2023-24328. Airworthiness Directives; Diamond Aircraft Industries GmbH Airplanes

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

The FAA proposes to supersede Airworthiness Directive (AD) 2022–21–15, which applies to certain Diamond Aircraft Industries GmbH (DAI) Model DA 42, DA 42 NG, and DA 42 M–NG airplanes. AD 2022–21–15 requires replacing the rudder T-yoke axle with an improved rudder T-yoke axle. Since the FAA issued AD 2022–21–15, the European Union Aviation Safety Agency (EASA) superseded its mandatory continuing airworthiness information (MCAI) to correct an unsafe condition on these products. This proposed AD would require, for certain airplanes, inspecting the rudder steering bracket edge distance and depending on the inspection results, inspecting the T-yoke bolt hole for wear and play, and corrective action if necessary. For certain airplanes this proposed AD would require replacing the rudder T-yoke bolt (axle) with a serviceable part, and applying torque seal marks on the rudder T-yoke bolt head, and self-locking nut. For all airplanes this proposed AD would require repetitively inspecting the torque seal marks on the rudder T-yoke bolt head for proper alignment and the self-locking nut for proper installation and corrective action if necessary. This proposed AD would also prohibit the installation of affected parts. The FAA is proposing this AD to address the unsafe condition on these products.

DATES:

The FAA must receive comments on this NPRM by December 26, 2023.

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 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.

AD Docket: You may examine the AD docket at regulations.gov under Docket No. FAA–2023–2143; 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, the MCAI, any comments received, and other information. The street address for Docket Operations is listed above.

Material Incorporated by Reference:

• For service information identified in this NPRM, contact Diamond Aircraft Industries GmbH, N.A. Otto-Straße 5, A–2700 Wiener Neustadt, Austria; phone: [phone]; email: [e-mail]; website: diamondaircraft.com.

• You may view this service information at the FAA, Airworthiness Products Section, Operational Safety Branch, 901 Locust, Kansas City, MO 64106. For information on the availability of this material at the FAA, call (817) 222–5110. It is also available at regulations.gov under Docket No. FAA–2023–2143.

FOR FURTHER INFORMATION CONTACT:

Penelope Trease, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; phone: [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–2023–2143; Project Identifier MCAI–2023–00088–A” 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 the 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 regulations.gov, including any personal information you provide. The agency will also post a report summarizing each substantive verbal contact received about this NPRM.

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: Penelope Trease, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590. Any commentary that the FAA receives which is not specifically designated as CBI will be placed in the public docket for this rulemaking.

Background

The FAA issued AD 2022–21–15, Amendment 39–22214 (87 FR 67541, November 9, 2022) (AD 2022–21–15), for certain DAI Model DA 42, DA 42 NG, and DA 42 M–NG airplanes. AD 2022–21–15 was prompted by MCAI originated by EASA, which is the Technical Agent for the Member States of the European Union. EASA issued EASA AD 2019–0302, dated December 13, 2019 (EASA AD 2019–0302) to correct an unsafe condition on DAI Model DA 42, DA 42 NG, and DA 42 M–NG airplanes. EASA AD 2019–0302 described the unsafe condition as reports of a loose rudder T-yoke axle nut on DAI Model DA 42 airplanes and the need for new inspections for correct installation of the self-locking nut to the rudder T-yoke standard bolt LN 9037 (dimensions M6x90), and depending on findings, accomplishment of applicable corrective action(s) and replacement of the self-locking nut. EASA AD 2019–0302 also provided an optional terminating action for the repetitive inspections. This condition, if not detected and corrected, could lead to vertical movement of the bolt, possibly resulting in reduced rudder control of the airplane.

AD 2022–21–15 requires replacing the rudder T-yoke axle with an improved rudder T-yoke bolt. The FAA issued AD 2022–21–15 to prevent movement of the T-yoke bolt.

Actions Since AD 2022–21–15 Was Issued

Since the FAA issued AD 2022–21–15, EASA superseded EASA AD 2019–0302 and issued EASA AD 2023–0013, dated January 18, 2023 (EASA AD 2023–0013) (referred to after this as the MCAI) to correct an unsafe condition on all DAI Model DA 42, DA 42 M, DA 42 NG, and DA 42 M–NG airplanes.

