2013-13797. Airworthiness Directives; Bell Helicopter Textron, Inc. (Bell), Model Helicopters

AGENCY:

Federal Aviation Administration, DOT.

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

This document proposes to supersede an existing airworthiness directive (AD) for the Bell Model 412, 412CF, and 412EP helicopters. The AD currently requires reidentifying each affected part-numbered main rotor yoke (yoke) on its data plate, reducing the retirement life of the reidentified yoke, and revising the Airworthiness Limitations section of the maintenance manual or the Instructions for Continued Airworthiness (ICAs) accordingly. Since we issued the AD, we have discovered that the affected yokes do not have a data plate, making compliance with the part-marking requirements of the existing AD impossible. This proposed AD would retain the current requirements with the exception of the P/N marking location. The actions specified in this AD are intended to prevent fatigue cracking of a yoke, failure of the yoke, and subsequent loss of control of the helicopter.

DATES:

We must receive comments on this proposed AD by August 12, 2013.

ADDRESSES:

You may send comments by any of the following methods:

• Federal eRulemaking Docket: Go to http://www.regulations.gov. Follow the online instructions for sending your comments electronically.
• Fax: [phone].
• Mail: Send comments to the U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue SE., Washington, DC 20590-0001.
• Hand Delivery: Deliver to the “Mail” address between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays.

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 economic evaluation, any comments received and other information. The street address for the Docket Operations Office (telephone [phone]) is in the ADDRESSES section. Comments will be available in the AD docket shortly after receipt.

For service information identified in this proposed AD, contact Bell Helicopter Textron, Inc., P.O. Box 482, Fort Worth, TX 76101; telephone [phone]; fax [phone]; or at http://www.bellcustomer.com/​files/​. You may review service information at the FAA, Office of the Regional Counsel, Southwest Region, 2601 Meacham Blvd., Room 663, Fort Worth, Texas 76137.

FOR FURTHER INFORMATION CONTACT:

Michael Kohner, ASW-170, Aviation Safety Engineer, Rotorcraft Directorate, Rotorcraft Certification Office, 2601 Meacham Blvd., Fort Worth, Texas 76137, telephone [phone], fax [phone], email [e-mail].

SUPPLEMENTARY INFORMATION:

Comments Invited

We invite you to participate in this rulemaking by submitting written comments, data, or views. We also invite comments relating to the economic, environmental, energy, or federalism impacts that might result from adopting the proposals in this document. The most helpful comments reference a specific portion of the proposal, explain the reason for any recommended change, and include supporting data. To ensure the docket does not contain duplicate comments, commenters should send only one copy of written comments, or if comments are filed electronically, commenters should submit only one time.

We will file in the docket all comments that we receive, as well as a report summarizing each substantive public contact with FAA personnel concerning this proposed rulemaking. Before acting on this proposal, we will consider all comments we receive on or before the closing date for comments. We will consider comments filed after the comment period has closed if it is possible to do so without incurring expense or delay. We may change this proposal in light of the comments we receive.

Discussion

On February 12, 2009, we issued AD 2009-05-09, Amendment 39-15833 (74 FR 11001, March 16, 2009), for Bell Model 412, 412CF, and 412EP helicopters. The AD requires reidentifying each affected part-numbered yoke based on whether it was ever installed on a Model 412CF helicopter or on a Model 412 or 412EP helicopter with a slope landing kit. The AD also requires reducing the retirement life of each reidentified yoke from 5,000 hours time-in-service (TIS) to 4,500 hours TIS and revising the Airworthiness Limitations section of the maintenance manual or ICAs accordingly. Finally, the AD requires recording each reidentified yoke P/N and the reduced retirement life on the component history card or equivalent record. The AD was prompted by a fatigue analysis that shows that the retirement life should be reduced on certain yokes. Those actions are intended to prevent fatigue cracking of a yoke, failure of the yoke, and subsequent loss of control of the helicopter.

Actions Since Existing AD Was Issued

Since we issued AD 2009-05-09 (74 FR 11001, March 16, 2009), we have discovered that the affected yokes do not have a data plate, making compliance with the part-marking requirements of the existing AD impossible. Bell determined the new P/N should be etched on the side of the yoke rather than on the data plate and issued Revision A to Alert Service Bulletin (ASB) No. 412-08-128 for the Bell Model 412 and 412EP helicopters (ASB 412-08-128A) and ASB No. 412CF-08-35 for the Bell Model 412CF helicopters (ASB 412CF-08-35A), both dated April 14, 2009. Bell also determined the etched surface on the side of the yoke would need to be treated with a chemical film and refinished after reidentifying the P/N to protect the yoke from corrosion.

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 helicopters of these same type designs.

Related Service Information

ASB 412-08-128A and ASB 412CF-08-35A contain procedures for reidentifying the yoke by using a vibrating stylus to etch a new P/N on the side of the yoke. These ASBs also specify recording the new P/N on the component history card and reducing the retirement life of the yoke.

Proposed AD Requirements

This proposed AD would retain the current requirements of AD 2009-05-09 (74 FR 11001, March 16, 2009), with the exception of the P/N marking location. This proposed AD would require that the new P/N be etched on the side of the yoke instead of on the data plate as required by AD 2009-05-09. This action would also require treating the etched surface on the side of yoke with a chemical film and refinishing the yoke after reidentifying the P/N.

