2024-05477. Airworthiness Directives; Textron Aviation Inc. (Type Certificate Previously Held by Cessna Aircraft Company) Airplanes

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

The FAA proposes to adopt a new airworthiness directive (AD) for Textron Aviation Inc. (Textron) (type certificate previously held by Cessna Aircraft Company) Model 525, 525A, and 525B airplanes with Tamarack active technology load alleviation system (ATLAS) winglets installed per Supplemental Type Certificate (STC) No. SA03842NY. This proposed AD was prompted by a report of an un-annunciated failure of the ATLAS system. This proposed AD would require installing placards on the left-hand inboard edge of the Tamarack active camber surface (TACS) and revising the existing airplane flight manual (AFM) for your airplane. 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 May 6, 2024.

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–2024–0470; 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.

Material Incorporated by Reference:

• For material identified in this NPRM, contact Tamarack Aerospace Group, Inc., 2021 Industrial Drive, Sandpoint, ID 83864; phone: [phone]; website: tamarackaero.com/customer-support.

• You may view this material 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.

FOR FURTHER INFORMATION CONTACT:

Anthony Caldejon, Aviation Safety Engineer, FAA, 3960 Paramount Boulevard, Lakewood, CA 90712; 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–2024–0470; Project Identifier AD–2023–00694–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 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 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 Anthony Caldejon, Aviation Safety Engineer, FAA, 3960 Paramount Boulevard, Lakewood, CA 90712. 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 received a report that, while accomplishing a reliability improvement program, Tamarack discovered the potential for a failure of the ATLAS system in which a loss of load alleviation would be un-annunciated. The manufacturer's investigation revealed that failure of either of one of a pair of opto-isolators within the ATLAS Control Unit (ACU) can prevent an enable signal from being sent to the TACS Control Units (TCUs).

The ATLAS system is installed on Textron Model 525, 525A, and 525B airplanes under STC No. SA03842NY and lessens the increased wing loads associated with the installation of winglets. The ATLAS is designed to detect flight conditions and modify airflow at the wing tip accordingly. The ATLAS will draw power constantly to operate the logic circuit and provide power to the actuators to maintain TACS position.

The TCUs include the linear electric actuators and motor controllers that move the TACS. Since the enable signals are not monitored after the opto-isolators, the ACU cannot detect whether the generated signal is reaching the TCUs. The TCUs rely on the enable signal to determine whether to respond to commands from the ACU. If one of the opto-isolators fails, the ACU would not be able to detect that the TCUs were not enabled and the TCUs would not respond to commands from the ACU. Thus, the system would be operating in a mode of un-annunciated loss of load alleviation. The flight crew would be unaware of a malfunction of the load alleviation function of ATLAS and could fly the airplane into conditions that exceed the limit load. In addition, fatigue concerns could result in cracking of the airplane's primary structure. If not addressed, this condition could result in loss of continued safe flight and landing of the airplane.

FAA's Determination

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.

Related Service Information Under 1 CFR Part 51

The FAA reviewed Tamarack Aerospace Service Bulletin SBATLAS–57–06, Issue A, dated April 19, 2023. This service information specifies procedures for installing placards on the left-hand inboard edge of the TACS to enhance visibility of TACS movement during night operations.

The FAA also reviewed the following AFM supplements, which contain, among other items, instructions for pre-flight checks of the ATLAS system before taxi. These documents are distinct because they apply to different airplane models.