The MCAI states that since EASA AD 2019–0302 was issued, DAI published revised service information to provide additional inspection and modification instructions. The MCAI requires a one-time inspection of the rudder steering bracket for insufficient edge distance or wear, replacement of rudder T-yoke standard bolt LN 9037 (dimensions M6x90) with rudder T-yoke bolt part number (P/N) D60–5320–00–32, repetitive inspections of rudder T-yoke bolt P/N D60–5320–00–32 for correct installation, corrective actions if necessary, and prohibits installation of rudder T-yoke standard bolt LN 9037 (dimensions M6x90). The affected and serviceable parts, identified as “bolt” in EASA AD 2023–0013, were referred to as “axle” in EASA AD 2019–0302.

This condition, if not detected and corrected, could lead to blockage or loss of rudder control. You may examine the MCAI in the AD docket at regulations.gov under Docket No. FAA–2023–2143.

Related Service Information Under 1 CFR Part 51

The FAA reviewed Diamond Aircraft Mandatory Service Bulletin DAI MSB 42–143/1 and DAI MSB 42NG–086/1, dated January 25, 2022 (issued as one document), published with DAI Work Instruction WI–MSB 42–143 and WI–MSB 42NG–086, Revision 3, dated November 15, 2022 (issued as one document) attached. The service bulletin specifies compliance with the work instruction, which contains procedures for inspecting the hole position and condition in the rudder steering bracket.

The FAA also reviewed Diamond Aircraft Recommended Service Bulletin DAI RSB 42–139 and DAI RSB 42NG–081, dated October 21, 2019 (issued as one document), published with DAI Work Instruction WI–RSB 42–139 and WI–RSB 42NG–081, Revision 2, dated November 15, 2022 (issued as one document) attached. The service bulletin specifies compliance with the work instruction, which contains procedures for replacement of the rudder T-yoke axle with an improved (additional retaining pin) rudder T-yoke axle.

In addition, the FAA reviewed Diamond Aircraft Mandatory Service Bulletin DAI MSB 42–146 and DAI MSB 42NG–087, dated November 15, 2022, (issued as one document). The service bulletin specifies the serial numbers for airplanes identified as Group 2 in the requirements of this proposed AD. This service information is reasonably available because the interested parties have access to it through their normal course of business or by the means identified in ADDRESSES .

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 FAA's bilateral agreement with this State of Design Authority, it has notified the FAA of the unsafe condition described in the MCAI and service information described above. The FAA is issuing this NPRM after determining that the unsafe condition described previously is likely to exist or develop on other products of the same type design.

Proposed AD Requirements in This NPRM

This proposed AD would retain the requirement of AD 2022–21–15 to replace rudder T-yoke axle part number P/N LN 9037–M6x90 with rudder T-yoke axle P/N D60–5320–00–32. This proposed AD would require, for certain airplanes, inspecting the rudder steering bracket edge distance and depending on the inspection results, inspecting the T-yoke bolt hole for wear and play, and corrective actions if necessary. For certain airplanes, this proposed AD would also require applying torque seal marks on the T-yoke bolt head and self-locking nut. For all airplanes, this proposed AD would require repetitively inspecting the torque seal marks on the T-yoke bolt head for proper alignment, and the self-locking nut for proper installation, and corrective action if necessary. This proposed AD would also prohibit the installation of affected parts.

Differences Between This Proposed AD and the MCAI

The MCAI applies to DAI Model DA 42 M airplanes and this proposed AD does not because those airplanes do not have an FAA type certificate.

Paragraph (3) of the MCAI specifies to contact the manufacturer for repair instructions and paragraph (7) of the MCAI specifies to contact the manufacturer for corrective actions if any discrepancy is found, but for both of those corrective actions, this proposed AD would require contacting either the Manager, International Validation Branch, FAA; EASA; or Diamond's EASA Design Organization Approval (DOA) instead. If approved by the DOA, the approval must include the DOA-authorized signature.

Costs of Compliance

The FAA estimates that this AD, if adopted as proposed, would affect 205 airplanes of U.S. registry.

