The US National Transportation Safety Board (NTSB) has cited a faulty lithium-ion battery bank as the "probable cause" behind the fire that destroyed the 24.9-metre catamaran, Flagship. The incident occurred last year (April 2024) at Merrill-Stevens Yachts' repair yard in Miami, Florida, with the VisionF build declared "a total loss" valued at $5 million.
The agency found that Flagship's inoperable battery management systems led to a practice of manually charging the batteries with a portable charger, which compromised their safe monitoring.
"Upon arrival, units found a large vessel fully engulfed in flames," read a statement from the City of Miami Department of Fire Rescue at the time. "They encountered very low visibility because of the billowing smoke and due to the complexity of the incident, a second alarm was requested."
The statement continued: "Over 34 units and 100 firefighters, including the Hazmat Team and Fireboat, worked together to extinguish the blaze in just over an hour. As a precautionary measure, all nearby vessels were safely relocated to prevent any damage."
The National State Warning Point was also notified to conduct an assessment into any environmental consequences, including potential spill-off.
Flagship was built within the Turkish yard's VisionF 82 series. As a catamaran, she was characterised by her beamy build (at 9.9 metres wide), alongside an owner's cabin with a "spa-like" en suite and a flybridge complete with sunpads and 360-degree visibility.