NTSB Says Failure to Heed Weather Warning Led to Fatal Sinking of Duck Boat

The operator of a Branson, Missouri duck boat failed to heed a severe thunderstorm warning before the fatal sinking of the Stretch Duck 7 during severe weather in July 2018, the National Transportation Safety Board said Tuesday. 

Known hazards such as fixed canopies and the Coast Guard’s failure to require sufficient reserve buoyancy in “duck boats” contributed to the accident.

The World War II-era amphibious DUKW “duck boat” sank on July 19, 2018 during a strong thunderstorm with winds up to 73 mph on Table Rock Lake near Branson, Missouri, killing one crew member and 16 passengers.

Update: NTSB Full Report – Sinking of Amphibious Passenger Vessel Stretch Duck 7 

The Stretch Duck 7 was operated by Ripley Entertainment Inc., aka Ride The Ducks of Branson. 

The findings of the NTSB’s investigation and a synopsis of its final report were released Tuesday during a virtual public board meeting. 

“Ride the Ducks of Branson continued to operate waterborne tours after a severe thunderstorm warning had been issued. This exposed the vessel to a derecho, which resulted in waves flooding through a non-weathertight air intake hatch on the bow, which caused the vessel to sink,” the NTSB determined. 

During the investigation, NTSB investigators discovered that the National Weather Service had issued a severe thunderstorm watch for the area several hours prior to the sinking. The forecast was then updated to a severe thunderstorm warning one minute before Stretch Duck 7 departed the shoreside boarding area, located about 6 miles from the lake. Investigators noted three other company vessels also entered the lake after the severe thunderstorm warning was issued.

The captain of the Stretch Duck 7 survived the accident and eventually indicted on multiple charges including misconduct, negligence and inattention to duty. Two others from Ripley Entertainment were also later charged.

“Had Ride The Ducks employees taken more appropriate actions and made better decisions, it is likely the duck boat would not have sunk, because they would not have continued operations based on the weather forecast and prevailing conditions,” said NTSB Chairman Robert Sumwalt.

The NTSB also cited U.S. Coast Guard’s failure to require sufficient reserve buoyancy in amphibious vessels as contributing to the accident. The NTSB investigators found that the duck boat was originally constructed with a low freeboard, an open hull, and no subdivision or flotation, which resulted in a design without adequate reserve buoyancy. 

The NTSB noted previous inaction to address emergency egress on amphibious passenger vessels with fixed canopies which impeded passenger escape from the Stretch Duck 7. Both reserve buoyancy and improved emergency egress, including the fixed canopies, were the subject of a previous NTSB Marine Safety Recommendation issued in November 2019. 

The NTSB said that the fixed canopy of the Stretch Duck 7 directly contributed to the severity of the accident. “When the vessel sank, the closed starboard-side curtain aboard the vessel impeded the passengers’ escape and likely resulted in additional fatalities,” the NTSB said.

The NTSB has issued six safety recommendations with three recommendations issued to the Stretch Duck 7’s operator and three recommendations to the U.S. Coast Guard, addressing safety issues including company oversight, engine compartment ventilation closures, reserve buoyancy, survivability, weather training for mariners, and Coast Guard guidance.

Since the 1999 fatal accident involving the Miss Majestic DUKW, the NSTB has now issued a total of 28 safety recommendations related to modified WWII-era DUKW passenger vessels. Among the 22 previously issued, only nine had been implemented fully by the Coast Guard as of November 2019.

The NTSB’s final report, which includes the findings, probable cause, and all safety recommendations, is available at https://go.usa.gov/xvEzG.

A final report for the investigation is expected to be published in the next few weeks.