Airworthiness Directives; Dowty Propellers Constant Speed Propellers

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Final rule.

SUMMARY:

We are adopting a new airworthiness directive (AD) for certain Dowty Propellers R352/6-123-F/1, R352/6-123-F/2, and R410/6-123-F/35 model propellers. This AD was prompted by reports of dowel hole cracks in the face of the rear hub half. This AD requires installing dowel hole liners as necessary. We are issuing this AD to prevent loss of structural integrity of the propeller hub, which could result in damage to the propeller and damage to the airplane.

DATES:

This AD becomes effective April 15, 2016.

The Director of the Federal Register approved the incorporation by reference of a certain publication listed in this AD as of April 15, 2016.

ADDRESSES:

For service information identified in this final rule, contact Dowty Propellers, 114 Powers Court, Sterling, VA 20166; phone: 703-421-4434; fax: 703-450-0087; email: technicalsupport@dowty.com; Internet: http://dowty.com/services/repair-and-overhaul. You may view this service information at the FAA, Engine & Propeller Directorate, 1200 District Avenue, Burlington, MA 01803. For information on the availability of this material at the FAA, call 781-238-7125. It is also available on the Internet at http://www.regulations.gov by searching for and locating Docket No. FAA-2015-3661.

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-2015-3661; 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 AD, the mandatory continuing airworthiness information (MCAI), the regulatory evaluation, any comments received, and other information. The address for the Docket Office (phone: 800-647-5527) is Document Management Facility, U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue SE., Washington, DC 20590.

FOR FURTHER INFORMATION CONTACT:

Michael Schwetz, Aerospace Engineer, Boston Aircraft Certification Office, FAA, Engine & Propeller Directorate, 1200 District Avenue, Burlington, MA 01803; phone: 781-238-7761; fax: 781-238-7898; email: michael.schwetz@faa.gov.

SUPPLEMENTARY INFORMATION:

Discussion

We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 by adding an AD that would apply to the specified products. The NPRM was published in the Federal Register on October 13, 2015 (80 FR 61330). The NPRM proposed to correct an unsafe condition for the specified products. The MCAI states:

Cracking around the hub location dowel holes in the face of the rear hub half has occurred sporadically. Previous investigations found no manufacturing defects in cracked hubs and concluded that the hub cracking was caused by damage to the dowel holes during propeller installation.

Since that original SB was issued, three hubs have been found to show cracking around the location dowel holes. The hubs were all found cracked within a short period of time and all had low time since new.

This condition, if not detected, can adversely affect the structural integrity of the propeller hub, with possible damage to the propeller and to the aeroplane.

You may obtain further information by examining the MCAI in the AD docket on the Internet at http://www.regulations.gov by searching for and locating Docket No. FAA-2015-3661.

Comments

We gave the public the opportunity to participate in developing this AD. We received no comments on the NPRM (80 FR 61330, October 13, 2015).

However, we changed paragraph (e) Actions and Compliance to revise the compliance times to read, “(1) At the next removal of the propeller from the airplane, after the effective date of this AD, install liners into the hub location dowel holes and identify the hub P/N.

(2) Use Dowty Propellers Alert Service Bulletin (ASB) No. F50-61-A165, Revision 2, dated July 28, 2015 to install the liners and identify the hub.”

We removed Component Maintenance Manual (CMM) 61-10-34, Repair No. 53, dated May 15, 2013, from the Other Related Service Information paragraph of this AD.

We removed Component Maintenance Manual (CMM) 61-10-34, Repair No. 53, dated May 15, 2013, which relates to repair scheme 650510057, from the Credit for Previous Actions paragraph (f)(2) of this AD.

We removed CMM 61-10-34, Repair No. 53, dated May 15, 2013, from the Related Information paragraph (h) of this AD.

Conclusion

We reviewed the available data and determined that air safety and the public interest require adopting this AD with the changes described previously. We determined that these changes will not increase the economic burden on any operator or increase the scope of this AD.

Related Service Information Under 1 CFR Part 51

Dowty Propellers has issued (ASB) No. F50-61-A165, Revision 2, dated July 28, 2015. The service information describes procedures for installing liners in the hub location dowel holes in the face of the rear hub half and identifying the hub with the repair number. 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 of this final rule.

Costs of Compliance

We estimate that this AD affects 4 propellers installed on airplanes of U.S. registry. We also estimate that it will take about 5 hours per propeller to comply with this AD. The average labor rate is $85 per hour. Required parts cost about $322 per propeller. Based on these figures, we estimate the cost of this AD on U.S. operators to be $2,988.

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 levels of government.

For the reasons discussed above, I certify this AD:

(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.

List of Subjects in 14 CFR Part 39

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

Adoption of the Amendment

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

2016-05-04 Dowty Propellers: Amendment 39-18422; Docket No. FAA-2015-3661; Directorate Identifier 2015-NE-24-AD.

(a) Effective Date

This AD becomes effective April 15, 2016.

(b) Affected ADs

None.

(c) Applicability

This AD applies to Dowty Propellers R352/6-123-F/1, R352/6-123-F/2, and R410/6-123-F/35 model propellers, part numbers (P/Ns) 660715001, 660715004, and 660715005 with hub P/Ns 660715201, 660715255, 660720217, 660720241, 660720252, 660720260, and 660720288, installed.

(d) Reason

This AD was prompted by reports of dowel hole cracks in the face of the rear hub half. We are issuing this AD to prevent loss of structural integrity of the propeller hub, which could result in damage to the propeller and damage to the airplane.

(e) Actions and Compliance

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

(1) At the next removal of the propeller from the airplane, after the effective date of this AD, install liners into the hub location dowel holes and identify the hub P/N.

(2) Use Dowty Propellers Alert Service Bulletin (ASB) No. F50-61-A165, Revision 2, dated July 28, 2015 to install the liners and identify the hub.

(f) Credit for Previous Actions

You may take credit for the actions required by paragraph (e) of this AD if you performed those actions before the effective date of this AD using Dowty Propellers ASB No. F50-61-A165, Revision 1, dated May 12, 2015; or initial issue, dated November 19, 2012.

(g) Alternative Methods of Compliance (AMOCs)

The Manager, Boston Aircraft Certification Office, FAA, may approve AMOCs for this AD. Use the procedures found in 14 CFR 39.19 to make your request.

(h) Related Information

(1) For more information about this AD, contact Michael Schwetz, Aerospace Engineer, Boston Aircraft Certification Office, FAA, 1200 District Avenue, Burlington, MA 01803; phone: 781-238-7761; fax: 781-238-7898; email: michael.schwetz@faa.gov.

(2) Refer to MCAI European Aviation Safety Agency AD 2015-0158, dated July 30, 2015, for more information. You may examine the MCAI in the AD docket on the Internet at http://www.regulations.gov by searching for and locating it in Docket No. FAA-2015-3661.

(i) 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.

(i) Dowty Propellers Alert Service Bulletin No. F50-61-A165, Revision 2, dated July 28, 2015.

(ii) Reserved.

(3) For Dowty Propellers service information identified in this AD, contact Dowty Propellers, 114 Powers Court, Sterling, VA 20166; phone: 703-421-4434; fax: 703-450-0087; email: technicalsupport@dowty.com; Internet: http://dowty.com/services/repair-and-overhaul.

(4) You may view this service information at FAA, Engine & Propeller Directorate, 1200 District Avenue, Burlington, MA. For information on the availability of this material at the FAA, call 781-238-7125.

(5) You may view this service information 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.