2021-19607. Airworthiness Directives; Leonardo S.p.a. Helicopters

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Supplemental notice of proposed rulemaking (SNPRM); reopening of comment period.

SUMMARY:

The FAA is revising an earlier proposal for certain Leonardo S.p.a. Model AB139 and AW139 helicopters. This action revises the notice of proposed rulemaking (NPRM) by expanding the required actions. This proposed AD would require various inspections of certain main rotor (MR) dampers, as specified in a European Aviation Safety Agency (now European Union Aviation Safety Agency) (EASA) AD, which is proposed for incorporation by reference (IBR). This proposed AD would also require reducing the torque of the MR damper hub attachment bolts, installing a special washer, installing a certain part-numbered MR damper, and prohibit installing other part-numbered MR dampers. The FAA is proposing this airworthiness directive (AD) to address the unsafe condition on these products. Since these actions would impose an additional burden over those in the NPRM, the FAA is requesting comments on this SNPRM.

DATES:

The comment period for the NPRM published in the Federal Register on March 31, 2020 (85 FR 17788), is reopened.

The FAA must receive comments on this SNPRM by October 29, 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: [phone].
• 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 [phone]; email [e-mail]; 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 [phone]. It is also available in the AD docket on the internet at https://www.regulations.gov by searching for and locating Docket No. FAA-2020-0283.

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-2020-0283; 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 SNPRM, 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:

Matt Fuller, AD Program Manager, General Aviation & Rotorcraft Unit, Airworthiness Products Section, Operational Safety Branch, FAA, 10101 Hillwood Pkwy., Fort Worth, TX 76177; telephone [phone]; email [e-mail].

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-2020-0283; Project Identifier 2018-SW-045-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 SNPRM 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 SNPRM, 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 SNPRM. Submissions containing CBI should be sent to Matt Fuller, AD Program Manager, General Aviation & Rotorcraft Unit, Airworthiness Products Section, Operational Safety Branch, FAA, 10101 Hillwood Pkwy., Fort Worth, TX 76177; telephone [phone]; email [e-mail]. Any commentary that the FAA receives that is not specifically designated as CBI will be placed in the public docket for this rulemaking.

Background

The FAA issued an NPRM to amend 14 CFR part 39 by adding an AD that would apply to certain serial-numbered Leonardo S.p.A. Model AB139 and AW139 helicopters with an MR damper part number (P/N) 3G6220V01351, 3G6220V01352, or 3G6220V01353 installed. The NPRM published in the Federal Register on March 31, 2020 (85 FR 17788). In the NPRM, the FAA proposed to require, for an affected helicopter with MR damper P/N 3G6220V01351, 3G6220V01352, or 3G6220V01353 installed, reducing the installation torque of each hub attachment bolt for each MR damper. For an affected helicopter with MR damper P/N 3G6220V01351 or 3G6220V01352 installed, the NPRM proposed to require: Repetitively inspecting the MR damper rod end (rod end) and MR damper body end (body end) for a crack; dye penetrant inspecting or eddy current inspecting certain rod and body ends for a crack; repetitively inspecting the rod and body end bearings for rotation in the damper seat and for misaligned slippage marks; repetitively inspecting the rod end broached ring nut; and repetitively inspecting the bearing friction torque value of the body and rod ends, and the MR damper anti-rotation block. Depending on the results of the various inspections, the NPRM proposed to require removing a part from service or replacing a part. For an affected helicopter with MR damper P/N 3G6220V01351 or 3G6220V01352 installed, the NPRM also proposed to require inspecting each rod end to determine if special washer P/N 3G6220A05052 is installed, and depending on the results, aligning the rod ends and broached rings, replacing any broached ring that cannot be aligned, inspecting the broached rings for wear and damage, and replacing the broached ring and installing a special washer. Lastly, the NPRM proposed to require installing MR damper P/N 3G220V01353, prohibit installing MR damper P/N 3G6220V01351 and P/N 3G6220V01352 on any helicopter, and allow the installation of MR damper P/N 3G220V01353 to constitute terminating action for all of the proposed repetitive required actions.

