AD 2008-21-07R1

We are revising airworthiness directive (AD) 2008-21-07 for certain Dowty Propellers model R408/6-123-F/17 propellers. AD 2008-21- 07 required initial and repetitive inspections of the blade bonded metallic leading edge (L/E) guards for correct bonding until they accumulate more than 1,200 flight hours (FH) time-in-service. This AD requires the same inspection and replacement requirements of AD 2008- 21-07. This AD also provides an optional terminating action to those requirements. This AD was prompted by updated service bulletins that identify terminating action to the requirements of AD 2008-21-07. We are issuing this AD to prevent the loss of the bonded metallic L/E guard of the propeller, which could result in damage to the propeller or to the airplane, or injury to personnel.

Final rule.

Adoption of the Amendment

Accordingly, under the authority delegated to me by the Administrator, the FAA amends part 39 of the Federal Aviation Regulations (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 removing airworthiness directive (AD) 2008-21-07, Amendment 39-15691 (73 FR 61346, October 16, 2008), and adding the following new AD:

AD 2008-21-07R1 Dowty Propellers Propellers: Amendment 39-17831; Docket No. FAA-2008-1088; Directorate Identifier 2008-NE-15-AD.

(a) Effective Date

This AD is effective July 15, 2014.

(b) Affected ADs

This AD replaces AD 2008-21-07, Amendment 39-15691 (73 FR 61346, October 16, 2008).

(c) Applicability

This AD applies to Dowty Propellers model R408/6-123-F/17 propellers with blades, part numbers 697071200-18, 697071210-18, 697071227-18, 697071240-18, 697071245-18, or 697071257-18, installed.

(d) Unsafe Condition

This AD was prompted by updated service bulletins that identify terminating action to the requirements of AD 2008-21-07 (73 FR 61346, October 16, 2008). We are issuing this AD to prevent the loss of the bonded metallic leading edge (L/E) guard of the propeller, which could result in damage to the propeller or to the airplane, or injury to personnel.

(e) Compliance

Comply with this AD within the compliance times specified, unless already done.
(1) Within the next 50 flight hours (FH) or within 30 days after the effective date of this AD, whichever occurs first, inspect all affected blade assemblies where the bonded metallic L/E guard has accumulated 1,200 FH time-in-service or less since installation, in accordance with the instructions of Dowty Propellers Alert Service Bulletin (ASB) No. D8400-61-A69, Revision 1, dated September 18, 2007.
(2) Within 50 FH or 30 days, whichever occurs first, after installing a replacement blade, inspect the affected blade assembly where the bonded metallic L/E guard has accumulated 1,200 FH time- in-service or less since installation, in accordance with the instructions of Dowty Propellers ASB No. D8400-61-A69, Revision 1, dated September 18, 2007.
(3) Thereafter, at intervals not to exceed 100 FH, repeat the inspection of the affected blade assemblies in accordance with the instructions of Dowty Propellers ASB No. D8400-61-A69, Revision 1, dated September 18, 2007, until the blade bonded metallic L/E guard has accumulated more than 1,200 FH time-in-service since installation.
(4) If, during any of the inspections required by this AD, disbonding is found, apply the criteria in Appendix A of Dowty Propellers ASB No. D8400-61-A69, Revision 1, dated September 18, 2007 and, within the associated time period, repair or replace the affected blade assembly in accordance with Dowty Propellers ASBNo. D8400-61-A69, Revision 1, dated September 18, 2007.
(5) Blades that were repaired within the first 101.6 mm (4.0 inches) of the tip of the blade as specified in Appendix D of Dowty Propellers ASB No. D8400-61-A69, Revision 1, dated September 18, 2007, are eligible to continue in service for another 500 FH after accomplishment of the repair. Repair does not terminate the repetitive inspection requirements of paragraph (e)(3) of this AD.

(f) Optional Terminating Action

As optional terminating action to the repetitive inspection requirements of paragraph (e)(3) of this AD, modify the affected propeller using Dowty Propellers Service Bulletin (SB) No. D8400-61- 70, Revision 3, dated June 3, 2013, or SB No. D8400-61-83, Revision 4, dated June 3, 2013, as applicable.

(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, Engine & Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803; phone: 781-238-7761; fax: 781-238-7170; email: michael.schwetz@faa.gov.
(2) Refer to MCAI European Aviation Safety Agency AD 2007- 0223R4, dated September 30, 2013, for more information. You may examine the MCAI in the AD docket on the Internet at http://www.regulations.gov/#!documentDetail;D=FAA-2008-1088-0006.

(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.
(3) The following service information was approved for IBR on July 15,2014.
(i) Dowty Propellers Service Bulletin (SB) No. D8400-61-70, Revision 3, dated June 3, 2013.
(ii) Dowty Propellers SB No. D8400-61-83, Revision 4, dated June 3, 2013.
(4) The following service information was approved for IBR on October 31, 2008, 73 FR 61346, October 16, 2008.
(i) Dowty Propellers Alert Service Bulletin No. D8400-61-A69, Revision 1, including Appendices A and D, dated September 18, 2007; and Appendices B and C dated August 15, 2007.
(ii) Reserved.
(5) For Dowty Propellers service information identified in this AD, contact Dowty Propellers, Anson Business Park, Cheltenham Road East, Gloucester GL2 9QN, UK; phone: 44 (0) 1452 716000; fax: 44 (0) 1452 716001.
(6) You may view this service information at FAA, Engine & Propeller Directorate, 12 New England Executive Park, Burlington, MA. For information on the availability of this material at the FAA, call 781-238-7125.
(7) 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.

Discussion

We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 to revise AD 2008-21-07, Amendment 39-15691 (73 FR 61346, October 16, 2008), (``AD 2008-21-07''). AD 2008-21-07 applied to the specified products. The NPRM published in the Federal Register on December 26, 2013 (78 FR 78290). The NPRM proposed to continue to require the inspection and replacement requirements of AD 2008-21-07 and provide an optional terminating action to those requirements.

Comments

We gave the public the opportunity to participate in developing this AD. We received no comments on the NPRM (78 FR 78290, December 26, 2013). Since we issued the NPRM we received information that propeller blade, part number (P/N) 697071278-18, has not been implemented and that no parts were manufactured using this P/N. We removed propeller blade, P/N 697071278-18, from 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.

Costs of Compliance

We estimate that this AD affects 174 propellers installed on airplanes of U.S. registry. We also estimate that it will take about 4 hours per propeller to comply with this AD. The average labor rate is $85 per hour. Required parts cost about $352 per propeller. Based on these figures, we estimate the cost of this AD to U.S. operators is $120,408.

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, SubpartIII, 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

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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 DOTRegulatory 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.