The FAA estimates the following costs to comply with this proposed AD:

Estimated Costs

Action	Labor cost	Parts cost	Cost per product	Cost on U.S. operators
Inspection of rudder steering bracket edge distance	0.25 work-hour × $85 per hour = $21.25	$0	$21.25	$4,356.25.
Replacement of rudder t-yoke bolt P/N LN 9037 with P/N D60–5320–0032	0.50 work-hour × $85 per hour = $42.50	82	$124.50	$25,522.50.
Application of torque seal marks to rudder T-yoke bolt and self-locking nut	0.75 work-hour × $85 per hour = $63.75	15	$78.75	$16,143.75.
Repetitive inspection of torque seal marks	0.25 work-hour × $85 per hour	0	$21.25, per inspection	$4,356.25, per inspection.

On-Condition Costs

Action	Labor cost	Parts cost	Cost per product
Inspection of rudder steering bracket hole for wear and play, if edge distance is equal to or greater than 11 millimeters	0.50 work-hour × $85 per hour = $42.50	$0	$42.50

Since the replacement or repair instructions could vary significantly from airplane to airplane if discrepancies are found during the inspections, the FAA has no data to determine the number of airplanes that would need follow-on actions or what the cost per airplane would be.

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 that the 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:

a. Removing Airworthiness Directive 2022–21–15, Amendment 39–22214 ( 87 FR 67541, November 9, 2022); and

b. Adding the following new airworthiness directive:

Diamond Aircraft Industries GmbH: Docket No. FAA–2023–2143; Project Identifier MCAI–2023–00088–A.

(a) Comments Due Date

The FAA must receive comments on this airworthiness directive (AD) by December 26, 2023.

(b) Affected ADs

This AD replaces AD 2022–21–15, Amendment 39–22214 (87 FR 67541, November 9, 2022).

(c) Applicability

This AD applies to Diamond Aircraft Industries GmbH (DAI) Model DA 42, DA 42 NG, and DA 42 M–NG airplanes, all serial numbers, certificated in any category.

(d) Subject

Joint Aircraft System Component (JASC) Code 2700, Flight Control System.

(e) Unsafe Condition

This AD was prompted by reports of a loose rudder T-yoke bolt nut, excessive wear of the hole, and insufficient hole edge margin at the rudder steering bracket. The FAA is issuing this AD to detect and correct vertical movement of the T-yoke bolt (axle). The unsafe condition, if not addressed, could lead to blockage or loss of rudder control and result in reduced control of the airplane.

(f) Compliance

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

(g) Definitions

For the purposes of this AD, the following definitions apply.

(1) Group 1 airplanes: Airplanes with serial numbers specified in Technical Details, section I.2, of Diamond Aircraft Mandatory Service Bulletin DAI MSB 42–143/1 and DAI MSB 42NG–086/1, dated January 25, 2022 (issued as one document), published with DAI Work Instruction WI–MSB 42–143 and WI–MSB 42NG–086, Revision 3, dated November 15, 2022 (issued as one document) attached.

(2) Group 2 airplanes: Airplanes with serial numbers specified in Technical Details, section I.2, of Diamond Aircraft Mandatory Service Bulletin DAI MSB 42–146 and DAI MSB 42NG–087, dated November 15, 2022, (issued as one document).

(3) Group 3 airplanes: Airplanes that are not in Group 1 or Group 2.

(4) Depending on the serial number, a Group 1 airplane can also be a Group 2 airplane.

(h) Inspections and Corrective Actions

For Group 1 and Group 2 airplanes: Do the inspection required by paragraph (h)(1) of this AD at the compliance time specified in paragraph (h)(1) of this AD and the applicable corrective actions specified in paragraphs (h)(2) through (4) of this AD at the applicable compliance times specified in paragraphs (h)(2) through (4) of this AD.

