The 17 people who were killed last week after a duck boat sank in Missouri were riding in an amphibious vehicle designed by a self-taught businessman who had no formal training in engineering or mechanics, according to court records.

Robert F. McDowell owned and ran Ride the Ducks in Branson, Mo., for nearly three decades. In the 1980s, he came up with the idea of redesigning the company’s amphibious passenger vehicles by stretching them by 15 inches, and by the mid-1990s, Ride the Ducks was manufacturing what’s called “stretch” duck boats, according to court filings from a pending lawsuit filed against the company over a fatal crash in Seattle. Fast-forward to 2018, one of those boats built based on McDowell’s design, carrying 29 passengers and two crew members, sank to the bottom of Table Rock Lake amid torrential storms.

It remains unknown whether McDowell’s design was a factor in the boat’s sinking. A spokesman for the National Transportation Safety Board, which is investigating the accident, confirmed that the vehicle that sank was, in fact, a “stretch” boat and said its design and how it was built are part of the ongoing probe.

Ride the Ducks’s boats, which the company said were replicas of World War II Army vehicles used in beach landings and were updated with modern safety equipment, and McDowell’s lack of formal credentials have been a concern among some lawyers in the last few years. Public officials also recently called into question the safety and structural integrity of the boats after the deaths of the 17 tourists in Branson last week.

McDowell did not have a degree or certification in engineering or mechanics. He spent 2 1/2 years as a pre-medicine student at Illinois Wesleyan University before moving to Branson in the 1970s to take over the management of Ozark Scenic Tours, which his father had bought and would later become Ride the Ducks, court records say. He educated himself on how to run the boat operation by talking to its previous owners, a high school football coach and a doctor, he said in a deposition as part of the Seattle lawsuit. He learned about mechanics and vehicle maintenance by spending a lot of time at auto shops.

In stretching the length of the duck boats, McDowell said he and his staff did research on businesses that use similar passenger vehicles. He visited Penske Trucks, U-Haul and United Parcel Service. No structural engineers were consulted, court records say.

“It was a journey and a gradual learning curve, and we continued to stay after it until we worked through the detail of it and developed it,” McDowell said in the deposition.

McDowell, who is not a defendant in the Seattle lawsuit, did not return a call from The Washington Post on Wednesday. A spokeswoman for Ripley Entertainment, Ride the Ducks’s parent company, did not answer emailed questions and, instead, referred The Post to a statement on the company’s website saying that it cannot comment because of the pending investigation.

Karen Koehler, a lawyer who represents plaintiffs injured in a 2015 crash involving a Ride the Ducks boat and a charter bus in Seattle, said she had always assumed that building the amphibious vehicles required expertise from structural engineers.

The duck boat that sank in Table Rock Lake in Branson, Mo., is raised on Monday. The boat went down a few days earlier after a thunderstorm generated near-hurricane strength winds. (Nathan Papes/Springfield News-Leader via the Associated Press)

“I don’t want to turn this man into a villain or anything like that,” she said, referring to McDowell. “He had a vision and wanted this to happen and he made it happen … I just think, gosh, it would be like me practicing without a law license.”

The crash in Seattle was caused by a faulty axle and not by the boat’s design, Koehler said. But she said stretching the vehicles was a concern.

“Any time you alter something that basic in a vehicle, you change how the vehicle works, how it vibrates, how different things are stressed,” she said.

Rain and 65 mph wind gusts pummeled the amphibious boat Thursday evening while it was on a sightseeing tour of the picturesque Ozarks lake. Gripping video footage showed the boat seesawing and lurching in unrelenting waves. The boat capsized, plunging 80 feet to the bottom. Fourteen people — fewer than half of the boat’s occupants — survived.

Killed was the boat’s driver, Branson resident Robert “Bob” Williams, 73, and tourists from four states. William Asher, 69; Rosemarie Hamann, 68; Janice Bright, 63; and William Bright, 65, were from Missouri. Steve Smith, 53; and Lance Smith, 15, were from Arkansas. Leslie Dennison, 64, was from Illinois.

The remaining nine victims were from Indiana, all members of the Coleman family: Angela, 45; Belinda, 69; Ervin 76; Glenn, 40; Horace, 70; Reece, 9; Evan, 7; Maxwell, 2; and Arya, 1. Tia Coleman, 34, and her nephew, Donovan, 13, survived.

Tia Coleman, who came to Branson with her family for their annual vacation, told reporters on Saturday that the boat company had suggested doing the “water part” of the tour before sightseeing on land because a storm was expected to roll in. The violent thunderstorm hit not long after the duck boat started out into the water.

Sitting near the front of the boat, Coleman began to worry when a giant wave crashed over the bow, she told reporters. She never heard anyone declare an emergency, she said, and the boat’s captain told passengers they didn’t need to use life jackets.

Coleman, a paralegal from Indianapolis, lost her husband and three children, ages 9, 7, and 1.

The deaths shook the community in Branson, where hundreds of residents had gathered for vigils for the victims. A spokeswoman for the Missouri attorney general said the agency is looking into whether any criminal charges are appropriate.

“The saddest thing about this is the people who went on this vehicle were doing it because they were having a great time. And that is probably a cruel irony of the situation,” U.S. Sen. Claire McCaskill (D-Mo.) said on the Senate floor on Tuesday.

McCaskill said the duck boats were a “sinking coffin” and called into question their “inherent dangers.” She said she will introduce legislation that would require “design issues” of duck boats to be addressed. For example, she questioned whether duck boats should have a canopy that would trap passengers if the vehicles sink.

“These are not open vehicles. When they’re in the water, it’s almost like an enclosed bus. It’s not a boat; it’s a vehicle,” McCaskill said.

Chad Saylor, a spokesman for the U.S. Coast Guard, said the boat that sank was last inspected on Nov. 29. The Coast Guard, which looks at lifesaving gear, navigation equipment, machinery and training of the crew, found the boat to be “fit for route and service,” Saylor said.

Amphibious vehicles have so far been involved in at least 41 deaths in the United States and Canada since 1999. Five college students were killed in 2015 after a Ride the Ducks boat crashed into a charter bus on the Aurora Bridge in Seattle. Two were killed in a duck boat accident in 2010 in Philadelphia. Four were killed after a duck boat sank in 2002 in Ottawa. Another four died on the Miss Majestic in 1999 in Arkansas after they were pinned against the underside of the duck boat’s canopy.

The year after the Seattle crash, the company agreed to pay $1 million for violating federal safety regulations, according to the Seattle Times.

According to court filings in the Seattle lawsuit, which alleges negligence, Ride the Ducks began to grow in the 1980s, with McDowell buying surplus Army Duck vehicles and parts around the country and remanufacturing the amphibious vehicles. Around the mid-1990s, McDowell began licensing and leasing Ride the Ducks vehicles in Boston and Seattle.

In 2001, McDowell sold a 50 percent share of the company to Herschend Family Entertainment. Three years later, Herschend bought the remaining shares and McDowell stayed on, first as a manager and then as a consultant, before leaving the company, court records say.

Ripley Entertainment bought the duck operation in 2017.

Mark Berman, Allyson Chiu and Emily Wax-Thibodeaux contributed to this article.

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