Tornado chasers' truck shoots Imax from inside storms (photos)

Filmmaker Sean Casey has been chasing tornadoes for more than a decade. And it takes one tough ride to get in and out of the violent storms safely.

We met up with the storm chaser this week at The Tech Museum in San Jose, Calif., where his Imax film, Tornado Alley, opens today (see trailer here).

Driving directly into violent storms with an Imax camera, Casey attempts to document a high-definition view of a direct hit from an F3 tornado, giving moviegoers a large-format view of one of nature's most violent displays. (F3 tornadoes are considered severe and characterize a storm with winds of 158 mph to 206 mph.)

To accomplish this, he's built a custom, bunker-like, 14,000-pound storm-chasing truck that is armored with layers of steel and Kevlar. Tucked safely inside, he aims to plant himself and his team directly in the path of these spectacular storms.

His second-generation Tornado Intercept Vehicle, the TIV2 shown here, has been built to withstand the worst. In this slideshow, we take a tour of some of the technology used to capture this unprecedented footage--and make sure everyone makes it out unharmed.

The TIV2 looks like a tank, but with a Dodge 3500 4x4 as the chassis, the vehicle is actually incredibly agile.

To protect against projectiles hurling through tornadoes at upwards of 150 mph, TIV2 is protected by an eight-layer armor that is two inches thick. Layers of aluminum, Kevlar, more aluminum, steel, 0.5-inch-thick rubber, 0.5-inch-thick polycarbonate, more rubber, and yet more aluminum are wrapped around a squared-steel frame.

The 6.7-liter Cummins turbo diesel engine, which normally provides about 350 horsepower, is supplemented by a water and propane injection system, boosting it to an impressive 625 horsepower with a top speed of 100 mph.

The gas mileage isn't great, but it's better than you might think. At about 12 mpg, Casey says the vehicle is comparable to that of a Hummer in fuel efficiency. The TIV2 has a 92-gallon fuel tank.

F3 tornadoes produce a deafening sound. A CB radio hooked up to the sound system allows the people riding in the truck to communicate with their remote team members amidst the roar of storms.

A laptop mounted on the center console (not shown in this photo) gives the team their own GPS mapping and topography system as well as real-time weather reports and information from the roof-mounted tools to measure and record wind speeds, relative humidity, and barometric pressure.

Other communications tools, such as a public address system and sirens, are mounted on the outside and allow the team to communicate the eminent danger of an approaching storm to sometimes unaware people nearby.

The driver and passengers are protected by a 1.5-inch-thick polycarbonate windshield and windows. However, in the center of a storm, Casey says, nothing could protect them from a direct hit by a projectile such as a telephone pole or tree moving at 150 miles per hour.

With lots of exposed wires, the interior of this vehicle isn't the most organized, but some very cool buttons and features have been set up.

These six levers operate the outer hydraulic armor, which lowers to protect the vehicle from flying debris and--more importantly--a tornado's winds, which could lift the vehicle into the tornado.

The TIV2 has three driven axles with two sets of dual Hercules S-309 tires on the back, all of which can be locked in for forward power.

On the left, the steel shields can be seen in their lowered, defensive position.

Hydraulic-powered stabilizing spikes mounted on the outside of the font sides of the vehicles anchor TIV2 in place as it prepares to encounter a storm.

The spikes can embed 40 inches into the ground and prevent the vehicle from being pushed along the ground by a tornado's winds.

Marcus Gutierrez, a Navy veteran and first-class medic trained in trauma, is the driver of the TIV2.

Casey says that Gutierrez's medical training could be an asset to the team should anything go wrong, but his skill as a driver helps ensure that nothing does.

Aside from maintaining the team's health and safety, Gutierrez frequently provides aid to local victims of storms who, unlike the TIV2 team, did not intend to be in the path of destruction.

A rear view of the TIV2 shows the rear shield in its raised position, as well as the roof-mounted tower, which carries an array of monitoring tools.

This is the center-mounted swivel seat from which filmmaker and champion storm chaser Sean Casey operates the Imax camera, which extends up into a rotating turret.

Inside the TIV2, Sean Casey demonstrates the Imax camera mount, which he built from old WWII oxygen canisters.

Using two canisters, Casey welded a custom ball head with which he can adjust the camera's level, then lock it into place with hydraulics--flexibility that becomes important when the vehicle crosses uneven terrain.

The custom Imax camera mount Casey built rises up into a 48-inch-tall turret.

An open window allows the lens from the camera to stick out, but lets in all kinds of debris, Casey says. The team always wears helmets and goggles for protection.

Skateboard wheels are used as bearings to allow the turret to spin. The housing can rotate 360 degrees, giving Casey the freedom to get the shot he needs.

This shot shows the outside of the vehicle's custom rotating turret, which houses the Imax camera lens viewing hatch.

Essentially, Casey said, the TIV2 was built around the specifications of the camera. Since the camera is 40 inches wide, the turret had to be 48 inches wide to accommodate it, which in turn determined the size of the ceiling.

In order to be street-legal, the vehicle had to be less than 140 inches wide, as well as have headlights, turn signals, and mirrors.

An Imax camera and film canister rest in the rear of the TIV2.

Casey and his team spend about 70 days a year chasing storms during tornado season. In that chase period, he says, the team will encounter about 25 tornadoes and will successfully position themselves directly in the paths of about 2.

TIV2's license plate frame reads "DO NOT FOLLOW DURING ADVERSE WEATHER."

A view of the driver and passenger seats of TIV2.

The TIV2 is seen parked outside the Tech Museum in San Jose, Calif., where it stopped for a visit to promote Tornado Alley, the Imax movie the team filmed aboard the sturdy vehicle.

Casey says he already has plans to build a more low-profile third generation of the Tornado Interceptor Vehicle, which he hopes will shrink to a mere 4 feet tall.

Looking a bit like a futuristic military vehicle, Sean Casey's TIV2 is seen here with its steel shields lowered and its doors open.

The red bar is one of the 40-inch hydraulic stability spikes that hold the vehicle in place as the devastating storms pass over it.

Although Sean Casey has successfully built his vehicle to withstand the force of these violent storms, he wants more. With the next-generation vehicle already in the works, Casey has begun dreaming up the one that follows--and says a full range of motion would allow him to shoot straight up into the tornado as it passes directly overhead.