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Updated 11:20 AM EDT, Thu August 2, 2018
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duck boat incident witnesses
Witnesses describe 'tragic' duck boat capsize
02:09 - Source: CNN
CNN  — 

The tourist duck boat that sank two weeks ago during a thunderstorm in Missouri, killing 17 people, was prohibited from traveling on water when winds were above 35 mph, a US Coast Guard certificate of inspection says.

The Ride the Ducks Branson amphibious vessel sank July 19 as a storm and high winds lashed Table Rock Lake. The National Weather Service had warned the Branson area that winds in excess of 60 mph were approaching that evening.The highest wind gust eventually reported was 63 mph, CNN meteorologists said.

National Transportation Safety Board investigators are focusing on when the boat operators decided to take the vessel into the water and when they became aware of a severe thunderstorm warning, a source with knowledge of the investigation has said.

The water was calm when the boat entered the lake, but waves and winds picked up later, according to a timeline released by the NTSB.

The thunderstorm had traveled hundreds of miles, prompting severe-weather alerts to the northwest of the Branson area before the vessel departed the terminal, authorities have said.

The severe thunderstorm warning went out to the Branson area shortly after 6:30 p.m. –around the same time the vessel drove away from the terminal toward the lake, according to the NTSB’s timeline.

Initial gusts arrived ahead of the storm at 6:59 p.m., the CNN Weather department said. The boat sank around 7:09 p.m., authorities have said.

The NTSB timeline, citing video footage, says that before the vessel departed its terminal, a person told the captain and driver to do the water portion of the 70-minute tour before the land portion. About a minute later, the NTSB said in a news release, the captain “made a verbal reference to looking at the weather radar prior to the trip.”

Coast Guard is investigating

The certificate document filed in February 2017 by the Coast Guard also indicates the number of passengers permitted aboard the vessel and other operational guidelines.

The certificate was made public Wednesday when the Coast Guard released details about how its investigation would be structured.

The Coast Guard said it would establish a formal Marine Board of Investigation,the agency’s “highest-level investigation.”

“The Coast Guard will conduct a thorough and detailed investigation to identify all potential causal factors associated with this tragedy,” Capt. Wayne Arguin, chairman of the Marine Board of Investigation, said in a statement.

A spokeswoman for Ripley Entertainment Inc., the Branson duck tour business’s parent company, said she could not comment about the certificate or the Coast Guard’s investigation.

“Because Ripley Entertainment is an active and cooperative participant in the ongoing accident investigation by the National Transportation Safety Board, we are not authorized to provide any statement about that inquiry or the US Coast Guard’s announcement that it is joining in the analysis of the tragic event,” Ripley spokeswoman Suzanne Smagala said.

The Coast Guard had said its inquiry will determine whether the actions of any person contributed to the deadly event.

Victims’ families want ban of duck boats

Earlier this week, the administrators of the estates of two family members who died filed a wrongful death lawsuit seeking $100 million in damages from the operator of the duck boat.

When the vessel started sinking, a canopy entrapped the passengers and dragged them to the bottom of the lake, attorney Robert Mongeluzzi told reporters.

The boat sank 40 feet and then rolled to an area 80 feet deep, Stone County Sheriff Doug Rader said.

The passengers might have survived if the Branson operators had not ignored a 2002 NTSB recommendation that duck boat canopies be removed, Mongeluzzi said.

He said his clients pursued the lawsuit for two reasons.

“They want to know what happened. Why did their loved ones die?” he said. “And more importantly, they want to know that no one ever dies again inside a deathtrap duck boat. They want this lawsuit to ban duck boats.”

CNN’s Marlena Baldacci, Amanda Watts, Jason Hanna, Steve Almasy and Ralph Ellis contributed to this report.