The NPRM was prompted by EASA AD 2018-0112R1, dated June 4, 2018 (EASA AD 2018-0112R1), which is the most recent of a series of ADs issued by EASA, the Technical Agent for the Member States of the European Union, to correct an unsafe condition for certain Leonardo S.p.A. Helicopters (formerly Finmeccanica S.p.A., Helicopter Division (FHD), AgustaWestland S.p.A., Agusta S.p.A.), AgustaWestland Philadelphia Corporation (formerly Agusta Aerospace Corporation) Model AB139 and AW139 helicopters. EASA advises of multiple failures of MR damper P/Ns 3G6220V01351 and 3G6220V01352. EASA states that in some cases these failures occurred at the eye end and body lugs resulting in disconnection of the MR damper in-flight. EASA further states that a combination of factors, including cracks on the MR damper rod end and body end and in-service failure of the eye end and body lugs may have contributed to the MR damper disconnections. Information issued by Leonardo Helicopters advises of MR damper cracking, loose rod ends, bearing rotation in the damper seat, and damage, incorrect engagement, and misalignment of the lag damper broached ring nut, particularly the broached ring teeth and the damper piston slots.

EASA states that this condition could result in loss of the lead-lag damping function of the MR blade, damage to adjacent critical rotor components, and subsequent reduced control of the helicopter. Accordingly, EASA AD 2018-0112R1 requires various one-time and repetitive inspections of the MR damper, a torque check of the damper body end, and replacing any MR damper with a crack or that fails the torque check. EASA AD 2018-0112R1 also requires replacing MR damper P/N 3G6220V01351 and 3G6220V01352 with P/N 3G220V01353, as additional tests determined that MR damper P/N 3G220V01353 does not need to be subject to inspections for cracks, provided it is removed from service before it reaches its retirement life.

Actions Since the NPRM Was Issued

Since the NPRM was issued, the FAA identified an action required by EASA AD 2018-0112R1 that was inadvertently omitted in the NPRM and incorrect thresholds for different actions proposed in the NPRM. The NPRM omitted the one-time dye penetrant inspection for any MR dampers that have accumulated 300 or more total hours time-in-service (TIS). The NPRM also stated incorrect thresholds to inspect each rod end bearing and body end bearing for rotation. The NPRM proposed to require those inspections based on the total hours TIS accumulated by the MR damper, when the thresholds for those inspections should have been based on the total hours TIS accumulated by the rod end and body end, independently. This SNPRM makes those updates.

The NPRM also inadvertently omitted the option to accomplish an eddy current inspection for some inspections. This SNPRM adds that alternative for those inspections.

Lastly, this SNPRM utilizes the FAA's new practice of proposing to incorporate EASA AD 2018-0112R1 by reference.

Comments

The FAA gave the public the opportunity to participate in developing this proposed AD. The FAA has considered the comment received.

Request To Reduce the Applicability

One commenter requested removing MR damper P/N 3G6220V01353 from the applicability. The commenter stated that the only requirement in this AD for that P/N is to reduce the torque on the body end of the MR damper and that procedures for this are available in the Interactive Electronic Technical Publications (IETP). The commenter asked if the intent is to capture any MR damper P/N 3G6220V01353 installed prior to the current IETP revisions with an incorrect torque. The commenter further stated that part II of Leonardo Helicopters Alert Service Bulletin No. 139-452, Revision B, dated April 10, 2018 (ASB 139-452 Rev B), is not applicable to MR damper P/N 3G6220V01353.

The FAA disagrees. The commenter is correct that part II of ASB 139-452 Rev B is not applicable to MR damper P/N 3G6220V01353; however, part I of ASB 139-452 Rev B, which specifies procedures to reduce the torque of the nut on the bolt attaching each MR damper to the MR hub, is applicable to MR damper P/N 3G6220V01353. Additionally, the FAA appreciates that while the procedures to reduce that torque may now be available in the IETP, not all operators are required to accomplish manufacturer's maintenance procedures. Where the FAA has determined that procedures, including manufacturer's maintenance procedures, are necessary to correct an unsafe condition, the FAA must issue an AD.

FAA's Determination

These products have been approved by the aviation authority of another country, and are 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 EASA AD 2018-0112R1 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 these same type designs.

