Investigation into fatal Missouri duck boat sinking could take a year to complete, officials say

The National Transportation Board said it could take a year for its federal investigation to provide concrete answers on what caused a tourist-packed duck boat to sink in a Missouri lake.

Two crew members and 29 passengers were aboard the “Ride the Ducks” sightseeing vessel when in capsized on Table Rock Lake in Branson Thursday evening. Seventeen people — nine of them from the same family — were killed when the boat plunged 80 feet to the bottom of the lake. Those who died range in age from 1 year to 70 years old.

While a severe thunderstorm tore through the Branson area around the same time the duck boat sank, it’s still unclear as to what exactly caused the re-purposed World War II craft to take on water.

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“We will do an analysis of the fact and approximately one year later — one year from now — we should have a probably cause and a report for the general public,” Earl Weener wtih the NTSB told CNN. “We can expect to have a preliminary factual report in a couple of weeks to a month.”

Branson and the surrounding area was placed under a severe thunderstorm watch shortly after 6:30 p.m. local time, a little more than 40 minutes before the first 911 calls started rolling in. First responders rushed to the lake, launching a hunt for survivors and victims that wore into the night.

Earlier in the day, officials implemented a severe thunderstorm watch, providing ample time to prepare for the impending weather.

Jim Pattison Jr., the head of the tour company involved in the deadly sinking at a Missouri lake said the duck boat “shouldn’t have been in the water” when it capsized Thursday night, adding the weather appeared calm when the fatal tour kicked off.

But the waters quickly became choppy and the winds picked up, at one point reaching speeds of 65 mph.

The National Transportation Safety Board previously sounded that alarm on the amphibious crafts in 1999, when the Miss Majestic duck boat sunk to the bottom of Lake Hamilton in Arkansas, killing 13 of the 21 passengers on board.

“Contributing to the high loss of life was a continuous canopy roof that entrapped passengers within the sinking vehicle,” the NTSB investigation concluded at the time. It continued on to express concerns that the boats were prone to flooding and “the vulnerability of sinking,” with officials recommending to outfit the crafts with watertight bulkheads and install flotation materials.

The six-wheeled vehicles were designed to land WWII soldiers from sea to soil, though dozens of them remain in operation across the country to shuttle tourists to popular locations by both land and water.