2011-20170. Airworthiness Directives; Honeywell International Inc. TPE331-10 and TPE331-11 Series Turboprop Engines

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

We propose to adopt a new airworthiness directive (AD) for the products listed above. This proposed AD would require inspecting certain serial number (S/N) first stage turbine disks, part number (P/N) 3101520-1 and P/N 3107079-1. This proposed AD was prompted by a report of an uncontained failure of a first stage turbine disk that had a metallurgical defect. We are proposing this AD to prevent uncontained failure of the first stage turbine disk and damage to the airplane.

DATES:

We must receive comments on this proposed AD by September 23, 2011.

ADDRESSES:

You may send comments by any of the following methods:

• Federal eRulemaking Portal: Go to http://www.regulations.gov. Follow the instructions for submitting comments.
• Fax: [phone].
• Mail: U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue, SE., Washington, DC 20590.
• Hand Delivery: Deliver to Mail address above between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays.

For service information identified in this proposed AD, contact Honeywell International Inc., 111 S. 34th Street, Phoenix, AZ 85034-2802; Web site: http://portal.honeywell.com;​; or call Honeywell toll free at [phone] (U.S./Canada) or [phone] (International Direct). You may review copies of the referenced service information at the FAA, Engine & Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803. For information on the availability of this material at the FAA, call [phone].

Examining the AD Docket

You may examine the AD docket on the Internet at http://www.regulations.gov;​; or in person at the Docket Management Facility 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 Office (phone: [phone]) is in the ADDRESSES section. Comments will be available in the AD docket shortly after receipt.

FOR FURTHER INFORMATION CONTACT:

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

SUPPLEMENTARY INFORMATION:

Comments Invited

We invite you to send any written relevant data, views, or arguments about this proposal. Send your comments to an address listed under the ADDRESSES section. Include “Docket No. FAA-2011-0789; Directorate Identifier 2011-NE-04-AD” at the beginning of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of this proposed AD. We will consider all comments received by the closing date and may amend this proposed AD because 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 we receive about this proposed AD.

Discussion

In May 2008, we received a report of an uncontained separation of a first stage turbine disk, P/N 3107079-1. The disk was installed in a TPE331-11U turboprop engine. That disk, which has a 20,000-cycle life, failed after accumulating 8,314 cycles-in-service. The fracture revealed a large melt-related oxide cluster inclusion in the web area of the disk, which occurred during the forging alloy melting process. The disk was produced from Waspaloy material, from Heat Lot 9-7121, which was melted by Special Metals in 1980. We have determined that approximately 360 turbine disks were produced from the same heat lot as the failed forged turbine disk and therefore may have similar inclusions. This condition, if not corrected, could result in uncontained failure of the first stage turbine disks made from these billets and damage to the airplane.

Relevant Service Information

We reviewed Honeywell International Inc. Alert Service Bulletin (ASB) TPE331-72-A2156, dated December 2, 2008. The Honeywell ASB TPE331-72-A2156, dated December 2, 2008, provides S/Ns of the affected turbine disks and describes procedures for initial and repetitive fluorescent penetrant inspection (FPI) and eddy current inspection (ECI) of the first stage turbine disk.

FAA's Determination

We are proposing this AD because we evaluated all the relevant information and determined the unsafe condition described previously is likely to exist or develop in other products of the same type design.

Proposed AD Requirements

This proposed AD would require:

• For turbine disks that have an S/N listed in Table 1 of this proposed AD with 4,100 or fewer cycles-since-new (CSN) on the effective date of this proposed AD, performing an initial FPI and ECI within 4,500 CSN or at the next access, whichever occurs first.
• For turbine disks that have an S/N listed in Table 1 of this proposed AD with more than 4,100 CSN on the effective date of this proposed AD, performing an initial FPI and ECI within 400 cycles-in-service after the effective date of this proposed AD or at the next access, whichever occurs first.
• Thereafter, for turbine disks that have an S/N listed in Table 1 of this proposed AD, perform a repetitive FPI and ECI at each scheduled hot section inspection, but not to exceed 3,600 hours-since-last inspection.

The proposed AD would require that you do these actions using the service information described previously.

Costs of Compliance

We estimate that this proposed AD would affect 90 engines installed on airplanes of U.S. registry. We also estimate that it would take about 20 work-hours per engine to perform the proposed actions, and that the average labor rate is $85 per work-hour. Required parts would cost about $19,000 per engine. We estimate that one disk would fail the initial inspection and that repetitive inspections would be performed on 89 engines. We estimate that one engine would fail the repetitive inspections and that further repetitive inspections would be performed on 88 engines. We estimate that an additional one disk would fail those repetitive inspections before retirement. Based on these figures, we estimate the total cost of the proposed AD to U.S. operators to be $511,155.