Certain changes described above expand the scope of the NPRM. As a result, the FAA has determined that it is necessary to reopen the comment period to provide additional opportunity for the public to comment on this SNPRM.

Related Service Information Under 1 CFR Part 51

EASA AD 2018-0112R1 requires reducing the installation torque of the bolts affixing each affected MR damper to the MR hub. For certain affected MR dampers, EASA AD 2018-0112R1 requires a one-time dye penetrant inspection of the rod and body ends, and a repetitive detailed visual inspection of the rod and body ends. EASA AD 2018-0112R1 allows an eddy current inspection as an alternative to those inspections. For certain affected MR dampers, EASA AD 2018-0112R1 also requires repetitively inspecting the rod and body end bearings for rotation, visually inspecting the rod end broached ring nut, accomplishing a bearing friction inspection of the body and rod end bearings, and a detailed inspection of the anti-rotation block. EASA AD 2018-0112R1 also requires a one-time visual inspection of certain affected MR damper rod end installations and a torque check of the MR damper broached ring nut. For certain affected MR dampers, EASA AD 2018-0112R1 requires replacing any special washer P/N 3G6220A05051 with a new washer P/N 3G6220A05052. If there is a crack or damage detected in any inspection, EASA AD 2018-0112R1 requires contacting Leonardo and, if the discrepancy is confirmed, replacing the MR damper. EASA AD 2018-0112R1 also requires corrective actions if any discrepancy is detected in the inspections for rotation, friction, and torque. EASA AD 2018-0112R1 allows installing MR damper P/N 3G6220V01353 on a helicopter, provided that it is installed using the correct torque values. Lastly, EASA AD 2018-0112R1 prohibits installing MR damper P/N 3G6220V01351 and P/N 3G6220V01352 on any helicopter.

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.

Proposed AD Requirements of This SNPRM

This proposed AD would require accomplishing the actions specified in EASA AD 2018-0112R1, described previously, as incorporated by reference, except for any differences identified as exceptions in the regulatory text of this AD and except as discussed under “Differences Between this Proposed AD and the EASA AD.”

Explanation of Required Compliance Information

In the FAA's ongoing efforts to improve the efficiency of the AD process, the FAA developed a process to use some civil aviation authority (CAA) ADs as the primary source of information for compliance with requirements for corresponding FAA ADs. The FAA has been coordinating this process with manufacturers and CAAs. As a result, the FAA proposes to incorporate EASA AD 2018-0112R1 by reference in the FAA final rule. This proposed AD would, therefore, require compliance with EASA AD 2018-0112R1 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 EASA AD 2018-0112R1 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 EASA AD 2018-0112R1. Service information referenced in EASA AD 2018-0112R1 for compliance will be available at https://www.regulations.gov by searching for and locating Docket No. FAA-2020-0283 after the FAA final rule is published.

Differences Between This Proposed AD and the EASA AD

Where EASA AD 2018-0112R1 requires the compliance time of after the last flight (ALF) of the day inspection, this proposed AD would require the compliance time of before the first flight of the day. Some compliance times in EASA AD 2018-0112R1 are on condition of part removal or replacement, whereas this proposed AD would not include those compliance times. EASA AD 2018-0112R1 requires a torque check of the MR damper broached ring nut, whereas this proposed AD would require a torque inspection instead to clarify that the action must be accomplished by a mechanic that meets the requirements of 14 CFR part 65 subpart D. EASA AD 2018-0112R1 requires making sure that there are no scratches or dents on the rod end, however it does not state corrective action for this requirement; this proposed AD would require removing the rod end from service if there is a scratch or dent on the rod end. Where EASA AD 2018-0112R1 requires contacting Leonardo and replacing the MR damper with a serviceable part, this proposed would require replacing or removing parts from service instead. Where EASA AD 2018-0112R1 requires accomplishing applicable corrective action(s) as specified in, and in accordance with, the instructions in service information, this proposed AD would require removing parts from service for some of the corrective actions instead. Where EASA AD 2018-0112R1 requires a one-time dye penetrant inspection of certain rod ends when installed, this proposed AD would not. Instead, this proposed AD would prohibit installing certain rod ends that are not marked with a black dot and therefore have not been inspected.