(1) Within 200 hours time-in-service (TIS) or 9 months after the effective date of this AD, whichever occurs first, inspect the rudder steering bracket edge distance by measuring in accordance with step 6 of the Instructions, Section III, in Diamond Aircraft Work Instruction WI–MSB 42–143 and WI–MSB 42NG–086, Revision 3, dated November 15, 2022 (issued as one document) attached to Diamond Aircraft Mandatory Service Bulletin DAI MSB 42–143/1 and DAI MSB 42NG–086/1, dated January 25, 2022 (issued as one document).

(2) If, during the inspection required by paragraph (h)(1) of this AD, the measured distance is equal to or greater than 11 millimeters (mm), before further flight, inspect the hole in the rudder steering bracket for wear and play in accordance with step 11 of the Instructions, Section III, in Diamond Aircraft Work Instruction WI–MSB 42–143 and WI–MSB 42NG–086, Revision 3, dated November 15, 2022 (issued as one document) attached to Diamond Aircraft Mandatory Service Bulletin DAI MSB 42–143/1 and DAI MSB 42NG–086/1, dated January 25, 2022 (issued as one document).

(3) If, during the inspection required by paragraph (h)(1) of this AD, the measured distance is less than 11 mm, before further flight, contact the Manager, International Validation Branch, FAA; the European Union Aviation Safety Agency (EASA); or Diamond's EASA Design Organization Approval (DOA) for repair instructions, and within the compliance time specified therein, complete the repair. If approved by the DOA, the approval must include the DOA-authorized signature.

(4) If, during the inspection required by paragraph (h)(2) of this AD, a worn or enlarged hole is found on the rudder steering bracket, or if the T-yoke bolt is found to have play, before further flight, contact the Manager, International Validation Branch, FAA; EASA; or Diamond's EASA DOA for instructions (repair or replacement of the rudder steering bracket), and within the compliance time specified therein, do the instructions. If approved by the DOA, the approval must include the DOA-authorized signature.

(i) Replacement

For Group 2 airplanes: Concurrently with the inspection required by paragraph (h)(1) of this AD, replace the rudder T-yoke bolt part number (P/N) LN 9037–M6x90 with rudder T-yoke bolt P/N D60–5320–00–32, and apply torque seal marks on the rudder T-yoke bolt head and self-locking nut, in accordance with steps 14, 15, and 18 of the Instructions, Section III, in Diamond Aircraft Work Instruction WI–RSB 42–139 and WI–RSB 42NG–081, Revision 2, dated November 15, 2022 (issued as one document) attached to Diamond Aircraft Recommended Service Bulletin DAI RSB 42–139 and DAI RSB 42NG–081, dated October 21, 2019 (issued as one document).

(j) Repetitive Inspections

(1) For Group 1 and Group 2 airplanes: Within 200 hours TIS after the inspection required by paragraph (h)(1) of this AD and, thereafter, at intervals not to exceed 200 hours TIS, inspect the torque seal marks on the T-yoke bolt head and self-locking nut for proper alignment.

Note 1 to paragraph (j)(1): This can be accomplished using DAI Maintenance Manual (AMM) Temporary Revision (TR) AMM–TR–MÄM–42–1213/a, dated June 7, 2022 (DAI AMM TR AMM–TR–MÄM–42–1213/a).

(2) For Group 3 airplanes: Within 200 hours TIS after the effective date of this AD, and thereafter at intervals not to exceed 200 hours TIS, inspect the torque seal marks on the T-yoke bolt head and self-locking nut for proper alignment.

Note 2 to paragraph (j)(2): This can be accomplished using DAI AMM TR AMM–TR–MÄM–42–1213/a.

(3) For all airplanes: If, during any inspection required by paragraph (j)(1) or (j)(2) of this AD, it is found that the torque seal marks are not properly aligned, before further flight, contact the Manager, International Validation Branch, FAA; EASA; or Diamond's EASA DOA for approved repair instructions, and within the compliance time specified therein, accomplish those instructions accordingly. If approved by the DOA, the approval must include the DOA-authorized signature.

(k) Parts Installation Prohibition

For all airplanes: As of the effective date of this AD, do not install on any airplane a rudder T-yoke bolt P/N LN 9037–M6x90.

(l) Credit for Previous Actions

(1) You may take credit for the actions required by paragraphs (h)(1) and (2) of this AD if the actions were done before the effective date of this AD using any of the work instructions specified in paragraphs (l)(1)(i), (ii), or (iii) of this AD.

