Airworthiness Directives; Sikorsky Aircraft Corporation Helicopters

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

We propose to adopt a new airworthiness directive (AD) for Sikorsky Aircraft Corporation (Sikorsky) Model S-92A helicopters. This proposed AD would require altering the fire bottle inertia switch wiring and performing a cartridge functional test of the fire extinguishing system. This proposed AD is prompted by the inadvertent tripping of inertia-switches that has led to unintentional discharging of the fire bottles, leaving the helicopter's auxiliary power unit and engines without fire protection. The proposed actions are intended to prevent unintentional and undetected fire bottle discharges and subsequent unavailability of fire suppression in case of a fire.

DATES:

We must receive comments on this proposed AD by July 12, 2016.

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: 202-493-2251.
• 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 by searching for and locating Docket No. FAA-2016-6640; 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 800-647-5527) is in the ADDRESSES section. Comments will be available in the AD docket shortly after receipt.

For service information identified in this proposed rule, 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 the referenced service information at the FAA, Office of the Regional Counsel, Southwest Region, 10101 Hillwood Pkwy, Room 6N-321, Fort Worth, TX 76177.

FOR FURTHER INFORMATION CONTACT:

Kris Greer, Aviation Safety Engineer, Boston Aircraft Certification Office, Engine & Propeller Directorate, 1200 District Avenue, Burlington, Massachusetts 01803; telephone (781) 238-7799; email kristopher.greer@faa.gov.

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

We propose to adopt a new AD for certain serial-numbered Sikorsky Model S-92A helicopters. Sikorsky has informed us that the inadvertent tripping of inertia switches has caused several engine and auxiliary power unit fire bottle discharges during taxi, flight, and landing operations. Because these discharges are undetected, the fire bottles remain unavailable in the event of a fire.

This proposed AD would require altering the fire bottle inertia switch wiring to disable the automatic feature of the fire extinguishing system. This proposed AD would also require performing a cartridge functional test. The proposed actions are intended to prevent an unintentional and undetected fire bottle discharge and subsequent unavailability of fire suppression in the event of a fire.

FAA's Determination

We are proposing this AD because we evaluated all known relevant information and determined that an unsafe condition exists and is likely to exist or develop on other products of the same type design.

Related Service Information Under 1 CFR Part 51

We reviewed Sikorsky Alert Service Bulletin 92-26-005A, Revision A, dated June 27, 2014 (ASB 92-26-005A). ASB 92-26-005A specifies performing a one-time alteration of the fire bottle inertia switch wiring to disable the automatic actuation feature of the fire extinguishing system. ASB 92-26-005A includes figures that depict the wiring and electrical connector pin changes.

This service information is reasonably available because the interested parties have access to it through their normal course of business or by the means identified in the ADDRESSES section.

Other Related Service Information

We also reviewed Sikorsky Alert Service Bulletin 92-26-005, Basic Issue, dated June 18, 2014 (ASB 92-26-005). ASB 92-26-005 contains the same procedures as ASB 92-26-005A. However, ASB 92-26-005A contains an additional figure.

Proposed AD Requirements

This proposed AD would require, within 90 days, altering the fire bottle inertia switch wiring to disable the automatic discharge of fire bottles and performing a post-alteration cartridge functional test.

Differences Between This Proposed AD and the Service Information

This proposed AD has a compliance date within 90 days, and the service information has a calendar date, which has already passed. This proposed AD does not require performing a cartridge functional test prior to alteration. The service information does specify performing a cartridge functional test prior to alteration.

Costs of Compliance

We estimate that this proposed AD would affect 80 helicopters of U.S. Registry. Labor costs are estimated at $85 per work-hour. Altering the fire bottle switch and performing a cartridge functional test would take about 2 work-hours. No parts would be needed for an estimated cost of $170 per helicopter and $13,600 for the U.S. fleet.

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.

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

Sikorsky Aircraft Corporation: Docket No. FAA-2016-6640; Directorate Identifier 2015-SW-084-AD.

(a) Applicability

This AD applies to Model S-92A helicopters, serial number 920006 through 920250, certificated in any category.

(b) Unsafe Condition

This AD defines the unsafe condition as inadvertent tripping of a fire bottle inertia-switch. This condition results in an unintentional and undetected fire bottle discharge and subsequent unavailability of fire suppression in the event of a fire.

(c) Comments Due Date

We must receive comments by July 12, 2016.

(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 90 days:

(1) Alter each fire bottle inertia switch by following the Accomplishment Instructions, paragraph 3.B., of Sikorsky Alert Service Bulletin 92-26-005A, Revision A, dated June 27, 2014.

(2) Perform a cartridge functional test.

(f) Credit for Actions Previously Completed

Compliance with Sikorsky Alert Service Bulletin ASB 92-26-005, Basic Issue, dated June 18, 2014, before the effective date of this AD is considered acceptable for compliance with the actions specified in paragraph (e) of this AD.

(g) Alternative Methods of Compliance (AMOC)

(1) The Manager, Boston Aircraft Certification Office, FAA, may approve AMOCs for this AD. Send your proposal to: Kris Greer, Aviation Safety Engineer, Boston Aircraft Certification Office, Engine & Propeller Directorate,1200 District Avenue, Burlington, Massachusetts 01803; telephone (781) 238-7799; email kristopher.greer@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.

(h) Additional Information

Sikorsky Alert Service Bulletin 92-26-005, Basic Issue, dated June 18, 2014, which is not incorporated by reference, contains additional information about the subject of this proposed rule. For service information identified in this proposed rule, 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 information at the FAA, Office of the Regional Counsel, Southwest Region, 10101 Hillwood Pkwy, Room 6N-321, Fort Worth, TX 76177.

(i) Subject

Joint Aircraft Service Component (JASC) Code: 2621 Fire Bottle, Fixed.