Airworthiness Directives; Airbus Helicopters Deutschland GmbH Helicopters

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

The FAA proposes to adopt a new airworthiness directive (AD) for certain Airbus Helicopters Deutschland GmbH Model BO-105A, BO-105C, BO-105S, and BO-105LS A-3 helicopters. This proposed AD was prompted by the FAA's determination that aging of the elastomeric material in a tension torsion strap (TT-strap) could affect the structural characteristics of the TT-strap. This proposed AD would require replacement of certain TT-straps with serviceable parts and implementation of a new storage life limit for TT-straps, as specified in a European Aviation Safety Agency (now European Union Aviation Safety Agency) (EASA) AD, which is proposed for incorporation by reference (IBR). The FAA is proposing this AD to address the unsafe condition on these products.

DATES:

The FAA must receive comments on this proposed AD by April 26, 2021.

ADDRESSES:

You may send comments, using the procedures found in 14 CFR 11.43 and 11.45, by any of the following methods:

• Federal eRulemaking Portal: Go to https://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: Deliver to Mail address above between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays.

For material that is proposed for IBR in this AD, contact the EASA, Konrad-Adenauer-Ufer 3, 50668 Cologne, Germany; telephone +49 221 8999 000; email ADs@easa.europa.eu; internet www.easa.europa.eu. You may find this material on the EASA website at https://ad.easa.europa.eu. You may view this material at the FAA, Office of the Regional Counsel, Southwest Region, 10101 Hillwood Pkwy, Room 6N-321, Fort Worth, TX 76177. For information on the availability of this material at the FAA, call 817-222-5110. It is also available in the AD docket on the internet at https://www.regulations.gov by searching for and locating Docket No. FAA-2021-0143.

Examining the AD Docket

You may examine the AD docket on the internet at https://www.regulations.gov by searching for and locating Docket No. FAA-2021-0143; 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 NPRM, any comments received, and other information. The street address for Docket Operations is listed above. Comments will be available in the AD docket shortly after receipt.

FOR FURTHER INFORMATION CONTACT:

Blaine Williams, Aviation Safety Engineer, Los Angeles ACO Branch, 3960 Paramount Boulevard, Lakewood, CA 90712-4137; telephone 562-627-5371; email blaine.willaims@faa.gov.

SUPPLEMENTARY INFORMATION:

Comments Invited

The FAA invites you to send any written relevant data, views, or arguments about this proposal. Send your comments to an address listed under ADDRESSES. Include “Docket No. FAA-2021-0143; Product Identifier 2019-SW-024-AD” at the beginning of your comments. The most helpful comments reference a specific portion of the proposal, explain the reason for any recommended change, and include supporting data. The FAA will consider all comments received by the closing date and may amend this proposal because of those comments.

Except for Confidential Business Information (CBI) as described in the following paragraph, and other information as described in 14 CFR 11.35, the FAA will post all comments received, without change, to https://www.regulations.gov,, including any personal information you provide. The agency will also post a report summarizing each substantive verbal contact received about this proposal.

Confidential Business Information

CBI is commercial or financial information that is both customarily and actually treated as private by its owner. Under the Freedom of Information Act (FOIA) (5 U.S.C. 552), CBI is exempt from public disclosure. If your comments responsive to this NPRM contain commercial or financial information that is customarily treated as private, that you actually treat as private, and that is relevant or responsive to this NPRM, it is important that you clearly designate the submitted comments as CBI. Please mark each page of your submission containing CBI as “PROPIN.” The FAA will treat such marked submissions as confidential under the FOIA, and they will not be placed in the public docket of this NPRM. Submissions containing CBI should be sent to Blaine Williams, Aviation Safety Engineer, Los Angeles ACO Branch, 3960 Paramount Boulevard, Lakewood, CA 90712-4137; telephone 562-627-5371; email blaine.willaims@faa.gov. Any commentary that the FAA receives that is not specifically designated as CBI will be placed in the public docket for this rulemaking.

