Schlitterbahn's Verruckt water slide. Credit:AP The Schlitterbahn company and Tyler Austin Miles, the former director of operations, have already been charged with involuntary manslaughter and several counts of aggravated battery, aggravated endangering a child and interference with law enforcement in the Verrückt investigation, according to an indictment in Wyandotte County, Kansas, that was unsealed last week. A hybrid roller-coaster and waterslide ride, Verrückt was Henry's brainchild. Investigators say he decided to build it in a "spur-of-the-moment bid to impress producers of Travel Channel's Xtreme Waterparks series." Tyler Miles, an executive with the Kansas water park where a 10-year-old boy died on a giant waterslide has been charged with involuntary manslaughter. Credit:AP He and a longtime friend and business partner, John Schooley, were the chief designers, the indictment says, even though neither had any credentials in mathematics, physics or engineering.

On Verrückt, groups of riders first zoomed down a nearly vertical, 168-foot (51 metre) main descent. Then they ascended 50 feet (15 metres) above the ground, propelled by inertia and "a series of high-pressure water blasters," according to the indictment. But in some instances, instead of sliding straight down, the rafts went airborne - a major design flaw that investigators say the company had known about, tried unsuccessfully to fix, and eventually ignored. Most of the slide is covered with a net suspended by metal hoops, an industry-defying addition that investigators say hints at Verrückt's danger. Caleb Thomas Schwab, who died while riding the Verruckt, a water slide. Credit:AP The indictment says that the ride creators' calculations were off and that they knew it. Some of the rafts would go airborne before the second drop, causing riders to strike the net or the suspended metal hoops that held it. The injuries piled up.

In the two years that Verrückt was in operation, 13 people were injured, many after the rafts left the slide, according to court documents. A month after the ride opened, a 14-year-old received a concussion, the court papers say. The next summer, another teen was concussed and a 20-year-old woman suffered a slipped spinal disk. The woman, Brittany Hawkins, was a lifeguard who knew the park's operator and told him she was injured after her raft went airborne. The indictment accuses the operator, Miles, of intercepting incident reports from lifeguards and destroying witness statements - then coaching the guards to write statements that omitted crucial damaging details about Verrückt. The "Verruckt" raft ride at the Schlitterbahn WaterPark in Kansas City, Kansas. Credit:AP/Erin Oberhausen Caleb climbed into the front seat of one of the ride's rafts on August 7, 2016, which the park had dubbed Elected Official Day.

By the end of the minute-long ride, Caleb, the son of Kansas state Representative Scott Schwab, was dead after being decapitated. Two women riding with him suffered cuts and fractures. Their raft had collided with a metal pole that held the net. Investigators uncovered a string of negligence that they say led back to Henry. Henry and Schooley had rushed the design process in part because they wanted the ride to be on TV, the court documents said. A simple waterslide can require months of calculation, computer modeling and prototyping by trained engineers before builders break ground. But investigators say that engineers were never directly involved in Verrückt's conception or design and that Henry and his team completed a prototype within 36 days. Because of the rush, the indictment says, they "skipped fundamental steps in the design process. In place of mathematical and physics calculations, they rushed forward relying almost entirely on crude trial-and-error methods."

In some instances, they watched dummies speed down the hill and then fly off the ride, the court documents say. Still, the ride sped toward its opening. Emails from Henry spoke of the breakneck pace to get the ride up and running. "I must communicate reality to all. Time, is of the essence. No time to die. J." he said in one email. In another: "This is a designed product for TV, absolutely cannot be anything else. Speed is 100 per cent required. A floor a day. Tough schedule." Henry and his team also communicated to each other about the dangers. "Verrückt could hurt me, it could kill me, it is a seriously dangerous piece of equipment today because there are things that we don't know about it," Henry wrote in one message. "Every day we learn more . . . I've seen what this one had done to the crash dummies and to the boats we sent down it. Ever since the prototype. And we had boats flying in the prototype too. It's complex, it's fast, it's mean. If we mess up, it could be the end. I could die going down this ride."

Because of the ride's "extreme nature," the indictment says, Henry and Schooley considered a rider-age restriction, first 16 years old, then 14. But on the eve of the grand opening, they decided to remove the restriction. The signs with the age restriction had already been printed, the indictment says, so they covered them with stickers. Schlitterbahn spokeswoman Winter Prosapio took issue with several claims in the indictment and denied that the company and Miles withheld or altered evidence. Caleb's death, she said in a statement emailed to The Washington Post, was the result of an accident and not of a crime: "We were shocked by the allegations being made by the Attorney General about Tyler and our KC park. The allegation that we operated, and failed to maintain, a ride that could foreseeably cause such a tragic accident is beyond the pale of speculation. Many of us, and our children and grandchildren, have ridden the ride with complete confidence as to its safety. Our operational mantra has been and will forever be Safety First.

"The accusation that we withheld information or altered evidence is completely false. We have operated with integrity from day one at the water park - as we do throughout our water parks and resorts. We put our guests and employees safety first; and safety and maintenance are at the top of our list of priorities." In a statement, Miles' attorney, Tricia Bath, said that her client did not knowingly obstruct the police investigation and that Miles and his own family members had ridden the slide several times. Still, Caleb's family has received about $US20 million in settlement payments from the water park and other companies involved in his death, the Kansas City Star reported last year. "When your bill dies, or your amendment fails . . . let it go," Scott Schwab said on the Statehouse floor in January 2017, referencing his son's death, according to the Kansas City Star. "Life isn't worth wasting too much emotional energy on such things. I just want you to know, it could get worse." Washington Post