Costs of Compliance

The FAA estimates that this AD, if adopted as proposed, would affect 126 helicopters of U.S. Registry. Labor rates are estimated at $85 per work-hour. Based on these numbers, the FAA estimates the following costs to comply with this proposed AD.

Performing the MR damper inspections would take about 24 work-hours, for an estimated cost of $2,040 per helicopter and $257,040 for the U.S. fleet, per inspection cycle.

Replacing a rod end would take about 3 work-hours and parts would cost about $500, for an estimated cost of $755 per rod end. Replacing a broached ring and broached ring nut would take about 3 work-hours and parts would cost about $125, for an estimated cost of $380 per broached ring and broached ring nut. Replacing an anti-rotation block would take about 3 work-hours and parts would cost about $50, for an estimated cost of $305 per anti-rotation block. Replacing an MR damper would take about 2 work-hours and parts would cost about $18,000, for an estimated cost of $18,170 per MR damper.

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) Would not affect intrastate aviation in Alaska, and

(3) Would 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.

§ 39.13

[Amended]

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

Leonardo S.p.a.: Docket No. FAA-2020-0283; Project Identifier 2018-SW-045-AD.

(a) Comments Due Date

The FAA must receive comments by October 29, 2021.

(b) Affected ADs

None.

(c) Applicability

This AD applies to Leonardo S.p.a. Model AB139 and AW139 helicopters, certificated in any category, as identified in European Aviation Safety Agency (now European Union Aviation Safety Agency) (EASA) AD 2018-0112R1, dated June 4, 2018 (EASA AD 2018-0112R1).

(d) Subject

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

(e) Unsafe Condition

This AD was prompted by reports of failed main rotor (MR) dampers. The FAA is issuing this AD to address a crack in an MR damper. The unsafe condition, if not addressed, could result in seizure of the MR damper, detachment of the MR damper in-flight, and subsequent 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 2018-0112R1.

(h) Exceptions to EASA AD 2018-0112R1

(1) Where EASA AD 2018-0112R1 requires compliance in terms of flight hours (FH), this AD requires using hours time-in-service (TIS).

(2) Where EASA AD 2018-0112R1 refers to FH accumulated by a part since new (first installation on a helicopter) or since overhaul, this AD requires using total hours TIS.

(3) Where EASA AD 2018-0112R1 refers to its effective date; May 10, 2016 (the effective date of EASA AD 2016-0087, dated May 3, 2016); July 28, 2016 (the effective date of EASA AD 2016-0140, dated July 14, 2016); or September 11, 2017 (the effective date of EASA AD 2017-0160, dated August 28, 2017), this AD requires using the effective date of this AD.

(4) Where EASA AD 2018-0112R1 requires the compliance time of during an “after the last flight (ALF) of the day inspection,” this AD requires the compliance time of before the first flight of the day.

(5) Where the service information referenced in EASA AD 2018-0112R1 specifies using a magnifying glass, this AD requires using a 5X or higher power magnifying glass.

(6) Where the service information referenced in EASA AD 2018-0112R1 specifies discarding parts, this AD requires removing those parts from service.

(7) Where paragraph (2) of EASA AD 2018-0112R1 requires compliance within 30 FH after 10 May 2016 (the effective date of EASA AD 2016-0087, dated May 3, 2016), or at the first MR damper removal, whichever occurs first, for a MR damper that has accumulated 300 or more FH, this AD requires compliance within 30 hours TIS after the effective date of this AD for a MR damper that has accumulated 300 or more total hours TIS.

(8) This AD does not require the actions required by paragraph (3) of EASA AD 2018-0112R1.

(9) Where paragraph (8) of EASA AD 2018-0112R1 refers to having a serial number (S/N) specified in Part V of FHD BT 139-450, this AD requires the actions of that paragraph for helicopters with an MR damper part number (P/N) 3G6220V01351 or 3G6220V01352 with an S/N up to MCR8086 inclusive, installed, that has accumulated less than 600 total hours TIS.

