2019-04528. Airworthiness Directives; MD Helicopters, Inc. (MDHI), Helicopters

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Final rule.

SUMMARY:

We are adopting a new airworthiness directive (AD) for MDHI Model 369A, 369D, 369E, 369FF, 369H, 369HE, 369HM, 369HS, 500N, and 600N helicopters. This AD requires inspecting each main rotor blade (MRB) for a crack. This AD was prompted by reports of cracked MRBs. The actions of this AD are intended to address an unsafe condition on these helicopters.

DATES:

This AD is effective April 17, 2019.

ADDRESSES:

For Helicopter Technology Company, LLC, service information identified in this final rule, contact Helicopter Technology Company, LLC, 12902 South Broadway, Los Angeles, CA 90061; telephone [phone]; or at www.helicoptertech.com. For MD Helicopters service information identified in this final rule, contact MD Helicopters, Inc., Attn: Customer Support Division, 4555 E. McDowell Rd., Mail Stop M615, Mesa, AZ 85215-9734; telephone [phone]; fax [phone]; or at http://www.mdhelicopters.com. You may review a copy of the referenced service information at the FAA, Office of the Regional Counsel, Southwest Region, 10101 Hillwood Pkwy, Room 6N-321, Fort Worth, TX 76177.

Examining the AD Docket

You may examine the AD docket on the internet at http://www.regulations.gov by searching for and locating Docket No. FAA-2018-0991; or in person at Docket Operations between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD docket contains this AD, the economic evaluation, any comments received, and other information. The street address for Docket Operations (phone: [phone]) is U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue SE, Washington, DC 20590.

FOR FURTHER INFORMATION CONTACT:

Galib Abumeri, Aviation Safety Engineer, Los Angeles ACO Branch, Compliance & Airworthiness Division, FAA, 3960 Paramount Blvd., Lakewood, CA 90712; telephone [phone]; email [e-mail].

SUPPLEMENTARY INFORMATION:

Discussion

On November 26, 2018, at 83 FR 60376, 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 MDHI Model 369A, 369D, 369E, 369FF, 369H, 369HE, 369HM, 369HS, 500N, and 600N helicopters with a Helicopter Technology Company, LLC (HTC), MRB part number 369A1100, 369D21100, 369D21102, 369D21120, 369D21121, 369D21123, 500P2100, or 500P2300 installed. The NPRM was prompted by reports of two operators finding cracks on an HTC-manufactured MRB and proposed to require repetitively inspecting each MRB trim tab for a crack. The proposed requirements were intended to prevent failure of an MRB and subsequent loss of control of the helicopter.

In the “Costs of Compliance” section, the NPRM stated an incorrect number of U.S.-registered helicopters affected by this AD and subsequently, an incorrect estimated cost of the inspection for the U.S. fleet. We have corrected the cost information in this Final rule.

Comments

We gave the public the opportunity to participate in developing this AD, but we did not receive any comments on the NPRM.

FAA's Determination

We have reviewed the relevant information and determined that an unsafe condition exists and is likely to exist or develop on other products of these same type designs and that air safety and the public interest require adopting the AD requirements as proposed.

Related Service Information

We reviewed HTC Mandatory Service Bulletin Notice No. 2100-9, dated May 25, 2017 (SB 2100-9), which contains procedures for inspecting each MRB for a crack in an area adjacent to the inboard edge of the MRB trim tab.

We also reviewed MD Helicopters Service Bulletin No. SB369D-221, SB369E-119, SB369F-106, SB369H-257, SB500N-057, and SB600N-069, each dated April 2, 2018. This service information specifies inspecting the MRBs for cracks near the trim tab by following the instructions in SB 2100-9.

Differences Between This AD and the Service Information

The service information specifies procedures for inspecting each MRB for nicks, gouges, and scratches. This AD does not, as the unsafe condition concerns a crack in the MRB.

Costs of Compliance

We estimate that this AD affects 730 helicopters of U.S. Registry. We estimate that operators may incur the following costs in order to comply with this AD. Labor costs are estimated at $85 per work-hour.

Inspecting one MRB requires about 0.1 work-hour, for an estimated cost per helicopter of $43 for the 705 MDHI Model 369-series and 500N helicopters (5 MRBs), $51 for the 25 MDHI Model 600N helicopters (6 MRBs), and a total estimated cost of $31,590 for the U.S. fleet per inspection cycle.