Discussion

The EASA (now European Union Aviation Safety Agency), which is the Technical Agent for the Member States of the European Union, has issued EASA AD 2019-0024, dated February 4, 2019 (EASA AD 2019-0024) (also referred to as the Mandatory Continuing Airworthiness Information, or the MCAI), to correct an unsafe condition for certain Airbus Helicopters Deutschland GmbH Model BO-105A, BO-105C, BO-105D, BO-105S, and BO-105LS A-3 helicopters. Model BO-105D helicopters are not certificated by the FAA and are not included on the U.S. type certificate data sheet; this proposed AD therefore does not include those helicopters in the applicability.

This proposed AD was prompted by the FAA's determination that aging of the elastomeric material in a TT-strap could affect the structural characteristics of the TT-strap. The FAA is proposing this AD to address aging of the elastomeric material in a TT-strap, which could lead to premature failure of a TT-strap, resulting in loss of control of the helicopter. See the MCAI for additional background information.

Relationship Between This Proposed AD and AD 2016-25-14

This proposed AD would not supersede AD 2016-25-14, Amendment 39-18740 (81 FR 94944, December 27, 2016) (AD 2016-25-14). This proposed AD would require replacement of certain TT-straps with serviceable parts. Accomplishment of the proposed replacement would then terminate all of the requirements of AD 2016-25-14 for Model BO-105LS A-3 helicopters only.

Related Service Information Under 1 CFR Part 51

EASA AD 2019-0024 describes procedures for replacing certain TT-straps with serviceable parts and requires a storage life limit for TT-straps.

This material is reasonably available because the interested parties have access to it through their normal course of business or by the means identified in the ADDRESSES section.

FAA's Determination and Requirements of This Proposed AD

This product has been approved by the aviation authority of another country, and is approved for operation in the United States. Pursuant to the bilateral agreement with the State of Design Authority, the FAA has been notified of the unsafe condition described in the MCAI referenced above. The FAA is proposing this AD after evaluating all the relevant information and determining the unsafe condition described previously is likely to exist or develop in other products of the same type design.

Proposed AD Requirements

This proposed AD would require accomplishing the actions specified in EASA AD 2019-0024, described previously, as incorporated by reference, except for any differences identified as exceptions in the regulatory text of this proposed AD and except as discussed under “Differences Between this Proposed AD and the MCAI.”

Explanation of Required Compliance Information

In the FAA's ongoing efforts to improve the efficiency of the AD process, the FAA initially worked with Airbus and EASA to develop a process to use certain EASA ADs as the primary source of information for compliance with requirements for corresponding FAA ADs. The FAA has since coordinated with other manufacturers and civil aviation authorities (CAAs) to use this process. As a result, EASA AD 2019-0024 will be incorporated by reference in the FAA final rule. This proposed AD would, therefore, require compliance with EASA AD 2019-0024 in its entirety, through that incorporation, except for any differences identified as exceptions in the regulatory text of this proposed AD. Using common terms that are the same as the heading of a particular section in the EASA AD does not mean that operators need comply only with that section. For example, where the AD requirement refers to “all required actions and compliance times,” compliance with this AD requirement is not limited to the section titled “Required Action(s) and Compliance Time(s)” in the EASA AD. Service information specified in EASA AD 2019-0024 that is required for compliance with EASA AD 2019-0024 will be available on the internet at https://www.regulations.gov by searching for and locating Docket No. FAA-2021-0143 after the FAA final rule is published.

Differences Between This Proposed AD and the MCAI

Although EASA AD 2019-0024 does not specify a life limit for the Lord TT-Straps part number (P/N) J17322-1 and P/N 117-14111, this proposed AD does specify a life limit for those parts.

Where EASA AD 2019-0024 specifies that installation of a Lord TT-Strap is allowed provided the first flight of that helicopter after that installation is accomplished before the storage life of that Lord TT-Strap exceeds 5 years, for this proposed AD, the installation of a Lord TT-Strap is allowed provided the first flight of that helicopter after that installation is accomplished before 5 years since the TT-strap's date of manufacture.

