SUPPLEMENTARY INFORMATION:

Discussion

We received reports of a fatal accident on a Piper Aircraft, Inc. Model PA-31T airplane. Although the investigation is not complete, the National Transportation Safety Board (NTSB) found evidence of thermal damage near the main electrical bus circuit breaker panel. The enclosed space also includes hydraulic lines that run directly beneath the panel. The wiring in this area showed evidence of electrical arcing, and the hydraulic lines showed evidence of fire.

During the accident investigation, we and the NTSB examined the area below the circuit breaker panel in 6 different Model PA-31T series airplanes. All 6 airplanes had instances of wiring and hydraulic lines making direct contact and some of the airplanes showed signs of wiring rubbing or chafing adjacent structure or flammable fluid lines.

This condition, if not corrected, could lead to electrical arcing and a possible inflight fire in an area that is not accessible by the crew. We are issuing this AD to correct the unsafe condition on these products.

Related Service Information Under 1 CFR Part 51

We reviewed Piper Aircraft, Inc. Service Bulletin No. 1301, dated January 6, 2017. The service information describes procedures for visually inspecting the area below the main circuit breaker panel and rerouting and replacing wires and/or parts as necessary. 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 .

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 in other products of the same type design.

AD Requirements

This AD requires accomplishing the actions specified in the service information described previously, except as discussed under “Differences Between the AD and the Service Information.”

Differences Between the AD and the Service Information

This AD requires the initial inspection within 30 days after the effective date and repetitive inspections at intervals not to exceed 12 calendar months, which differs from the compliance time specified in the service bulletin. Also, the service bulletin specifies the use of a 10X magnifying glass; however, the inspection space is very confined, and it is difficult to use a magnifying glass in the area. This AD requires the use of mirrors, a suitable light source, and other equipment (small cameras, borescopes, and magnification, etc.,) as needed to do the visual inspection of the area.

The Summary section of the service bulletin states for you to contact your Factory Authorized Service Facility to make arrangements for compliance with the service bulletin. Any appropriately licensed mechanic may do the work of this AD. Please note that to receive any warranty credit from Piper, the work may need to be done at the Factory Authorized Service Facility.

FAA's Justification and Determination of the Effective Date

An unsafe condition exists that requires the immediate adoption of this AD. The FAA has found that the risk to the flying public justifies waiving notice and comment prior to adoption of this rule because rubbing or chafing of the electrical wires to adjacent structure or flammable fluid lines could lead to electrical arcing and possible inflight fire in an area that is not accessible by the crew. Therefore, we find that notice and opportunity for prior public comment are impracticable and that good cause exists for making this amendment effective in less than 30 days.

Comments Invited

This AD is a final rule that involves requirements affecting flight safety and was not preceded by notice and an opportunity for public comment. However, we invite you to send any written data, views, or arguments about this AD. Send your comments to an address listed under the ADDRESSES section. Include the docket number FAA-2017-0045 and Directorate Identifier 2017-CE-002-AD at the beginning of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of this AD. We will consider all comments received by the closing date and may amend this 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 AD.

Costs of Compliance

We estimate that this AD affects 335 airplanes of U.S. registry.

We estimate the following costs to comply with this AD:

We estimate the following costs to do any necessary replacements that would be required based on the results of the inspection. We have no way of determining the number of aircraft that might need these replacements: ( printed page 9500)

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

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 levels of government.

For the reasons discussed above, 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, 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.

Adoption of the Amendment

Accordingly, under the authority delegated to me by the Administrator, the FAA amends 14 CFR part 39 as follows:

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):

2017-02-06 Piper Aircraft, Inc.: Amendment 39-18785; Docket No. FAA-2017-0045; Directorate Identifier 2017-CE-002-AD.

(a) Effective Date

This AD is effective February 22, 2017.

(b) Affected ADs

None.

(c) Applicability

This AD applies to Piper Aircraft, Inc. Models PA-31T, serial numbers (SN) 31T-7400002 through 31T-8120104; PA-31T1, SNs 31T-7804001 through 31T-8304003 and SNs 31T-1104004 through 31T-1104017; PA-31T2, SNs 31T-8166001 through 31T-8166076 and 31T-1166001 through 31T-1166008; PA-31T3, SNs 31T-8275001 through 31T-8475001 and 31T-5575001; and PA-31P-350, SNs 31P-8414001 through 31P-8414050; certificated in any category.