If required, replacing one MRB requires about 3 work-hours and parts cost about $13,000 for a total estimated cost of $13,255 per MRB.

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, 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.

Regulatory Findings

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, 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.

List of Subjects in 14 CFR Part 39

• Air transportation
• Aircraft
• Aviation safety
• Incorporation by reference
• Safety

Adoption of the Amendment

Accordingly, under the authority delegated to me by the Administrator, the FAA amends 14 CFR part 39 as follows:

PART 39—AIRWORTHINESS DIRECTIVES

1. The authority citation for part 39 continues to read as follows:

Authority: 49 U.S.C. 106(g), 40113, 44701.

§ 39.13

[Amended]

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

2019-05-04 MD Helicopters, Inc.: Amendment 39-19586; Docket No. FAA-2018-0991; Product Identifier 2017-SW-050-AD.

(a) Applicability

This AD applies to MD Helicopters, Inc., Model 369A, 369D, 369E, 369FF, 369H, 369HE, 369HM, 369HS, 500N, and 600N helicopters, certificated in any category, with a main rotor blade (MRB) part number 369A1100, 369D21100, 369D21102, 369D21120, 369D21121, 369D21123, 500P2100, or 500P2300, all dash numbers, installed.

(b) Unsafe Condition

This AD defines the unsafe condition as a crack in an MRB. This condition could result in failure of the MRB and subsequent loss of control of the helicopter.

(c) Effective Date

This AD becomes effective April 17, 2019.

(d) Compliance

You are responsible for performing each action required by this AD within the specified compliance time unless it has already been accomplished prior to that time.

(e) Required Actions

Within 25 hours time-in-service, and thereafter at each 100-hour inspection or annual inspection, whichever occurs first:

(1) Using a 10X or higher power magnifying glass and a light, inspect each MRB trim tab end at the trailing edge corner where the trim tab and MRB meet for a crack. If there is a crack, before further flight, replace the MRB.

(2) Using a 10X or higher power magnifying glass and a light, inspect the top and bottom surface of each MRB adjacent to the inboard trim tab corner for a crack, from the trailing edge towards the leading edge. If there is a crack, before further flight, replace the MRB.

(f) Alternative Methods of Compliance (AMOCs)

(1) The Manager, Los Angeles ACO Branch, FAA, may approve AMOCs for this AD. Send your proposal to: Galib Abumeri, Aviation Safety Engineer, Los Angeles ACO Branch, Compliance & Airworthiness Division, FAA, 3960 Paramount Blvd., Lakewood, CA 90712; telephone [phone]; email [e-mail].

(2) For operations conducted under a 14 CFR part 119 operating certificate or under 14 CFR part 91, subpart K, we suggest that you notify your principal inspector, or lacking a principal inspector, the manager of the local flight standards district office or certificate holding district office before operating any aircraft complying with this AD through an AMOC.

(g) Additional Information

(1) Helicopter Technology Company, LLC, Mandatory Service Bulletin Notice No. 2100-9, dated May 25, 2017, which is not incorporated by reference, contains additional information about the subject of this AD. For Helicopter Technology Company, LLC, service information identified in this AD, contact Helicopter Technology Company, LLC, 12902 South Broadway, Los Angeles, CA 90061; telephone [phone]; or at www.helicoptertech.com.

(2) MD Helicopters Service Bulletin No. SB369D-221, SB369E-119, SB369F-106, SB369H-257, SB500N-057, and SB600N-069, each dated April 2, 2018, which are not incorporated by reference, contain additional information about the subject of this AD. For MD Helicopters service information identified in this AD, contact MD Helicopters, Inc., Attn: Customer Support Division, 4555 E. McDowell Rd., Mail Stop M615, Mesa, AZ 85215-9734; telephone [phone]; fax [phone]; or at http://www.mdhelicopters.com.

(3) You may review a copy of this service information at the FAA, Office of the Regional Counsel, Southwest Region, 10101 Hillwood Pkwy, Room 6N-321, Fort Worth, TX 76177.

(h) Subject

Joint Aircraft Service Component (JASC) Code: 6210, Main Rotor Blade.

Issued in Fort Worth, Texas, on February 28, 2019.

Scott A. Horn,

Deputy Director for Regulatory Operations, Compliance & Airworthiness Division, Aircraft Certification Service.