AD 2014-14-01

This AD becomes effective August 15, 2014.

For service information identified in this AD, contact Rolls-Royce plc, Corporate Communications, P.O. Box 31, Derby, England, DE248BJ; phone: 011-44-1332-242424; fax: 011-44-1332-249936; email: http://www.rolls-royce.com/contact/civil_team.jsp; or Web site: https://www.aeromanager.com. 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.

Kenneth Steeves, Aerospace Engineer, Engine Certification Office, FAA, Engine & Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803; phone: (781) 238-7765; fax: (781) 238-7199; email: Kenneth.Steeves@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 3, 2014 (79 FR 11722). The NPRM proposed to correct an unsafe condition for the specified products. The MCAI states:

An operator of an A330 aeroplane fitted with RR Trent 772B engines experienced an engine uncontained multiple turbine blade failure. Investigation results showed that High-Pressure/Intermediate-Pressure (HP/IP) oil vent tubes may be affected by carbon deposit and may also be damaged by their outer heat shields, which in this case led to combustion inside the tube. The consequent chain of events resulted in an engine internal fire which caused the failure of the IP turbine disc drive arm.

This condition, if not corrected, could lead to uncontained multiple turbine blade failures or an HP/IP turbine disc burst, possibly resulting in damage to, and reduced control of, the aeroplane.

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

RR requested that we define the failure mode as IP turbine disc drive arm failure and multiple IP turbine blade release to be consistent with descriptions in the RR service bulletin and the European Aviation Safety Agency (EASA) AD.

We disagree. EASA AD 2013-0190, dated August 20, 2013, states that the failure mode is multiple turbine blade failures or HP/IP turbine disc burst. We did not change this AD.

RR requested that we modify the compliance date to be consistent with the compliance date required in EASA AD 2013-0190, dated August 20, 2013.

We disagree. EASA AD 2013-0190, dated August 20, 2013 required compliance by December 31, 2018. We proposed compliance at next shop visit or December 31, 2018, whichever comes first, to achieve more timely mitigation of the unsafe condition. We did not change this AD.

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

We estimate that this AD affects about 72 engines installed on airplanes of U.S. registry. We also estimate that it will take about 1 hour per engine to comply with this AD. The average labor rate is $85 per hour. There are no required parts. Based on these figures, we estimate the cost of this AD on U.S. operators to be $6,120.

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):