(i) Diamond Aircraft Work Instruction WI–MSB 42–143 and WI–MSB 42NG–086, Revision 0, dated December 23, 2021 (issued as one document) attached to Diamond Aircraft Mandatory Service Bulletin DAI MSB 42–143 and DAI MSB 42NG–086, dated December 23, 2021 (issued as one document).

(ii) Diamond Aircraft Work Instruction WI–MSB 42–143 and WI–MSB 42NG–086, Revision 1, dated January 25, 2022 (issued as one document) attached to Diamond Aircraft Mandatory Service Bulletin DAI MSB 42–143/1 and DAI MSB 42NG–086/1, dated January 25, 2022 (issued as one document).

(iii) Diamond Aircraft Work Instruction WI–MSB 42–143 and WI–MSB 42NG–086, Revision 2, dated March 10, 2022 (issued as one document) attached to Diamond Aircraft Mandatory Service Bulletin DAI MSB 42–143/1 and DAI MSB 42NG–086/1, dated January 25, 2022 (issued as one document).

(2) You may take credit for the rudder T-yoke bolt replacement required by paragraph (i) of this AD if that action was done before the effective date of this AD using the Diamond Aircraft Work Instruction WI–RSB 42–139 and WI–RSB 42NG–081, Revision 1, dated October 24, 2019 (issued as one document) attached to Diamond Aircraft Recommended Service Bulletin DAI RSB 42–139 and DAI RSB 42NG–081, dated October 21, 2019 (issued as one document).

(m) 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 International Validation Branch, send it to the attention of the person identified in paragraph (n)(2) of this AD or email to: [e-mail]. If mailing information, also submit information by email. Before using any approved AMOC, notify your appropriate principal inspector, or lacking a principal inspector, the manager of the responsible Flight Standards Office.

(n) Additional Information

(1) Refer to EASA AD 2023–0013, dated January 18, 2023, for related information. This EASA AD may be found in the AD docket at regulations.gov under Docket No. FAA–2023–2143.

(2) For more information about this AD, contact Penelope Trease, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; phone: [phone]; email: [e-mail].

(3) Service information identified in this AD that is not incorporated by reference is available at the addresses specified in paragraphs (o)(3) and (4) of this AD.

(o) Material Incorporated by Reference

(1) The Director of the Federal Register approved the incorporation by reference (IBR) of the service information listed in this paragraph under 5 U.S.C. 552(a) and 1 CFR part 51.

(2) You must use this service information as applicable to do the actions required by this AD, unless the AD specifies otherwise.

(i) Diamond Aircraft Mandatory Service Bulletin DAI MSB 42–143/1 and DAI MSB 42NG–086/1, dated January 25, 2022 (issued as one document), published with DAI Work Instruction WI–MSB 42–143 and WI–MSB 42NG–086, Revision 3, dated November 15, 2022 (issued as one document) attached.

(ii) Diamond Aircraft Mandatory Service Bulletin DAI MSB 42–146 and DAI MSB 42NG–087, dated November 15, 2022, (issued as one document).

(iii) Diamond Aircraft Recommended Service Bulletin DAI RSB 42–139 and DAI RSB 42NG–081, dated October 21, 2019 (issued as one document), published with DAI Work Instruction WI–RSB 42–139 and WI–RSB 42NG–081, Revision 2, dated November 15, 2022 (issued as one document) attached.

(3) For service information identified in this AD, contact Diamond Aircraft Industries GmbH, N.A. Otto-Straße 5, A–2700 Wiener Neustadt, Austria; phone: [phone]; email: [e-mail]; website: diamondaircraft.com.

(4) You may view this service information at the FAA, Airworthiness Products Section, Operational Safety Branch, 901 Locust, Kansas City, MO 64106. For information on the availability of this material at the FAA, call (817) 222–5110. It is also available at regulations.gov under Docket No. FAA–2023–2143.

(5) You may view this material at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, visit www.archives.gov/​federal-register/​cfr/​ibr-locations or email [e-mail].

Issued on October 30, 2023.

Ross Landes,

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