AD 2015-19-51

We are publishing a new airworthiness directive (AD) for Sikorsky Aircraft Corporation Model S-76A, S-76B, S-76C, and S-76D helicopters, which was sent previously to all known U.S. owners and operators of these helicopters. This AD requires inspecting the main rotor (M/R) and tail rotor (T/R) pushrod assemblies and the jamnuts, and applying slippage marks across the pushrod tubes and jamnuts. This AD is prompted by an accident of a Sikorsky Aircraft Corporation Model S-76C helicopter. During preliminary investigation, a failed pushrod assembly was identified. These actions are intended to prevent loss of M/R or T/R flight control and subsequent loss of control of the helicopter.

Final rule; request for comments.

Adoption of the Amendment

Accordingly, under the authority delegated to me by the Administrator,

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the FAA amends 14 CFR part 39 as follows:

PART 39--AIRWORTHINESS DIRECTIVES

0 1. The authority citation for part 39 continues to read as follows:

Authority: 49 U.S.C. 106(g), 40113, 44701.

Sec. 39.13 [Amended]

0 2. The FAA amends Sec. 39.13 by adding the following new airworthiness directive (AD):

2015-19-51 Sikorsky Aircraft Corporation: Amendment 39-18300; Docket No. FAA-2015-3940; Directorate Identifier 2015-SW-065-AD.

(a) Applicability

This AD applies to Model S-76A, S-76B, S-76C, and S-76D helicopters with main rotor (M/R) servo input control pushrod (pushrod) assembly part number (P/N) 76400-00034-059 or tail rotor (T/R) pushrod assembly P/N 76400-00014-071 installed, certificated in any category.

(b) Unsafe Condition

This AD defines the unsafe condition as a loose jamnut. This condition could result in failure of a pushrod assembly, loss of M/R or T/R flight control, and subsequent loss of control of the helicopter.

(c) Effective Date

This AD becomes effective November 10, 2015 to all persons except those persons to whom it was made immediately effective by Emergency AD 2015-19-51, issued on September 14, 2015, which contains the requirements of this AD.

(d) Compliance

You are responsible for performing each action required by this AD within the specified compliance time unless it has already been accomplished prior to that time.

(e) Required Actions

Within five hours time-in-service:
(1) Inspect each pushrod end to determine whether a 0.020 inch diameter lockwire can pass through the inspection hole.
(i) If the lockwire passes through the inspection hole, replace the pushrod assembly.
(ii) If the lockwire does not pass through the inspection hole, inspect the jamnut to determine whether it is seated against the pushrod and whether itcan be turned with finger pressure. If the jamnut is not seated against the pushrod or can be turned with finger pressure, replace the pushrod assembly.
(2) Apply two slippage marks across each pushrod tube and jamnut as follows:
(i) Clean the area where a slippage mark is to be applied.
(ii) Apply two slippage marks across the pushrod tube and jamnut, parallel and on opposite sides of each other. Each slippage mark must extend at least 0.5 inch onto the pushrod tube and must not cover the inspection hole. Figures 2 and 4 of Sikorsky Alert Service Bulletin No. 76-67-57, Basic Issue, dated September 10, 2015, illustrate slippage marks across a pushrod tube and jamnut.

(f) Alternative Methods of Compliance (AMOCs)

(1) The Manager, Boston Aircraft Certification Office, FAA, may approve AMOCs for this AD. Send your proposal to: Blaine Williams, Aerospace Engineer, Boston Aircraft Certification Office, Engine & Propeller Directorate, 12 New England Executive Park, Burlington, Massachusetts 01803; telephone (781) 238-7161; email blaine.williams@faa.gov.
(2) For operations conducted under a 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.

(g) Additional Information

Sikorsky Alert Service Bulletin No. 76-67-57, Basic Issue, dated September 10, 2015, which is not incorporated by reference, contains additional information about the subject of this AD. For service information identified in this AD, contact Sikorsky Aircraft Corporation, Customer Service Engineering, 124 Quarry Road, Trumbull, CT 06611; telephone 1-800-Winged-S or 203-416-4299; email sikorskywcs@sikorsky.com. You may review a copy of the service information at the FAA, Office of the Regional Counsel, Southwest Region, 10101 Hillwood Pkwy, Room 6N-321, Fort Worth, TX 76177.

(h) Subject

Joint Aircraft Service Component (JASC) Code: 2700, Flight Control System.

