Tamarack winglet restrictions eased

“The AMOC is an intermediate step meant to provide a way for the affected CitationJets to fly sooner than waiting for the final resolution of the AD, which will come later,” Tamarack noted in a July 10 press release, adding that aircraft that comply with related service bulletins may resume flight without the restrictions imposed by the airworthiness directive published May 24 that grounded all Citations with Tamarack active winglet systems installed.

The FAA AD published May 24 followed a similar action by European regulators, and grounded 91 aircraft worldwide. Tamarack responded with formal comments on May 29 from the firm’s chief engineer, who noted that service bulletins issued by Tamarack and Cranfield Aerospace Solutions that predated both ADs provided “proactive product enhancements” that made the active load alleviation system (ATLAS) more reliable, and “also help neutralize the impact of system failures.”

Tamarack noted in the July 10 press release that 89 of the 91 ATLAS-equipped aircraft around the world are now in compliance with applicable service bulletins.

Improvements called for in service bulletins dating to 2018 include hardening of the system’s control unit to prevent short-circuits, and installation of “centering strips,” which are designed to hold the active winglet in the faired position in case of failure. The active winglets are computer-controlled surfaces on the outboard ends of the wing designed to automatically counter excessive loads created by the winglets in certain conditions. The FAA cited potential loss of aircraft control in the May AD as justification for immediate grounding. Tamarack objected to the FAA’s characterization of the risk.

Tamarack filed for Chapter 11 bankruptcy protection in June, vowing to work with regulators to resolve safety concerns and continue operations and customer support. Tamarack said the bankruptcy would be a temporary step to “ensure the long-term viability of the company.”

“This AMOC will allow our customers to resume normal flight operations as quickly as possible. I offer my sincere thanks to our loyal and supportive customers during this challenging time. They have been our staunchest advocates despite the inconvenience and hardship of having the use of their aircraft restricted,” Tamarack founder and CEO Nicholas Guida said in the July 10 press release. “I am pleased to announce that we have booked three Active Winglet deposits during the FAA grounding, and we are scheduling new installations now. Tamarack is focused on the future and providing the most innovative and advanced winglet solutions in aviation.”