AD 99-06-03
final rule
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Airbus Helicopters | AS-365N2 | Airworthiness Directives; Eurocopter France Model AS-365N, N1, and N2 Helicopters |
| aircraft | Airbus Helicopters | SA-365N | Airworthiness Directives; Eurocopter France Model AS-365N, N1, and N2 Helicopters |
| aircraft | Airbus Helicopters | SA-365N1 | Airworthiness Directives; Eurocopter France Model AS-365N, N1, and N2 Helicopters |
Unsafe Condition
Disbonding of the metal center section of the main rotor head frequency adapter from the elastomer caused by a lack of adherence during the production process, leading to increased vibrations and reduced controllability of the helicopter.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Determine the part number, serial number, and date of manufacture of the main rotor head frequency adapter. If the adapter is part number 704A33-640-031 (E1T2624-01A) or 365A31-1858-01 (pairs) manufactured before April 1, 1991, with serial number ≤8188, or part number 704A33-640-046 (E1T3023-01) or 365A31-1858-02 (pairs) manufactured before April 1, 1991, with serial number ≤3122, replace it with an airworthy frequency adapter.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
within the next 100 hours time-in-service or 6 calendar months, whichever occurs first, unless accomplished previously
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
Eurocopter France Model AS-365N, N1, and N2 helicopters, certificated in any category.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Main Rotor Head Frequency Adapter
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_99-06-03.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 99-06-03 Document Type: AD Final Rules Docket Number: 97-SW-64-AD Subject Heading: Airworthiness Directives; Eurocopter France Model AS-365N, N1, and N2 Helicopters Subject: Main Rotor Head Frequency Adapter Status: Current Citation: Federal Register: March 09, 1999 (Volume 64, Number 45) Citation Publish Date: 03/09/1999 Effective Date: 04/13/1999 Make: Airbus Helicopters Model: AS-365N2 | SA-365N | SA-365N1 Product Type: Aircraft Product Subtype: Rotorcraft Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 [64 11375 NO. 45 03/09/99] Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 99-06-03 CITATION: [Federal Register: March 09, 1999 (Volume 64, Number 45)] PAGE NUMBER: [Page ?????] DOCKET NUMBER: 97-SW-64-AD AMENDMENT: 39-11067 AD NUMBER: 99-06-03 SUBJECT HEADING: Airworthiness Directives; Eurocopter France Model AS-365N, N1, and N2 Helicopters ACTION: Final Rule SUMMARY: This amendment adopts a new airworthiness directive (AD), applicable to Eurocopter France Model AS-365N, N1, and N2 helicopters, that requires inspecting the helicopter to determine if a certain main rotor head frequency adapter (frequency adapter) is installed and, if so, replacing it with an airworthy frequency adapter. This amendment is prompted by a report of disbonding of the metal center section of a frequency adapter from the elastomer on a main rotor head caused by a lack of adherence during the production process. The actions specified by this AD are intended to prevent increased vibrations caused by disbonding of the center section of a frequency adapter from the elastomer and subsequent reduced controllability of the helicopter. DATES: Effective April 13, 1999. ADDRESSES: FOR FURTHER INFORMATION CONTACT: Mike Mathias, Aerospace Engineer, Rotorcraft Standards Staff, Rotorcraft Directorate, FAA, 2601 Meacham Blvd., Fort Worth, Texas 76137, telephone (817) 222-5123, fax (817) 222-5961. SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) to include an AD that is applicable to Eurocopter France Model AS-365N, N1, and N2 helicopters was published in the Federal Register on June 5, 1998 (63 FR 30662). That action proposed to require inspecting for certain frequency adapters and if they are installed, replacing them with airworthy frequency adapters. Interested persons have been afforded an opportunity to participate in the making of this amendment. No comments were received on the proposal or the FAA's determination of the cost to the public. The FAA has determined that air safety and the public interest require the adoption of the rule as proposed. The FAA estimates that 91 helicopters of U.S. registry will be affected by this AD, that it will take approximately 6 work hours per helicopter to accomplish the required actions, and that the average labor rate is $60 per work hour. Required parts will cost approximately $5,200 per helicopter. Based on these figures, the total cost impact of this AD on U.S. operators is estimated to be $505,960. The regulations adopted herein will not have substantial direct effects 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. Therefore, in accordance with Executive Order 12612, it is determined that this final rule will not have sufficient federalism implications to warrant the preparation of a Federalism Assessment. For the reasons discussed above, I certify that this action (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) if promulgated, 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. A copy of the draft regulatory evaluation prepared for this action is contained in the Rules Docket. A copy of it may be obtained by contacting the Rules Docket at the FAA, Office of the Regional Counsel, Southwest Region, Attention: Rules Docket No. 97-SW-64-AD, 2601 Meacham Blvd., Room 663, Fort Worth, Texas 