Comments Invited

This AD is a final rule that involves requirements affecting flight safety, and we did not provide you with notice and an opportunity to provide your comments prior to it becoming effective. However, 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 resulted from adopting this AD. The most helpful comments reference a specific portion of the AD, 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

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submit them 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 concerningthis rulemaking during the comment period. We will consider all the comments we receive and may conduct additional rulemaking based on those comments.

Discussion

On September 14, 2015, we issued Emergency AD 2015-19-51 for Sikorsky Aircraft Corporation Model S-76A, S-76B, S-76C, and S-76D helicopters with M/R servo input control pushrod (pushrod) assembly part number (P/N) 76400-00034-059 or T/R pushrod assembly P/N 76400- 00014-071 installed. Emergency AD 2015-19-51 requires inspecting the M/ R forward, aft, and lateral pushrod assemblies, the T/R pushrod assembly, and the jamnuts, and applying slippage marks across the pushrod tubes and jamnuts. Emergency AD 2015-19-51 was sent previously to all known U.S. owners and operators of these helicopters and was prompted by an accident of a Sikorsky Aircraft Corporation Model S-76C helicopter in which a failed pushrod assembly was identified during preliminary investigation. Separation of the pushrod tube and the control rod endwith bearing was found.

FAA's Determination

We are issuing this AD because we evaluated all the relevant information and determined the unsafe condition described previously is likely to exist or develop on other helicopters of these same type designs.

Related Service Information

Sikorsky issued Alert Service Bulletin No. 76-67-57, Basic Issue, dated September 10, 2015 (ASB), which specifies a one-time inspection of the M/R forward, aft, and lateral pushrod assemblies, the T/R pushrod assembly, and the jamnuts for proper installation, condition, and security. If a pushrod or jamnut does not meet criteria specified in the inspection, the ASB specifies replacing the assembly. The ASB also specifies applying two slippage marks across each M/R and T/R pushrod tube and jamnut. Further, the ASB references the applicable maintenance manual for a new recurring inspection of the slippage marks.

AD Requirements

This AD requires, within five hours time-in-service(TIS), inspecting each M/R and T/R pushrod assembly by inspecting the position of the control rod end in the pushrod tube. If the lockwire passes through the inspection hole, this AD requires replacing the pushrod assembly. If the lockwire does not pass through the inspection hole, this AD requires inspecting the jamnut to determine seating position against the pushrod and whether the jamnut can be turned with finger pressure. If the jamnut is not seated against the pushrod or is loose, this AD requires replacing the pushrod assembly. This AD also requires, both for those pushrod assemblies that are replaced and for those that pass the inspections, applying two slippage marks across each M/R and T/R pushrod tube and jamnut.

Interim Action

We consider this AD to be an interim action as the accident investigation is ongoing. If additional action is later identified, we might consider further rulemaking.

Costs of Compliance

We estimate that this AD affects 198 helicopters of U.S. Registry. We estimate that operators may incur the following costs in order to comply with this AD at an average labor rate of $85 per work-hour. It takes about 1 work-hour to inspect the pushrod assemblies and jamnut for a cost of $85 per helicopter and $16,830 for the U.S. fleet. It takes a minimal amount of time to apply the slippage marks for a negligible cost. Replacing a pushrod assembly takes about 1.5 work- hours for a labor cost of $128. Parts for an M/R pushrod assembly cost $2,411 for a total replacement cost of $2,539. Parts for a T/R pushrod assembly cost $1,905 for a total replacement cost of $2,033.

FAA's Justification and Determination of the Effective Date

Providing an opportunity for public comments prior to adopting these AD requirements would delay implementing the safety actions needed to correct this known unsafe condition. Therefore, we found and continue to find that the risk to the flying public justifies waiving notice and comment prior to the adoption of this rule because the previously described unsafe condition can adversely affect the controllability of the helicopter and the initial required action must be accomplished within five hours TIS.
Since it was found that immediate corrective action was required, notice and opportunity for prior public comment before issuing this AD were impracticable and contrary to public interest and good cause existed to make the AD effective immediately by Emergency AD 2015-19- 51, issued on September 14, 2015, to all known U.S. owners and operators of these helicopters. These conditions still exist and the AD is hereby published in the Federal Register as an amendment to section 39.13 of the Federal Aviation Regulations (14 CFR 39.13) to make it effective to all persons.

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 AD will not have federalism implications under Executive Order 13132. This AD will 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 levelsof government.
For the reasons discussed, I certify that this AD:
1. Is not a ``significant regulatory action'' under Executive Order 12866;
2. Is not a ``significant rule'' under 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 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.