Where EASA AD 2019-0024 defines “serviceable part” as a Lord TT-Strap having a storage life not exceeding 5 years, for this proposed AD, a serviceable part is Lord TT-straps P/N J17322-1 and P/N 117-14111 having less than 5 years since that TT-strap's date of manufacture.

Where EASA AD 2019-0024 specifies that the “cure date” of a TT-Strap can be determined using the information provided in the applicable service information specified in EASA AD 2019-0024, or contacting Airbus Helicopters for applicable instructions, for this proposed AD, the option of contacting Airbus Helicopters is not required.

Costs of Compliance

The FAA estimates that this proposed AD affects 61 helicopters of U.S. registry. The FAA estimates the following costs to comply with this proposed AD:

According to the manufacturer, some or all of the costs of this proposed AD may be covered under warranty, thereby reducing the cost impact on affected operators. The FAA does not control warranty coverage for affected operators. As a result, the FAA has included all known costs in the cost estimate.

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.

The FAA is 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

The FAA determined that this proposed AD would not have federalism implications under Executive Order 13132. This proposed AD would 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 proposed regulation:

(1) Is not a “significant regulatory action” under Executive Order 12866,

(2) Will not affect intrastate aviation in Alaska, 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.

List of Subjects in 14 CFR Part 39

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

The Proposed Amendment

Accordingly, under the authority delegated to me by the Administrator, the FAA proposes to amend 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.

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

Airbus Helicopters Deutschland GmbH: Docket No. FAA-2021-0143; Product Identifier 2019-SW-024-AD.

(a) Comments Due Date

The FAA must receive comments by April 26, 2021.

(b) Affected Airworthiness Directives (ADs)

This AD affects AD 2016-25-14, Amendment 39-18740 (81 FR 94944, December 27, 2016) (AD 2016-25-14).

(c) Applicability

This AD applies to Airbus Helicopters Deutschland GmbH Model BO-105A, BO-105C, BO-105S, and BO-105LS A-3 helicopters, certificated in any category, equipped with a tension torsion strap (TT-strap) as identified in European Aviation Safety Agency (now European Union Aviation Safety Agency) (EASA) AD 2019-0024, dated February 4, 2019 (EASA AD 2019-0024).

(d) Subject

Joint Aircraft System Component (JASC) Code 6200, Main Rotor System.

(e) Reason

This AD was prompted by the FAA's determination that aging of the elastomeric material in a TT-strap could affect the structural characteristics of the TT-strap. The FAA is issuing this AD to address aging of the elastomeric material in a TT-strap, which could lead to premature failure of a TT-strap, resulting in loss of control of the helicopter.

(f) Compliance

Comply with this AD within the compliance times specified, unless already done.

(g) Requirements

Except as specified in paragraph (h) of this AD: Comply with all required actions and compliance times specified in, and in accordance with, EASA AD 2019-0024.

(h) Exceptions to EASA AD 2019-0024

(1) Where EASA AD 2019-0024 refers to its effective date, this AD requires using the effective date of this AD.

(2) The “Remarks” section of EASA AD 2019-0024 does not apply to this AD.

(3) Where EASA AD 2019-0024 and the service information referenced in EASA AD 2019-0024 specify contacting Airbus Helicopters Deutschland if the storage time for a TT-strap is equal to or greater than 5 years, this AD requires repair using a method approved by the Manager, International Validation Branch, FAA. For a repair method to be approved by the Manager, International Validation Branch, as required by this paragraph, the Manager's approval letter must specifically refer to this AD.

(4) Although the service information referenced in EASA AD 2019-0024 specifies to scrap certain parts, this AD requires removing those parts from service instead.

