At a little before 7:30, on the evening of April 27, 2014, Helen Greer looks out through the screened-in back porch toward the river. “Don,” she says, “don’t you think you should come look at this?”
Her husband of forty-one years appears at her side and looks to the south. From this spot at the northern edge of the small River Plantation subdivision, near Mayflower, Arkansas, he can see the homes of his neighbors and beyond, the cone of Pinnacle Mountain rising above the pine and hickory woods along the banks of the Arkansas River. It is the way the clouds are moving that is upsetting Helen. She asks Don, “Don’t you think we should go to the safe room?” Don squints at the sky above the treetops and the low ridgeline and sees no reason for panic. “Just a bunch of clouds moving around out there,” he says. The wind moans and the trees in the yard toss. It happens a lot this time of year.
Don is a builder by trade and has overseen the construction of many of the houses in the neighborhood—a mix of modest, single-story wood-frame and brick homes, along with a few McMansions closer to the river. Their son, Donnie, lives next door, and their grandson plays in a yard just feet from their own. Helen spends hours tending her rose garden and when the bushes are in bloom it’s the pride of their quiet block. During the day, purple martins fly in and out of the birdhouse in the backyard. At night, Don and Helen often pass the time on the back porch, where her two schnauzers snore in her lap. They watch fireflies flickering in the woods and listen to the coyotes hollering up and down the train tracks. Sitting out there, at eighty years of age, Don feels like he’s done pretty well in this life.
On this night, the lightning keeps getting closer, louder. The schnauzers have run off some place, hiding. Don scans the darkening sky in the southwest—like night is coming on. But all he can see out there is rain falling in deep-gray curtains over the river. This isn’t the first time the weather has kicked up like this. Almost three years ago to the day, Don had watched from the lee of his house as a storm swept over the valley, and a barrel-shaped tornado howled up Palarm Creek. Though it came within a few thousand feet of their home that day, it never got so bad that they needed to use the tornado shelter in the corner of the house—what Helen calls the safe room.
Don finds the dogs beneath the couch. They won’t come out. Gusts roar out of the pines in the north, rushing past the house toward the river. Helen heads for the shelter. Don still isn’t worried, so he leaves the dogs and follows his wife as much for her peace of mind as anything else. He enters the bedroom and steps into the eight-by-eight-foot shelter that also serves as their walk-in closet and gun safe. He shuts the door behind him, and though the events that follow remain fragmented in his mind, he is certain he has locked the three deadbolts.
He never sees the tornado, but within seconds he hears it, like sand hissing against steel. The door begins to groan and flex back and forth on the hinges and deadbolts. The staccato of heavy objects striking the shelter is deafening, like being fired upon by a machine gun loaded with bricks. Don throws himself against the door and pushes with everything he has. Helen is a small woman, but she too finds her strength, and she stands between her husband’s arms to help him brace against the wind outside.
Six hundred fifty miles to the west, a man named Larry Tanner has spent nearly two decades studying the kind of wind that is screaming through Mayflower—and how to defend against it. He runs the laboratory at the National Wind Institute, a Texas Tech research center that serves as a hub for the study of everything from wind energy to wind-hazard mitigation. Housed in a hangar at what used to be Reese Air Force Base, on the outskirts of Lubbock, Texas, it contains a massive, two-story vortex simulator; a wind tunnel capable of generating a sustained gale of up to 110 miles per hour; and, in a far corner, the Debris Impact Facility.
Tanner has a ruddy face, a thick, west-Texas drawl, and a shock of cotton-colored hair. He is an architectural engineer, a student of catastrophic tornadic events, and the world’s foremost expert in tornado shelters. Three years after the Mayflower storm, Tanner stands behind a protective wall of clear Lexan paneling, reading from a clipboard in the officious monotone of a man about dull work. Some of what he says is a recitation of FEMA codes, but the gist is, he’s about to propel a fifteen-pound projectile a hundred miles per hour at an aboveground steel-panel tornado shelter to simulate the debris impacts generated by a tornado packing 250-mile-per-hour winds.
Don finds the dogs beneath the couch. They won’t come out.
With the record satisfactorily established for the video camera, Tanner steps from behind the screen to another, safer enclosure even farther back, because the debris cannon is online. Known as the potato gun on steroids, the cannon draws on both atmospheric science and applied engineering. Its howitzer-like barrel is twenty feet long, four inches wide, and is attached to a thirty-gallon compressed-air tank. Where the two meet, a butterfly valve is capable of draining the entire thirty gallons within several thousandths of a second. No gunpowder. No explosives. Just the force of air.
The steel-panel shelter—the victim of today’s testing—sits eighteen feet from the muzzle. As ammunition, Tanner will use the most common missile found swirling within high-end twisters: a two-by-four. His assistant and cannoneer, Tanner Pletcher, a Texas Tech senior studying civil engineering, shoves the plank down the barrel and rams it home with a makeshift plunger. He steps behind the control panel and begins punching keys on a laptop.
“Arming,” he shouts. A pneumatic rushing issues from the tank as it pressurizes. The cannon’s green laser sight paints the middle of the shelter’s 250-pound steel door, right at one of its slide bolts. A klaxon sounds three times, resounding through the hangar. “Clear,” Pletcher yells. “Three . . . two . . . one . . .”