines because the affected discs are not eligible for installation on those engine models. We also revised the drawdown schedules in Table 1 of this proposed AD to make the grace periods consistent.

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 removing any disc, part number (P/N) 4-111-015-14 that has a serial number (SN) listed in Appendix 1 of SB LT 101-71-00-0002, Revision 25, dated August 31, 2007, using the drawdown schedules specified in Table 1 of this proposed AD.

The proposed AD would require you to use the service information described previously to perform these actions.

Costs of Compliance

We estimate that this proposed AD would affect 260 engines installed on aircraft of U.S. registry. We also estimate that it would take 1.0 work-hour per engine to perform the proposed actions, and that the average labor rate is $80 per work-hour. Required parts would cost about $8,000 per engine. Based on these figures, we estimate the total cost of the proposed AD to U.S. operators to be $2,100,800.

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, Textron Lycoming, and Avco Lycoming): Docket No. FAA-2008-1019; Directorate Identifier 2007-NE-49-AD.

Comments Due Date

(a) The Federal Aviation Administration (FAA) must receive comments on this airworthiness directive (AD) action by November 24, 2008.

Affected ADs

(b) None.

Applicability

(c) This AD applies to Honeywell International Inc. models LTS101-600A-2, -600A-3, -600A-3A, -650B-1, -650B-1A, -650C-2, -650C-3, -650C-3A, -750A-1, -750A-3, -750B-1, -750B-2, and -750C-1 turboshaft engines and LTP101-600A-1A and -700A-1A turboprop engines with certain gas generator turbine discs, part number (P/N) 4-111-015-14, installed. These engines are installed on, but not limited to, Eurocopter France AS350, Eurocopter Deutchland GMBH BK117, and Bell Helicopter Textron 222 helicopters; and Page Thrush, Air Tractor AT-302, Industrie Aeronautiche e Meccaniche (formerly Piaggio & Co.) P166-DL3, Pacific Aero 08-600, and Riley International R421 airplanes.

Unsafe Condition

(d) This AD results from an error in a change to the engineering drawing for the gas generator turbine disc from which they manufactured 260 discs. We are issuing this AD to prevent rupture of the gas generator turbine disc, which could result in uncontained engine failure and damage to the aircraft.

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.

Drawdown Schedule and New Reduced Life Limit for Certain Gas Generator Turbine Discs

(f) For model LTS101-600A-3 and -750 series turboshaft engines and model LTP101-600A-1A and -700A-1A turboprop engines that have a gas generator turbine disc serial number (SN) specified in Appendix 1 of Honeywell International Inc. Service Bulletin (SB) LT 101-71-00-0002, Revision 25, dated August 31, 2007; remove the engine using the drawdown schedule specified in Table 1 of this AD.

Table 1—Drawdown Schedule

Engine model	If disc cycle count on the effective date of this AD is—	Then remove disc—
(1) LTS101-600A-3 and -750 series turboshaft engines	(i) Fewer than 4,940 cycles-since-new (CSN)	Before accumulating 5,040 CSN.
	(ii) 4,940 or more CSN	Within 100 cycles-in-service (CIS) or 4 months, whichever occurs earlier.
(2) LTP101-600A-1A and -700A-1A turboprop engines	(i) Fewer than 2,720 CSN	Before accumulating 2,770 CSN.
	(ii) 2,720 or more CSN	Within 50 CIS or 4 months after the effective date of this AD, whichever occurs earlier.

Installation Prohibitions

(g) After the effective date of this AD, don't install any model LTS101-600A-3 or -750 series turboshaft engine that has a gas generator turbine disc, P/N 4-111-015-14, with a SN listed in Appendix 1 of Honeywell International Inc. SB LT 101-71-00-0002, Revision 25, dated August 31, 2007; if that disc has 5,040 or more CSN.

(h) After the effective date of this AD, don't install any model LTP101-600A-1A or -700A-1A turboprop engine that has a gas generator turbine disc, P/N 4-111-015-14, with a SN listed in Appendix 1 of Honeywell International Inc. SB LT 101-71-00-0002, Revision 25, dated August 31, 2007; if that disc has 2,770 or more CSN.

Alternative Methods of Compliance

(i) 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

(j) Honeywell International Inc. Service Bulletin LT 101-71-00-0002, Revision 25, dated August 31, 2007, pertains to the subject of this AD.

(k) 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 September 19, 2008.

Francis A. Favara,

Manager, Engine and Propeller Directorate, Aircraft Certification Service.