(5) Where paragraph (1) of EASA AD 2019-0024 specifies to replace each Lord TT-Strap and Bendix TT-Strap “in accordance with the instructions of the applicable ASB,” the replacement must be done using FAA-approved procedures.

(6) Where EASA AD 2019-0024 refers to the airworthiness limitations items of the airworthiness limitations section of the aircraft maintenance manual (AMM) for the definition of service life limit (SLL), this AD requires using the life limits specified in paragraphs (h)(6)(i) through (iii) of this AD, as applicable:

(i) For Bendix TT-Strap part number (P/N) 2604067 and P/N 117-14110: Before 10 years or 40,000 flight cycles on the part, whichever occurs first.

(ii) For Bendix TT-Strap P/N 2602559 and P/N 2606576: Before 10 years, 2,400 hours time-in-service, or 40,000 flight cycles on the part, whichever occurs first.

(iii) For Lord TT-Strap P/N J17322-1 and P/N 117-14111: Before 12 years or 40,000 flight cycles on the part, whichever occurs first.

(7) Where paragraph (3) of EASA AD 2019-0024 specifies that installation of a Lord TT-Strap is allowed provided the first flight of that helicopter after that installation is accomplished before the storage life of that Lord TT-Strap exceeds 5 years, for this AD, the installation of a Lord TT-Strap is allowed provided the first flight of that helicopter after that installation is accomplished before 5 years since the TT-strap's date of manufacture.

(8) Where EASA AD 2019-0024 defines “serviceable part” as a Lord TT-Strap having a storage life not exceeding 5 years, for this AD, a serviceable part is Lord TT-straps P/N J17322-1 and P/N 117-14111 having less than 5 years since that TT-strap's date of manufacture.

(9) Where EASA AD 2019-0024 specifies that the “cure date” of a TT-Strap can be determined using the information provided in the applicable service information specified in EASA AD 2019-0024, or contacting Airbus Helicopters for applicable instructions, for this AD, the option of contacting Airbus Helicopters is not required.

(i) Repetitive Replacement

After accomplishing the replacement specified in paragraph (1) of EASA AD 2019-0024, thereafter, replace the Lord TT-straps P/N J17322-1 and P/N 117-14111, at intervals not to exceed: Before 12 years or 40,000 flight cycles on the part, whichever occurs first.

(j) Terminating Action for AD 2016-25-14

For Model B0-105LS A-3 helicopters: After accomplishing the replacement specified in paragraph (1) of EASA AD 2019-0024 all of the actions required by AD 2016-15-14 are terminated for that helicopter only.

(k) Special Flight Permit

Special flight permits, as described in 14 CFR 21.197 and 21.199, are not allowed.

(l) Alternative Methods of Compliance (AMOCs):

The Manager, International Validation Branch, FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. In accordance with 14 CFR 39.19, send your request to your principal inspector or local Flight Standards District Office, as appropriate. If sending information directly to the manager of the International Validation Branch, send it to the attention of the person identified in paragraph (m)(2) of this AD. Information may be emailed to: 9-AVS-AIR-730-AMOC@faa.gov.

(m) Related Information

(1) For EASA AD 2019-0024, contact the EASA, Konrad-Adenauer-Ufer 3, 50668 Cologne, Germany; telephone +49 221 8999 000; email ADs@easa.europa.eu; internet www.easa.europa.eu. You may find this EASA AD on the EASA website at https://ad.easa.europa.eu. You may view this material at the FAA, Office of the Regional Counsel, Southwest Region, 10101 Hillwood Pkwy, Room 6N-321, Fort Worth, TX 76177. For information on the availability of this material at the FAA, call 817-222-5110. This material may be found in the AD docket on the internet at https://www.regulations.gov by searching for and locating Docket No. FAA-2021-0143.

(2) For more information about this AD, contact Blaine Williams, Aviation Safety Engineer, Los Angeles ACO Branch, 3960 Paramount Boulevard, Lakewood, CA 90712 4137; telephone 562-627-5371; email blaine.willaims@faa.gov.