• Tamarack Aerospace Cessna Citation Model 525, 525–0001 thru –0359, AFM Supplement TAG–1101–0099 CA/DD/M023, Tamarack Active Technology Load Alleviation System (Atlas) Winglets, Issue D, dated September 20, 2023.
• Tamarack Aerospace Cessna Citation Model 525, 525–0360 through –0599, AFM Supplement TAG–1101–1099 CA/DD/M037, Tamarack Active Technology Load Alleviation System (Atlas) Winglets, Issue D, dated September 20, 2023.
• Tamarack Aerospace Cessna Citation Model 525, 525–0600 through –0684 and –0686 through –0701, AFM Supplement TAG–1101–1099 CA/DD/M038, Tamarack Active Technology Load Alleviation System (Atlas) Winglets, Issue D, dated September 20, 2023.
• Tamarack Aerospace Cessna Citation Model 525, 525–0685 and –0800 and on, AFM Supplement TAG–1101–M099 CA/DD/M088, Tamarack Active Technology Load Alleviation System (Atlas) Winglets, Issue D, September 20, 2023.
• Tamarack Aerospace Cessna Citation Model 525A, 525A–0001 thru –0299, AFM Supplement TAG–1102–0099 CAS/AFM0003, Tamarack Active Technology Load Alleviation System (Atlas) Winglets, Issue C, September 20, 2023.
• Tamarack Aerospace Cessna Citation Model 525A, 525A–0300 and on, AFM Supplement TAG–1102–P099 CAS/AFM0004, Tamarack Active Technology Load Alleviation System (Atlas) Winglets, Issue C, September 20, 2023.
• Tamarack Aerospace Cessna CitationJet Model 525B, 525B–0001 thru 525B–0056 and 525B–0058 thru 525B–0450, AFM Supplement TAG–1103–0099 CAS/AFM0001, Tamarack Active Technology Load Alleviation System (Atlas) Winglets, Issue C, September 20, 2023.
• Tamarack Aerospace Cessna CitationJet Model 525B, 525B–0057 and 525B–0451 and on, AFM Supplement TAG–1103–P099 CAS/AFM0002, Tamarack Active Technology Load Alleviation System (Atlas) Winglets, Issue D, September 20, 2023.

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 .

Proposed AD Requirements in This NPRM

This proposed AD would require installing placards on the left-hand inboard edge of the TACS and revising the existing AFM for your airplane. Revising the AFM for your airplane by updating the Normal Procedures section may be performed by the owner/operator (pilot) holding at least a private pilot certificate may revise the AFM for your airplane and must enter compliance with the applicable paragraph of this proposed AD into the airplane maintenance records in accordance with 14 CFR 43.9(a) and 91.417(a)(2)(v). The pilot may perform this action because it only involves revising the flight manual. This action could be performed equally well by a pilot or mechanic. This is an exception to the FAA's standard maintenance regulations.

Costs of Compliance

The FAA estimates that this AD, if adopted as proposed, would affect 148 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
Install placards	0.50 work-hour × $85.00 per hour = $42.50	$20	$62.50	$9,250
Revise AFM	1 work-hour × $85 per hour = $85	0	85	12,580

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:

Textron Aviation Inc. (Type Certificate Previously Held by Cessna Aircraft Company): Docket No. FAA–2024–0470; Project Identifier AD–2023–00694–A.

(a) Comments Due Date

The FAA must receive comments on this airworthiness directive (AD) by May 6, 2024.

(b) Affected ADs

None.

(c) Applicability

This AD applies to Textron Aviation Inc. (type certificate previously held by Cessna Aircraft Company) Model 525, 525A, and 525B airplanes, all serial numbers (S/Ns), certificated in any category, with Tamarack active technology load alleviation system (ATLAS) winglets installed in accordance with Supplemental Type Certificate No. SA03842NY.

(d) Subject

Joint Aircraft System Component (JASC) Code 2770, Gust Lock/Damper System.

(e) Unsafe Condition

This AD was prompted by a report of an un-annunciated failure of the ATLAS system. The FAA is issuing this AD to address un-annunciated loss of load alleviation which, if not addressed, could lead to the flight crew flying the airplane into conditions that exceed the limit load, as well as fatigue cracking in the airplane's primary structure. This could result in loss of continued safe flight and landing of the airplane.

(f) Compliance

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

(g) Required Actions

Within 60 hours time-in-service or 6 months after the effective date of this AD, whichever occurs first, do the actions required by paragraphs (g)(1) and (2) of this AD.

(1) Install placards on the left-hand Tamarack active camber surface (TACS) in accordance with steps 1 through 3 of the Accomplishment Instructions in Tamarack Aerospace Service Bulletin SBATLAS–57–06, Issue A, dated April 19, 2023.

