Jeff Henry and his longtime friend and business partner, John Schooley, had coupled an ambitious goal with an impossible timeline: Build the world’s tallest waterslide and get it featured on a Travel Channel show about water parks, all in a few short months.

What the two men did not have, prosecutors say, were credentials in mathematics, physics or engineering — essentials to safely bring their dream to fruition.

It ended tragically in August 2016. Ten-year-old Caleb Schwab was decapitated on the ride named Verrückt — the German word for “insane.” The ensuing swarm of investigators said they found signs of rushed construction and a trail of negligence leading back to Henry and Schooley, prosecutors say.

Now, the two men — magnates of the American water park industry — face second-degree murder charges. The 168-foot-7-inch tall ride — taller than Niagara Falls — has been closed, and the Guinness Book of World Records page that featured Verrückt as the world’s tallest waterslide now gives viewers an error message.

Henry was arrested March 26. Schooley, who was out of the country when the grand jury indictment was unsealed, was arrested by U.S. Marshals when he landed at Dallas/Fort Worth airport Monday night, according to Dallas NBC-affiliate KXAS.

Henry, who owned the Schlitterbahn water park and several others with his siblings, was called a visionary before he opened the world’s tallest waterslide.

A hybrid roller-coaster and waterslide ride, Verrückt was his 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.” Schooley helped with the design — and later the testing.

On Verrückt, groups of riders first zoomed down a nearly vertical, 168-foot main descent. Then they ascended 50 feet 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.

The indictment says 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.

And month after month, 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, 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 former director of operations, Tyler Austin Miles, of intercepting incident reports from lifeguards and destroying witness statements — then coaching the guards to write statements, which omitted crucial damaging details about Verrückt. He has been charged with involuntary manslaughter and several counts of aggravated endangerment and aggravated battery.

Read the full story at The Washington Post.

Ride designer Jeff Henry looks over his Verrückt creation in July 2014. The ride, at Schlitterbahn Waterpark in Kansas City, Kan., was billed as the world’s tallest waterslide. (Charlie Riedel/AP)

Verrückt waterslide designers, John Schooley, left, and Texas-based Schlitterbahn Waterparks and Resorts co-owner Jeffrey Henry, speak in 2014 about the challenges of opening the 17-story tall attraction before its operation in Kansas City, Kan. (Monty Davis/Kansas City Star/AP)

Verrückt waterslide designers, John Schooley, left, and Texas-based Schlitterbahn Waterparks and Resorts co-owner Jeffrey Henry, speak in 2014 about the challenges of opening the 17-story tall attraction before its operation in Kansas City, Kan. (Monty Davis/Kansas City Star/AP)

Ride designer Jeff Henry looks over his Verrückt creation in July 2014. The ride, at Schlitterbahn Waterpark in Kansas City, Kan., was billed as the world’s tallest waterslide. (Charlie Riedel/AP)