AD 2008-04-03

Airworthiness directive · Main rotor hub · Airbus Helicopters AS-365N2, AS-365N3, SA-365C and 4 more

Effective
March 6, 2008
Published
February 20, 2008 · 73 FR 9178–9181
Issued
February 6, 2008
Models
AS-365N2, AS-365N3, SA-365C, SA-365C1, SA-365C2, SA-365N, SA-365N1
Data sheet
TCDSH10EU
Registered aircraft
18 matched by model
Product
Aircraft · Rotorcraft
Amendment
39-15375
Docket
FAA-2008-0164
Project
2007-SW-43-AD
Issued as
Final rule; request for comments

Unofficial copy from the Federal Register XML, document E8-2849. Only the govinfo PDF is the legal edition. DRS record last changed May 30, 2024.

On this page

Summary

We are adopting a new airworthiness directive (AD) for Eurocopter Model AS-365N2 and N3, SA-365C, C1 and C2, and SA-365N and N1 helicopters. This AD results from mandatory continuing airworthiness information (MCAI) originated by an aviation authority to identify and correct an unsafe condition on an aviation product. The European Aviation Safety Agency (EASA), the Technical Agent for France, with which we have a bilateral agreement, states in the MCAI:

This Emergency Airworthiness Directive is issued following several reports of tightening torque loss detected on the main rotor hub (MRH)-to-main rotor mast bolted attachment. These findings were made on EUROCOPTER-assembled attachments with less than 300 operating hours.

A loss of tightening torque on the MRH-to-main rotor mast attachment bolt could lead to loss of the main rotor head.

This AD requires actions that are intended to address the unsafe condition caused by a loss of tightening torque on the MRH attachment bolts.

Rule preamble

The FAA’s background, reasoning and cost estimate, published with the AD.

DatesPage 2

This AD becomes effective March 6, 2008.

The Director of the Federal Register approved the incorporation by reference of Eurocopter Emergency Alert Service Bulletin No. 62.00.22 and No. 65.44, both dated April 10, 2006, as of March 6, 2008.

We must receive comments on this AD by April 21, 2008.

AddressesPage 2

You may send comments by any of the following methods:

• Federal eRulemaking Portal: Go to http://www.regulations.gov. Follow the instructions for submitting comments.

• Fax: 202-493-2251.

• Mail: U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue, SE., Washington, DC 20590.

• Hand Delivery: U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue, SE., Washington, DC 20590, between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays.

For further information contactPage 2

Jim Grigg, Aviation Safety Engineer, FAA, Rotorcraft Directorate, Safety Management Group, Fort Worth, Texas 76193-0111, telephone (817) 222-5126, fax (817) 222-5961.

Streamlined Issuance of ADPage 2

The FAA is implementing a new process for streamlining the issuance of ADs related to MCAI. This streamlined process will allow us to adopt MCAI safety requirements in a more efficient manner and will reduce safety risks to the public. This process continues to follow all FAA AD issuance processes to meet legal, economic, Administrative Procedure Act, and Federal Register requirements. We also continue to meet our technical decision-making responsibilities to identify and correct unsafe conditions on U.S.-certificated products.

This AD references the MCAI and related service information that we considered in forming the engineering basis to correct the unsafe condition. The AD contains text copied from the MCAI and for this reason might not follow our plain language principles.

DiscussionPage 2

The European Aviation Safety Agency (EASA), which is the Technical Agent for the Member States of the European Community, has issued an MCAI in the form of EASA EAD No. 2006-0084-E, dated April 11, 2006 (referred to after this as “the MCAI”), to correct an unsafe condition for these French-certificated products. The MCAI states:

This Emergency Airworthiness Directive is issued following several reports of tightening torque loss detected on the main rotor hub (MRH)-to-main rotor mast bolted attachment. These findings were made on EUROCOPTER-assembled attachments with less than 300 operating hours.

Misinterpretation of the assembly documentation used by EUROCOPTER Marignane may have led to the assembly of these attachments with no grease applied to the nut threads, which leads to a reduction in the tightening loads.

A loss of tightening torque on the MRH-to-main rotor mast attachment bolt could lead to loss of the main rotor head. You may obtain further information by examining the MCAI and service information in the AD docket.

Relevant service informationPage 2

Eurocopter has issued Alert Service Bulletin (ASB) No. 62.00.22, applicable to Model AS-365N2 and N3, and SA-365N and N1 helicopters, and ASB 65.44, applicable to Model SA-365C, C1, and C2 helicopters, both dated April 10, 2006. The actions described in the MCAI are intended to correct the same unsafe condition as that identified in this service information.

FAA's Determination and Requirements of This ADPage 2

This product has been approved by the aviation authority of France, and is approved for operation in the United States. Pursuant to our bilateral agreement with this State of Design, we have been notified of the unsafe condition described in the MCAI and the service information. We are issuing this AD because we evaluated all pertinent information and determined the unsafe condition exists and is likely to exist or develop on other products of these same type designs.

Differences Between This AD and the MCAI or Service InformationPage 2

We have reviewed the MCAI and related service information and, in general, agree with their substance. The AD requires “inspections” rather than “checks” of the tightening torque. It also uses the term “time-in-service” rather than “flying hours”. In making these changes, we do not intend to differ substantively from the information provided in the MCAI.

These differences are highlighted in the “Differences Between the FAA AD and the MCAI” section in the AD.

Costs of CompliancePage 2

We estimate that this AD will affect 36 helicopters of U.S. registry and that it will take about 4 work hours per helicopter to perform the tightening torque inspections. The average labor rate is $80 per work-hour. Based on these figures, we estimate the total cost for this fleet of helicopters to be $11,520, or $320 per helicopter, assuming there will not be 4 or more adjacent bolts with torque less than 3.2 MdaN.

FAA's Determination of the Effective DatePage 2

An unsafe condition exists that requires the immediate adoption of this AD. The FAA has found that the risk to the flying public justifies waiving notice and comment prior to adoption of this rule because of a discovery of certain MRH attachment bolts with too little tightening torque, which could result in loss of the main rotor head, and subsequent loss of control of the helicopter. Therefore, we determined that notice and opportunity for public comment before issuing this AD are impracticable and that good cause exists for making this amendment effective in fewer than 30 days.

Comments invitedPage 3

This AD is a final rule that involves requirements affecting flight safety, and we did not precede it by notice and opportunity for public comment. We invite you to send any written relevant data, views, or arguments about this AD. Send your comments to an address listed under the ADDRESSES section. Include “Docket No. FAA-2008-0164; Directorate Identifier 2007-SW-43-AD” at the beginning of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of this AD. We will consider all comments received by the closing date and may amend this AD because of those comments.

We will post all comments we receive, without change, to http://www.regulations.gov, including any personal information you provide. We will also post a report summarizing each substantive verbal contact we receive about this AD.

Authority for This RulemakingPage 3

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 findingsPage 3

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); and

3. 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.

Adoption of the amendmentPage 3

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:

Affected TCDS · 1

The type certificate data sheets for the models this AD names, matched by model and maker.

Registered aircraft · 18

Registered aircraft whose airframe or engine model this AD names. Matched by model only, so check each against the AD’s applicability.

By aircraft maker
  • Eurocopter12 aircraft
  • Aerospatiale3 aircraft
  • Eurocopter France3 aircraft
By year built
19872008
Registered aircraft by year built: 13 aircraft
19871
19881
19892
19951
19982
19991
20001
20021
20041
20082

5 with no year recorded

By model

Aircraft

See all 18 aircraft