(2) Revise the Normal Procedures section of the existing airplane flight manual (AFM) for your airplane by adding the information in Figure 1 to paragraph (g)(2) of this AD under “Before Taxi” or by incorporating the AFM supplement applicable to your airplane identified in Figure 2 to paragraph (g)(2) of this AD. Using a different document with information identical to this information under “Before Taxi” in the AFM for your airplane is acceptable for compliance with the requirements of this paragraph. The owner/operator (pilot) holding at least a private pilot certificate may revise the existing AFM for your airplane and must enter compliance with the applicable paragraph of this AD into the airplane maintenance records in accordance with 14 CFR 43.9(a) and 91.417(a)(2)(v). The record must be maintained as required by 14 CFR 91.417, 121.380, or 135.439.

Figure 1 to Paragraph (g)(2)—ATLAS Check Procedure

Figure 2 to Paragraph (g)(2)—Tamarack ATLAS AFM Supplements

(h) Alternative Methods of Compliance (AMOCs)

(1) The Manager, West Certification 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 West Certification Branch, send it to the attention of the person identified in paragraph (i) of this AD and email it 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.

(i) Related Information

For more information about this AD, contact Anthony Caldejon, Aviation Safety Engineer, FAA, 3960 Paramount Boulevard, Lakewood, CA 90712; phone: [phone]; email: [e-mail].

(j) Material Incorporated by Reference

(1) The Director of the Federal Register approved the incorporation by reference 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) Tamarack Aerospace Cessna Citation Model 525, 525–0001 thru –0359, Airplane Flight Manual (AFM) Supplement TAG–1101–0099 CA/DD/M023, Tamarack Active Technology Load Alleviation System (Atlas) Winglets, Issue D, dated September 20, 2023.

(ii) Tamarack Aerospace Cessna Citation Model 525, 525–0360 thru –0599, AFM Supplement TAG–1101–1099 CA/DD/M037, Tamarack Active Technology Load Alleviation System (Atlas) Winglets, Issue D, dated September 20, 2023.

(iii) Tamarack Aerospace Cessna Citation Model 525, 525–0600 through –0684 and –0686 through –0701, AFM Supplement TAG–1101–1099 CA/DD/M038, Tamarack Active Technology Load Alleviation System (Atlas) Winglets, Issue D, dated September 20, 2023.

(iv) Tamarack Aerospace Cessna Citation Model 525, 525–0685 and –0800 and on, AFM Supplement TAG–1101–M099 CA/DD/M088, Tamarack Active Technology Load Alleviation System (Atlas) Winglets, Issue D, September 20, 2023.

(v) Tamarack Aerospace Cessna Citation Model 525A, 525A–0001 thru –0299, AFM Supplement TAG–1102–0099 CAS/AFM0003, Tamarack Active Technology Load Alleviation System (Atlas) Winglets, Issue C, September 20, 2023.

(vi) Tamarack Aerospace Cessna Citation Model 525A, 525A–0300 and on, AFM Supplement TAG–1102–P099 CAS/AFM0004, Tamarack Active Technology Load Alleviation System (Atlas) Winglets, Issue C, September 20, 2023.

(vii) Tamarack Aerospace Cessna CitationJet Model 525B, 525B–0001 thru 525B–0056 and 525B–0058 thru 525B–0450, AFM Supplement TAG–1103–0099 CAS/AFM0001, Tamarack Active Technology Load Alleviation System (Atlas) Winglets, Issue C, September 20, 2023.

(viii) Tamarack Aerospace Cessna CitationJet Model 525B, 525B–0057 and 525B–0451 and on, AFM Supplement TAG–1103–P099 CAS/AFM0002, Tamarack Active Technology Load Alleviation System (Atlas) Winglets, Issue D, September 20, 2023.

(ix) Tamarack Aerospace Service Bulletin SBATLAS–57–06, Issue A, dated April 19, 2023.

(3) For service information identified in this AD, contact Tamarack Aerospace Group, Inc., 2021 Industrial Drive, Sandpoint, ID 83864; phone: [phone]; website: tamarackaero.com/customer-support.

(4) You may view this service information at 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.

(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 March 11, 2024.

Victor Wicklund,

Deputy Director, Compliance & Airworthiness Division, Aircraft Certification Service.