Costs of Compliance

We estimate that this proposed AD would affect 115 helicopters of U.S. Registry. We estimate that operators may incur the following costs in order to comply with this AD. It would take about 3 work hours to review and revise the records to reflect the new retirement life and reidentify the P/N at an average labor rate of $85 per work hour. Based on these estimates, the cost would be $255 per helicopter and $29,325 for the U.S. operator fleet. Replacing a yoke would take about 20 work hours and $50,196 for the required parts for a cost of $51,896 per helicopter.

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, 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 to the extent that it justifies making a regulatory distinction; 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.

We prepared an economic evaluation of the estimated costs to comply with this proposed AD and placed it in the AD docket.

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 removing airworthiness directive (AD) 2009-05-09, Amendment 39-15833 (74 FR 11001, March 16, 2009), and adding the following new AD:

Bell Helicopter Textron, Inc.: Docket No. FAA-2013-0500; Directorate Identifier 2012-SW-45-AD.

(a) Applicability

This AD applies to Model 412 and 412EP helicopters with a main rotor yoke assembly (yoke), part number (P/N) 412-010-101-123, -127, -129, or -133, installed; and Model 412CF helicopters with a yoke, P/N 412-010-101-127 or -129, installed; certificated in any category.

(b) Unsafe Condition

This AD defines the unsafe condition as fatigue cracking of a yoke, failure of the yoke, and subsequent loss of control of the helicopter.

(c) Affected ADs

This AD supersedes AD 2009-05-09, Amendment 39-15833 (74 FR 11001, March 16, 2009).

(d) Compliance

You are responsible for performing each action required by this AD within the specified compliance time, unless it has been accomplished previously.

(e) Required Actions

Within 10 hours time-in-service (TIS):

(1) Review the helicopter records to determine all of the helicopter models on which an affected yoke has been installed since its production and the hours TIS of each affected yoke.

(2) If an affected part-numbered yoke is installed or has ever been installed on a Model 412CF helicopter or on a Model 412 or 412EP helicopter with a (BHT-412-SI-62) slope landing kit, P/N 412-704-012-101, installed, do the following:

(i) Reidentify the P/N on the side of the yoke by using a vibrating stylus and etching two lines through the last three digits of the existing P/N and etching “137FM” adjacent to where you etched through the last three digits of the original P/N. This converts each affected yoke P/N to a new yoke P/N 412-010-101-137FM. The serial number remains the same.

Note 1 to paragraph (e)(2)(i) of this AD:

The “FM” P/N suffix denotes a field-modified part.

(ii) Treat the etched surface with chemical film, and apply primer and paint.

(iii) Record the reidentified P/N on the applicable component history card or equivalent record.

(3) If you cannot determine all the model helicopters on which an affected yoke has been installed since its production or whether it has ever been installed on a Model 412 or 412EP helicopter with a (BHT-412-SI-62) slope landing kit, P/N 412-704-012-101, installed, perform the actions required by paragraphs (e)(2)(i) through (e)(2)(iii) of this AD.

(4) For each reidentified yoke, P/N 412-010-101-137FM, reduce the retirement life from 5,000 hours TIS to 4,500 hours TIS. Record the revised life limit on the applicable component history card or equivalent record.

(5) Revise the Airworthiness Limitations section of the applicable maintenance manual or the Instructions for Continued Airworthiness by reducing the retirement life from 5,000 hours TIS to 4,500 hours TIS for each reidentified yoke, P/N 412-010-101-137FM.

(f) Special Flight Permit

Special flight permits will not be issued.

(g) Alternative Methods of Compliance (AMOCs)

(1) The Manager, Rotorcraft Certification Office, FAA, may approve AMOCs for this AD. Send your proposal to: Michael Kohner, ASW-170, Aviation Safety Engineer, 2601 Meacham Blvd., Fort Worth, Texas 76137; telephone [phone], fax [phone]; email [e-mail].

(2) For operations conducted under 14 CFR Part 119 operating certificate or under 14 CFR Part 91, subpart K, we suggest that you notify your principal inspector, or lacking a principal inspector, the manager of the local flight standards district office or certificate holding district office before operating any aircraft complying with this AD through an AMOC.

(h) Additional Information

Bell Helicopter Textron, Inc. Alert Service Bulletins No. 412-08-128 and No. 412CF-08-35, both Revision A and both dated April 14, 2009, which are not incorporated by reference, contain additional information about the subject of this AD. For service information identified in this AD, contact Bell Helicopter Textron, Inc., P.O. Box 482, Fort Worth, TX 76101; telephone [phone]; fax [phone]; or at http://www.bellcustomer.com/​files/​. You may review service information at the FAA, Office of the Regional Counsel, Southwest Region, 2601 Meacham Blvd., Room 663, Fort Worth, Texas 76137.

(i) Subject

Joint Aircraft System/Component (JASC) Code: 6220 Main Rotor Head.

Issued in Fort Worth, Texas, on June 3, 2013.

Kim Smith,

Directorate Manager, Rotorcraft Directorate, Aircraft Certification Service.