AD 2016-21-03

This AD is effective November 25, 2016.

For service information identified in this final rule, contact Airbus Helicopters, Inc., 2701 N. Forum Drive, Grand Prairie, TX 75052; telephone (972) 641-0000 or (800) 232-0323; fax (972) 641-3775; or at http://www.airbushelicopters.com/techpub. You may review the referenced service information at the FAA, Office of the Regional Counsel, Southwest Region, 10101 Hillwood Pkwy, Room 6N-321, Fort Worth, TX 76177.

Matt Wilbanks, Aviation Safety Engineer, Regulations and Policy Group, Rotorcraft Directorate, FAA, 10101 Hillwood Pkwy., Room 6N-321, Fort Worth, TX 76177; telephone (817) 222-5110; email matt.wilbanks@faa.gov.

On August 18, 2014, at 79 FR 48696, 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 Airbus Helicopters Model MBB-BK 117 C-2 helicopters with a lateral duplex trim actuator, part number (P/N) 418-00878-050 or P/N 418-00878-051, or a longitudinal duplex trim actuator, P/N 418-00878-000 or P/N 418-00878-001, installed. The NPRM proposed to require repetitively inspecting the lateral and longitudinal trim actuator output levers for correct torque of the nuts. The proposed requirements were intended to prevent a loose attachment screw, which could result in movement of the output lever in an axial direction, contact of a bolt connecting the control rod to an output lever with the actuator housing, and subsequent loss of helicopter control.

The NPRM was prompted by AD No. 2013-0182, dated August 12, 2013, issued by EASA, which is the Technical Agent for the Member States of the European Union, to correct an unsafe condition for Airbus Helicopters Model MBB-BK 117 C-2 helicopters with a lateral duplex trim actuator, P/N 418-00878-050 or P/N 418-00878-051, or with a longitudinal duplex trim actuator, P/N 418-00878-000 or P/N 418-00878-001. EASA advises that under unfavorable circumstances, a total loss of the trim actuator output lever attachment screw could lead to a restriction of the lateral and longitudinal control range. According to EASA, without the attachment screw, the output lever can move in the axial direction. This condition, if not detected, could cause the bolt that connects the control rod to the output lever to make contact with actuator housing, possibly resulting in reduced control of the helicopter.

To prevent this condition, EASA requires an initial torque check of the lateral and longitudinal trim actuator output lever attachment screws, the application of a torque marking, and repetitive inspections for correct torque thereafter. The EASA AD's requirements are considered an interim solution, pending a terminating modification.

Since the issuance of EASA AD No. 2013-0182, Eurocopter Deutschland GmbH has changed its name to Airbus Helicopters Deutschland GmbH.

We gave the public the opportunity to participate in developing this AD, but we received no comments on the NPRM (79 FR 48696, August 18, 2014).

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

We consider this AD to be an interim action because Airbus Helicopters is currently developing a modification that will address the unsafe condition identified in this AD. Once this modification is developed, approved and available, we might consider additional rulemaking.

We reviewed Eurocopter (now Airbus Helicopters) Alert Service Bulletin MBB-BK117 C-2-67A-020, Revision 0, dated June 18, 2013 (ASB), which advises of a design review that showed that a loss of the attachment screw of the trim actuator output lever could restrict the lateral and longitudinal control range. The ASB consequently calls for an initial torque check and application of torque markings of the self-locking nuts, and subsequent repetitive inspections to maintain the proper torque.

We estimate that this AD affects 100 helicopters of U.S. Registry and that labor costs average $85 per work-hour. Based on these estimates, we expect the following costs:

• Applying torque and torque marking to the lateral and longitudinal trim actuator output levers requires 1 work-hour for a labor cost of $85. No parts are needed, so the cost for the U.S. fleet totals $8,500.

• Visually inspecting for correct torque requires 0.5 work-hour for a labor cost of about $43. No parts are needed, so the total cost for the U.S. fleet is $4,300 per inspection cycle.

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):