76137. List of Subjects in 14 CFR Part 39 Air transportation, Aircraft, Aviation safety, Safety. Adoption of the Amendment Accordingly, pursuant to the authority delegated to me by the Administrator, the Federal Aviation Administration amends part 39 of the Federal Aviation Regulations (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. Section 39.13 is amended by adding a new airworthiness directive (AD) to read as follows: REGULATORY TEXT: 99-06-03 EUROCOPTER FRANCE: Amendment 39-11067. Docket No. 97-SW-64-AD. Applicability: Model AS-365N, N1, and N2 helicopters, certificated in any category. NOTE 1: This AD applies to each helicopter identified in the preceding applicability provision, regardless of whether it has been modified, altered, or repaired in the area subject to the requirements of this AD. For helicopters that have been modified, altered, or repaired so that the performance of the requirements of this AD is affected, the owner/operator must use the authority provided in paragraph (c) to request approval from the FAA. This approval may address either no action, if the current configuration eliminates the unsafe condition, or different actions necessary to address the unsafe condition described in this AD. Such a request should include an assessment of the effect of the changed configuration on the unsafe condition addressed by this AD. In no case does the presence of any modification, alteration, or repair remove any helicopter from the applicability of this AD. Compliance: Required within the next 100 hours time-in-service or 6 calendar months, whichever occurs first, unless accomplished previously. To prevent vibrations caused by disbonding of the center section of a frequency adapter from the elastomer on the main rotor head and subsequent reduced controllability of the helicopter, accomplish the following: (a) Determine the part number, serial number, and date of manufacture of the main rotor head frequency adapter (frequency adapter). (b) If a frequency adapter part number (P/N) 704A33-640-031 (E1T2624-01A), or delivered in pairs under the P/N 365A31-1858-01, manufactured before April 1, 1991, with a serial number (S/N) equal to or less than 8188, or P/N 704A33-640-046 (E1T3023-01), or delivered in pairs under the P/N 365A31-1858-02, manufactured before April 1, 1991, with a S/N equal to or less than 3122, is installed, remove the frequency adapter and replace it with an airworthy frequency adapter. NOTE 2: Eurocopter France AS 365 Service Bulletin No. 01.00.44, dated May 9, 1996, pertains to the subject of this AD. (c) An alternative method of compliance or adjustment of the compliance time that provides an acceptable level of safety may be used if approved by the Manager, FAA, Rotorcraft Directorate, Rotorcraft Standards Staff. Operators shall submit their requests through an FAA Principal Maintenance Inspector, who may concur or comment and then send it to the Manager, Rotorcraft Standards Staff. NOTE 3: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Rotorcraft Standards Staff. (d) Special flight permits may be issued in accordance with sections 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 21.197 and 21.199) to operate the helicopter to a location where the requirements of this AD can be accomplished. NOTE 4: The subject of this AD is addressed in Direction General De L'Aviation Civile (France) AD 96-117-040(B), dated June 19, 1996. (e) This amendment becomes effective on April 13, 1999. FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_99-06-03.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 99-06-03 Document Type: AD Final Rules Docket Number: 97-SW-64-AD Subject Heading: Airworthiness Directives; Eurocopter France Model AS-365N, N1, and N2 Helicopters Subject: Main Rotor Head Frequency Adapter Status: Current Citation: Federal Register: March 09, 1999 (Volume 64, Number 45) Citation Publish Date: 03/09/1999 Effective Date: 04/13/1999 Make: Airbus Helicopters Model: AS-365N2 | SA-365N | SA-365N1 Product Type: Aircraft Product Subtype: Rotorcraft Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 [64 11375 NO. 45 03/09/99] Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 99-06-03 CITATION: [Federal Register: March 09, 1999 (Volume 64, Number 45)] PAGE NUMBER: [Page ?????] DOCKET NUMBER: 97-SW-64-AD AMENDMENT: 39-11067 AD NUMBER: 99-06-03 SUBJECT HEADING: Airworthiness Directives; Eurocopter France Model AS-365N, N1, and N2 Helicopters ACTION: Final Rule SUMMARY: This amendment adopts a new airworthiness directive (AD), applicable to Eurocopter France Model AS-365N, N1, and N2 helicopters, that requires inspecting the helicopter to determine if a certain main rotor head frequency adapter (frequency adapter) is installed and, if so, replacing it with an airworthy frequency adapter. This amendment is prompted by a report of disbonding of the metal center section of a frequency adapter from the elastomer on a main rotor head caused by a lack of adherence during the production process. The actions specified by this AD are intended to prevent increased vibrations caused by disbonding of the center section of a frequency adapter from the elastomer and subsequent reduced controllability of the helicopter. DATES: Effective April 13, 1999. ADDRESSES: FOR FURTHER INFORMATION CONTACT: Mike Mathias, Aerospace Engineer, Rotorcraft Standards Staff, Rotorcraft Directorate, FAA, 2601 Meacham Blvd., Fort Worth, Texas 76137, telephone (817) 222-5123, fax (817) 