(d) Subject

Joint Aircraft System Component (JASC)/Air Transport Association (ATA) of America Code 2497, Electrical Power/Electrical Power System Wiring.

(e) Unsafe Condition

This AD was prompted by a fatal accident where evidence of thermal damage in the area below the main circuit breaker panel was found. We are issuing this AD to detect and correct rubbing/chafing of wiring with other wires, adjacent structure, and/or flammable fuel lines, which could lead to electrical arcing and possible inflight fire in an area that is not accessible by the crew.

(f) Compliance

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

(g) Inspection

(1) Within 30 days after February 22, 2017 (the effective date of this AD) and repetitively thereafter at intervals not to exceed 12 calendar months, do a detailed visual inspection of the wiring in the area below the main circuit breaker panel using mirrors, a suitable light source, and other equipment (small cameras, borescopes, and magnification, etc.,) as needed to do the visual inspection of the area. Follow paragraphs 1, 2, and 3 of the Instructions section of Piper Aircraft, Inc. Service Bulletin No. 1301, dated January 6, 2017.

Note 1 to paragraph (g)(1) of this AD: You may begin the repetitive inspections before 12 calendar months after the initial inspection to coincide the repetitive inspection with the annual inspection.

(2) If any damage and/or rubbing or chafing is found during any of the inspections required in paragraph (g)(1) of this AD, before further flight, reroute, rework, or replace any wires as specified in paragraphs 2 and 3 of the Instructions section of Piper Aircraft, Inc. Service Bulletin No. 1301, dated January 6, 2017.

(3) Perform a functional test after any inspection required by this AD as specified in paragraph 4 of the Instructions section of Piper Aircraft, Inc. Service Bulletin No. 1301, dated January 6, 2017.

(4) The Summary section of Piper Aircraft, Inc. Service Bulletin No. 1301, dated January 6, 2017, states to contact the Factory Authorized Piper Service Facility to make arrangements for compliance with the service bulletin. Any appropriately licensed mechanic may do the work of this AD. Please note that to receive any warranty credit from Piper, the work may need to be done at the Factory Authorized Service Facility.

(h) Alternative Methods of Compliance (AMOCs)

(1) The Manager, Atlanta Aircraft Certification Office (ACO), FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. In accordance with 14 CFR 39.19, send your request to your principal inspector or local Flight Standards District Office, as appropriate. If sending information directly to the manager of the ACO, send it to the attention of the person identified in paragraph (i) of this AD.

(2) Before using any approved AMOC, notify your appropriate principal inspector, or lacking a principal inspector, the manager of the local flight standards district office/certificate holding district office.

(i) Related Information

For more information about this AD, contact Bryan Long, Aerospace Engineer, FAA, Atlanta Aircraft Certification Office, 1701 Columbia Avenue, College Park, Georgia 30337; phone: (404) 474-5578; fax: (404) 474-5606; email: bryan.long@faa.gov.

(j) Material Incorporated by Reference

(1) The Director of the Federal Register approved the incorporation by reference (IBR) of the service information listed in this paragraph under 5 U.S.C. 552(a) and 1 CFR part 51.

(2) You must use this service information as applicable to do the actions required by this AD, unless the AD specifies otherwise. ( printed page 9501)

(i) Piper Aircraft, Inc. Service Bulletin No. 1301, dated January 6, 2017.

(ii) Reserved.

(3) For service information identified in this AD, contact Piper Aircraft, Inc., Customer Service, 2926 Piper Drive, Vero Beach, Florida 32960; telephone: (877) 879-0275; fax: none; email: customer.service@piper.com; Internet: www.piper.com.

(4) You may view this referenced service information at the FAA, Small Airplane Directorate, 901 Locust, Kansas City, Missouri 64106. For information on the availability of this material at the FAA, call (816) 329-4148.

(5) You may view this service information that is incorporated by reference at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, call 202-741-6030, or go to: http://www.archives.gov/​federal-register/​cfr/​ibr-locations.html.