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 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 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),

(3) Will not affect intrastate aviation in Alaska, and

(4) 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.

List of Subjects in 14 CFR Part 39

• Air transportation
• Aircraft
• Aviation safety
• Incorporation by reference
• Safety

The Proposed Amendment

Accordingly, under the authority delegated to me by the Administrator, the FAA 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 (AD):

Honeywell International Inc. (Formerly AlliedSignal Inc., Garrett Engine Division; Garrett Turbine Engine Company; and AiResearch Manufacturing Company of Arizona): Docket No. FAA-2011-0789; Directorate Identifier 2011-NE-04-AD.

Comments Due Date

(a) We must receive comments by September 23, 2011.

Affected ADs

(b) None.

Applicability

(c) Honeywell International Inc. TPE331-10, -10AV, -10GP, -10GT, -10N, -10P, -10R, -10T, -10U, -10UA, -10UF, -10UG, -10UGR, -10UR, and TPE331-11U model turboprop engines with a first stage turbine disk, part number (P/N) 3101520-1 or 3107079-1, with a serial number (S/N) listed in Table 2 of Honeywell International Inc. Alert Service Bulletin (ASB) TPE331-72-A2156, dated December 2, 2008, installed.

Unsafe Condition

(d) This AD was prompted by a report of an uncontained failure of a first stage turbine disk that had a metallurgical defect. We are issuing this AD to prevent uncontained failure of the first stage turbine disk and damage to the airplane.

Compliance

(e) Comply with this AD within the compliance times specified, unless already done.

Initial Inspection

(f) For first stage turbine disks, P/N 3101520-1 or 3107079-1, that have an S/N listed in Table 2 of Honeywell International Inc. ASB TPE331-72-A2156, dated December 2, 2008, inspect the disks as follows:

(1) For turbine disks with 4,100 or fewer cycles-since-new (CSN) on the effective date of this proposed AD, perform an initial fluorescent penetrant inspection (FPI) by using paragraph 3.B.(2) through 3.B.(5) of Honeywell International Inc. ASB TPE331-72-A2156, dated December 2, 2008, within 4,500 CSN or at the next access, whichever occurs first.

(2) For turbine disks with more than 4,100 CSN on the effective date of this proposed AD, perform an initial FPI by using paragraph 3.B.(2) through 3.B.(5) of Honeywell International Inc. ASB TPE331-72-A2156, dated December 2, 2008, within 400 cycles-in-service (CIS) after the effective date of this proposed AD or at the next access, whichever occurs first.

(3) If the disk passes the FPI inspection, perform a special eddy current inspection (ECI) by using paragraph 3.B.(6) of Honeywell International Inc. ASB TPE331-72-A2156, dated December 2, 2008, before returning the disk to service.

(g) If you find a crack in the disk, remove the disk from service.

Repetitive Inspection

(h) Thereafter, for first stage turbine disks, P/N 3101520-1 or 3107079-1, that have an S/N listed in Table 2 of Honeywell International Inc. ASB TPE331-72-A2156, dated December 2, 2008, inspect the disks as follows:

(1) Perform a repetitive inspection at each scheduled hot section inspection, but not to exceed 3,600 hours-since-last inspection. Use paragraph 3.B.(2) through 3.B.(5) of Honeywell International Inc. ASB TPE331-72-A2156, dated December 2, 2008.

(2) If the disk passes the FPI inspection, perform a special ECI by using paragraph 3.B.(6) of Honeywell International Inc. ASB TPE331-72-A2156, dated December 2, 2008, before returning the disk to service.

(i) If you find a crack in the disk, remove the disk from service.

Definition

(j) For the purpose of this AD, “next access to the first stage turbine disk” is defined as the removal of the second stage turbine nozzle from the turbine stator housing.

Alternative Methods of Compliance (AMOCs)

(k) The Manager, Los Angles Aircraft 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

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

(m) For service information identified in this AD, contact Honeywell International Inc., 111 S. 34th Street, Phoenix, AZ 85034-2802; Web site: http://portal.honeywell.com;​; or call Honeywell toll free at [phone] (U.S./Canada) or [phone] (International Direct). You may review copies of the referenced service information at the FAA, Engine & Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803. For information on the availability of this material at the FAA, call [phone].

Issued in Burlington, Massachusetts, on August 1, 2011.

Peter A. White,

Acting Manager, Engine & Propeller Directorate, Aircraft Certification Service.