222-5961. SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) to include an AD that is applicable to Eurocopter France Model AS-365N, N1, and N2 helicopters was published in the Federal Register on June 5, 1998 (63 FR 30662). That action proposed to require inspecting for certain frequency adapters and if they are installed, replacing them with airworthy frequency adapters. Interested persons have been afforded an opportunity to participate in the making of this amendment. No comments were received on the proposal or the FAA's determination of the cost to the public. The FAA has determined that air safety and the public interest require the adoption of the rule as proposed. The FAA estimates that 91 helicopters of U.S. registry will be affected by this AD, that it will take approximately 6 work hours per helicopter to accomplish the required actions, and that the average labor rate is $60 per work hour. Required parts will cost approximately $5,200 per helicopter. Based on these figures, the total cost impact of this AD on U.S. operators is estimated to be $505,960. The regulations adopted herein will not have substantial direct effects 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. Therefore, in accordance with Executive Order 12612, it is determined that this final rule will not have sufficient federalism implications to warrant the preparation of a Federalism Assessment. For the reasons discussed above, I certify that this action (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) if promulgated, 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. A copy of the draft regulatory evaluation prepared for this action is contained in the Rules Docket. A copy of it may be obtained by contacting the Rules Docket at the FAA, Office of the Regional Counsel, Southwest Region, Attention: Rules Docket No. 97-SW-64-AD, 2601 Meacham Blvd., Room 663, Fort Worth, Texas 76137. List of Subjects in 14 CFR Part 39 Air transportation, Aircraft, Aviation safety, Safety. Adoption of the Amendment Accordingly, pursuant to the authority delegated to me by the Administrator, the Federal Aviation Administration amends part 39 of the Federal Aviation Regulations (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. Section 39.13 is amended by adding a new airworthiness directive (AD) to read as follows: REGULATORY TEXT: 99-06-03 EUROCOPTER FRANCE: Amendment 39-11067. Docket No. 97-SW-64-AD. Applicability: Model AS-365N, N1, and N2 helicopters, certificated in any category. NOTE 1: This AD applies to each helicopter identified in the preceding applicability provision, regardless of whether it has been modified, altered, or repaired in the area subject to the requirements of this AD. For helicopters that have been modified, altered, or repaired so that the performance of the requirements of this AD is affected, the owner/operator must use the authority provided in paragraph (c) to request approval from the FAA. This approval may address either no action, if the current configuration eliminates the unsafe condition, or different actions necessary to address the unsafe condition described in this AD. Such a request should include an assessment of the effect of the changed configuration on the unsafe condition addressed by this AD. In no case does the presence of any modification, alteration, or repair remove any helicopter from the applicability of this AD. Compliance: Required within the next 100 hours time-in-service or 6 calendar months, whichever occurs first, unless accomplished previously. To prevent vibrations caused by disbonding of the center section of a frequency adapter from the elastomer on the main rotor head and subsequent reduced controllability of the helicopter, accomplish the following: (a) Determine the part number, serial number, and date of manufacture of the main rotor head frequency adapter (frequency adapter). (b) If a frequency adapter part number (P/N) 704A33-640-031 (E1T2624-01A), or delivered in pairs under the P/N 365A31-1858-01, manufactured before April 1, 1991, with a serial number (S/N) equal to or less than 8188, or P/N 704A33-640-046 (E1T3023-01), or delivered in pairs under the P/N 365A31-1858-02, manufactured before April 1, 1991, with a S/N equal to or less than 3122, is installed, remove the frequency adapter and replace it with an airworthy frequency adapter. NOTE 2: Eurocopter France AS 365 Service Bulletin No. 01.00.44, dated May 9, 1996, pertains to the subject of this AD. (c) An alternative method of compliance or adjustment of the compliance time that provides an acceptable level of safety may be used if approved by the Manager, FAA, Rotorcraft Directorate, Rotorcraft Standards Staff. Operators shall submit their requests through an FAA Principal Maintenance Inspector, who may concur or comment and then send it to the Manager, Rotorcraft Standards Staff. NOTE 3: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Rotorcraft Standards Staff. (d) Special flight permits may be issued in accordance with sections 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 21.197 and 21.199) to operate the helicopter to a location where the requirements of this AD can be accomplished. NOTE 4: The subject of this AD is addressed in Direction General De L'Aviation Civile (France) AD 96-117-040(B), dated June 19, 1996. (e) This amendment becomes effective on April 13, 1999. FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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