(10) Where paragraph (10) of EASA AD 2018-0112R1 refers to having an S/N specified in in Part VII of FHD BT 139-450, this AD requires the actions of that paragraph for helicopters with:

(i) MR damper P/N 3G6220V01351 or 3G6220V01352 with an S/N up to MCR8764 inclusive, and with rod end P/N M006-01H004-041, -045, or -053, installed, except MR dampers confirmed of having 60-80 Nm applied and MR dampers marked with “BT 139-446 Part II” or “BT 139-446 Part III” on the logcard; or

(ii) MR damper P/N 3G6220V01351 or 3G6220V01352 that has had the damper rod end assembly removed before the issuance of “BT 139-446” installed, even if it has an S/N higher than MCR8764 or it has been confirmed of having 60-80 Nm applied.

Note 1 to paragraph (h)(10):

MR dampers confirmed of having 60-80 Nm applied are listed in Table 1 (two pages) of Annex A, of Leonardo Helicopters Alert Service Bulletin No. 139-450, Revision D, dated May 28, 2019.

(11) Where paragraph (10) of EASA AD 2018-0112R1 requires a torque check, this AD requires a torque inspection.

(12) Where the service information referenced in paragraph (10) of EASA AD 2018-0112R1 specifies making sure that there are not scratches or dents on the rod end, this AD requires, before further flight, removing the rod end from service if there is a scratch or dent on the rod end.

(13) Where paragraph (12) of EASA AD 2018-0112R1 requires contacting Leonardo and replacing the MR damper with a serviceable part, this AD does not. This AD requires the following:

(i) If there is a crack in an MR damper body end, before further flight, replace the MR damper.

(ii) If there is a crack in an MR damper rod end, before further flight, remove the MR damper rod end from service.

(iii) If there is damage in any teeth of a rod end broached ring nut or damper piston slot, or if the engagement or alignment is not correct, before further flight, remove the rod end broached ring nut from service.

(14) Paragraph (13) of EASA AD 2018-0112R1 requires accomplishing the applicable corrective action(s) as specified in, and in accordance with, the instructions of FHD BT 139-450 or FHD BT 139-452, as applicable, except where:

(i) If there is any bearing seat rotation or misaligned slippage mark in the MR damper rod end, this AD requires, before further flight, removing the MR damper rod end from service.

(ii) If the MR damper rod end torque value is more than 30.0 Nm (265.5 in lb), this AD requires, before further flight, removing the MR damper rod end from service.

(iii) If any MR damper anti-rotation block dimension measurement exceeds allowable limits, this AD requires, before further flight, removing the anti-rotation block from service.

(15) This AD does not mandate compliance with the “Remarks” section of EASA AD 2018-0112R1.

(i) Parts Prohibition

As of the effective date of this AD, do not install an MR damper rod end P/N M006-01H004-041, M006-01H004-045, or M006-01H004-053 on any helicopter, unless it is marked with a black dot indicating that it has passed inspections specified by Leonardo Helicopters BT 139-450.

(j) No Reporting Requirement

Although the service information referenced in EASA AD 2018-0112R1 specifies to submit certain information to the manufacturer, this AD does not include that requirement.

(k) Alternative Methods of Compliance (AMOCs)

(1) 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 (l)(2) of this AD. Information may be emailed to: [e-mail].

(2) Before using any approved AMOC, notify your appropriate principal inspector, or lacking a principal inspector, the manager of the local flight standards district office/certificate holding district office.

(l) Related Information

(1) For EASA AD 2018-0112R1, contact EASA, Konrad-Adenauer-Ufer 3, 50668 Cologne, Germany; telephone [phone]; email [e-mail]; internet www.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 [phone]. This material may be found in the AD docket at https://www.regulations.gov by searching for and locating Docket No. FAA-2020-0283.

(2) For more information about this AD, contact Matt Fuller, AD Program Manager, General Aviation & Rotorcraft Unit, Airworthiness Products Section, Operational Safety Branch, FAA, 10101 Hillwood Pkwy., Fort Worth, TX 76177; telephone [phone]; email [e-mail].

Issued on September 7, 2021.

Lance T. Gant,

Director, Compliance & Airworthiness Division, Aircraft Certification Service.