AD 2014-14-02

This AD becomes effective August 15, 2014.

For service information identified in this AD, contact Pratt & Whitney Canada Corp., 1000 Marie-Victorin, Longueuil, Quebec, Canada, J4G 1A1; phone: 800-268-8000; fax: 450-647-2888; Web site: www.pwc.ca. You may view this service information at the 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.

Kevin Dickert, Aerospace Engineer, Engine Certification Office, FAA, Engine & Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803; phone: 781-238-7117; fax: 781-238-7199; email: kevin.dickert@faa.gov.

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 March 21, 2014 (79 FR 15707). The NPRM proposed to correct an unsafe condition for the specified products. The MCAI states:

There have been reported incidences of fuel leaks at the interface between the flexible fuel manifold and the fuel nozzle. On occasion, these events resulted in an engine fire on PW100 series engine installations. The data indicates that nearly all of the subject manifold fuel leaks were caused by inadequate B-nut torque application during installation, after maintenance work was performed on the fuel nozzle/manifold.

Sealing of the fitting connections between the fuel manifolds and the fuel nozzle adapters is achieved through conical metal-to-metal surface seating. An additional O-ring seal on the fitting was installed to arrest any fuel leak past the conical sealing surfaces. In-service experience has indicated that leakage past the sealing surfaces, as a result of improper torquing during installation of the manifold, may not be immediately evident until the failure of the O-ring seal allows the fuel to leak into the nacelle area.

We gave the public the opportunity to participate in developing this AD. We considered the comment received.

UTair Aviation JSC requested that we mandate incorporation of P&WC Service Bulletins (SBs) PW100-72-21841, Revision No. 1, dated November 29, 2013; and PW100-72-21848, Revision No. 1, dated November 15, 2013, in the AD. The commenter suggested that incorporation by reference of these SBs would improve safety compared to the compliance proposed in the NPRM (79 FR 15707, March 21, 2014).

We disagree. We note that prior to implementation of these SBs, an operator would need to remove the affected O-ring seals, which would fulfill the requirements of this AD. We do not find that requiring accomplishing these service bulletins through incorporation by reference in this AD is necessary. We did not change this AD.

We reviewed the available data, including the comment received, and determined that air safety and the public interest require adopting the AD as proposed.

We estimate that this AD affects about 150 engines installed on airplanes of U.S. registry. We also estimate that it would take about 2.5 hours per engine to perform the inspection or replacement required by this AD. The average labor rate is $85 per hour. Based on these figures, we estimate the cost of this AD on U.S. operators to be $31,875.

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.

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.

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:

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