Comment from DANIEL V GASCON

Daniel Vincent Gascon
School of Engineering, University of Alabama at Birmingham
ASEM 616: Policy Issues in Prevention through Design
Professor Pam Walaski
April 19th , 2024

 
Safety Analysis
I am writing to comment on the Proposed Rule on Airworthiness Directives for Textron Aviation regarding Active Technology Load Alleviation System (ATLAS) annunciated failures and the proposal to install placards on the Tamarack Active Camber Surface (TACS) for aircraft models 525 and 525A-B. As a previous aviation safety professional and current systems safety engineer, I understand the risk of exceeding the limit load, which can affect the aircraft's landing and overall structural integrity. The proposal to install placards and revise the Airplane Flight Manual (AFM) is an acceptable preventative measure to ensure the ATLAS system works appropriately. However, more can be implemented to ensure a safe flight. The examples below support the implementation of this proposal.
According to a National Transportation and Safety Board (NTSB) investigation, “a Cessna Citation CJ2 on an IFR flight from Indiana to Chicago crashed after losing control in flight. The NTSB investigation determined, in 2021, that the ATLAS system had malfunctioned, inducing a roll from which the aircraft did not recover” (Burton, 2024). During this period, all ATLAS-equipped aircraft were grounded, and six other reports of uncommanded roll events were submitted to the Aviation Safety Reporting System (ASRS). It was decided after Tamarack Aerospace Group pushed back on the investigation that the ATLAS was not the probable cause, and according to the NTSB, the final determination was “Not Determined.” This determination does not address the original conclusion, and it was finalized that the evidence provided did not prove that the ATLAS failed.
Federal Register 2012-17864; Special Conditions: Tamarack Aerospace Group, Cirrus Model SR22; Active Technology Load Alleviation System (ATLAS), effective July 13, 2013, discusses special conditions for Cirrus SR22 aircraft to install winglets and ATLAS. “The installation of winglets, as proposed by Tamarack, increases aerodynamic efficiency. However, the winglets also increase wing static loads and the wing fatigue stress ratio, which may exceed the certificated wing design limits under limited gust and maneuver load factors. The addition of ATLAS mitigates the adverse effects of the winglets by effectively aerodynamically turning off the winglet at elevated gust and maneuver load factors” (FR 2012-17864, 2013). If the ATLAS system malfunctions during flight or landing, the winglets put the wings at risk of structural failure. The docket discusses the Factors of Safety and conditions that the ATLAS shall be in to have a flight, including that the load alleviation system must be in compliance and have a warning, which is distinguishable to the pilot under expected flight conditions without requiring the pilot’s attention and must be provided for any failure in the load alleviation system or in any other automatic system that could result in an unsafe condition if the pilot was not aware of the failure.
This proposal addresses the failure of the annunciation of the ATLAS, and there is clear evidence of inconsistencies and significant risk to the pilot and personnel on the aircraft if it were to fail. The ATLAS and TACS are safety-critical functions to the aircraft and require in-depth system hazard analysis to determine the probability of failure in different flight conditions. Installing a placard may help pilots, but training and inspection checks will ensure compliance and safety of the aircraft. The urgency of this essential equipment should be established for pilots using this aircraft, and I would advise the manufacturer to send an advisory and proper maintenance instructions for these components.

References
Burton, N. (2024, February 29). NTSB reverses findings that pinned fatal accident on Tamarack
Winglets. AOPA. https://www.aopa.org/news-and-media/all-news/2024/february/29/ntsb-reverses-findings-that-pinned-fatal-accident-on-tamarack-winglets
Airworthiness Directives; Textron Aviation Inc. (Type Certificate Previously Held by Cessna
Aircraft Company Airplanes), 89 F.R 20354 (proposed March 22, 2024) (AD-2023-00694-A). chrome-extension://efaidnbmnnnibpcajpcglclefindmkaj/https://www.govinfo.gov/content/pkg/FR-2024-03-22/pdf/2024-05477.pdf
Special Conditions: Tamarack Aerospace Group, Cirrus Model SR22; Active Technology Load
Alleviation System (ATLAS), 77 F.R. 42949 (effective date July 13, 2013) (Special Conditions No. 23-258-SC). https://www.federalregister.gov/documents/2012/07/23/2012-17864/special-conditions-tamarack-aerospace-group-cirrus-model-sr22-active-technology-load-alleviation

Comment Date:2024-04-22T04:00:00Z

Comment On Document ID:FAA-2024-0470-0003

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