AD 2013-20-13

This AD is effective December 10, 2013.

The Director of the Federal Register approved the incorporation by reference of a certain document listed in this AD as of December 10, 2013.

For service information identified in this AD, contact Bell Helicopter Textron Canada Limited, 12,800 Rue de l'Avenir, Mirabel, Quebec J7J1R4; telephone (450) 437-2862 or (800) 363-8023; fax (450) 433-0272; or at http://www.bellcustomer.com/files/. You may review the referenced service information at the FAA, Office of the Regional Counsel, Southwest Region, 2601 Meacham Blvd., Room 663, Fort Worth, Texas 76137.

Chinh Vuong, Aviation Safety Engineer, Safety Management Group, Rotorcraft Directorate, FAA, 2601 Meacham Blvd., Fort Worth, Texas 76137; telephone (817) 222-5110; email chinh.vuong@faa.gov.

On June 7, 2013, at 78 FR 34280, the Federal Register published our notice of proposed rulemaking (NPRM), which proposed to amend 14 CFR part 39 by adding an AD that would apply to Bell Model 206B helicopters, serial number (S/N) 004 through 4675, including helicopters converted from Model 206A and Model 206L helicopters, S/N 45001 through 45153, and 46601 through 46617. The NPRM proposed to require installing a placard on the instrument panel below the NR/N2 dual tachometer and revising the Operating Limitations section of the Model 206B RFM and 206L RFM to limit steady-state operation between speeds of 75% and 88%. The proposed requirements were intended to alert pilots to avoid certain engine speeds during steady-state operations, prevent failure of the third stage engine turbine, engine power loss, and subsequent loss of control of the helicopter.

The NPRM was prompted by AD No. CF-2007-13R2, dated November 10, 2009, issued by Transport Canada Civil Aviation (TCCA), which is the aviation authority for Canada. TCCA issued AD No. CF-2007-13R2 to correct an unsafe condition for certain Model 206B (including those converted from Model 206A) and 206L helicopters. TCCA advises of several failures of third stage turbine wheels used in Rolls Royce 250-C20. According to TCCA, Rolls Royce has determined that detrimental vibrations can occur within a particular range of turbine speeds, and may be a contributing factor to these failures. Bell has revised the RFM and has provided a corresponding decal to inform pilots to avoid steady-state operations between 75% and 88% turbine speeds.

The TCCA AD requires amending the RFMs, advising pilots of the change, and installing a decal as described in Bell Alert Service Bulletin (ASB) No. 206-07-115, Revision C, dated February 4, 2009, for Model 206B helicopters (ASB 206-07-115) and Bell ASB No. 206L-07-146, Revision B, dated March 3, 2009, for Model 206L helicopters (ASB 206L-07-146).

After our NPRM (78 FR 34280, June 7, 2013) was published, we received comments from one commenter.

Rolls-Royce Corporation requested that in addition to requiring the placard on the instrument panel, we allow operators the option to temporarily mark the N r /N p gauge with colored tape, to provide a more visual aide to the pilot for the speed avoidance zone.

We disagree. Marking the glass surface of the gauge can create parallax issues when viewing the avoidance ranges on the gauge, resulting in erroneous readings.

These helicopters have been approved by the aviation authority of Canada and are approved for operation in the United States. Pursuant to our bilateral agreement with Canada, TCCA, its technical representative, has notified us of the unsafe condition described in the TCCA AD. We are issuing this AD because we evaluated all information provided by TCCA, reviewed the relevant information, considered the comment received, and determined the unsafe condition exists and is likely to exist or develop on other helicopters of the same type design and that air safety and the public interest require adopting the AD requirements as proposed.

The TCCA AD requires compliance within 10 calendar days, while this AD requires compliance within 30 days.

Bell has issued ASB 206-07-115 and ASB 206L-07-146, which contain procedures for installing a placard on the instrument panel below the main rotor RPM (Nr)/power turbine RPM (N2) dual tachometer and for inserting the RFM changes into the flight manual.

We estimate that this AD will affect 970 helicopters of U.S. Registry. Based on an average labor rate of $85 per hour, we estimate that operators will incur the following costs in order to comply with this AD. Amending the RFM will require about 0.5 work-hour, for a cost per helicopter of about $43 and a cost to U.S. operators of $41,710. Installing the decal will require about 0.2 work-hour and required parts will cost $20, for a cost per helicopter of $37 and a cost to U.S. operators of $35,890. Based on these estimates, the total cost of this AD is $80 per helicopter and $77,600 for the U.S. operator fleet.

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 helicopters identified in this rulemaking action.

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 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.

We prepared an economic evaluation of the estimated costs to comply with this AD and placed it in the AD docket.

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):