Last night, Juan Pablo Montoya lost control of his race car at the Daytona 500 and crashed into a pickup truck with a jet engine and 200 gallons of jet fuel, igniting the track in a superheated mess. But why the hell was there a helicopter engine strapped to a truck in the middle of a race?
Simply, the "jet dryer" trucks dry the track in wet conditions so that the racing surface doesn't get too slick. They've been around since the 70s, and were invented by racing luminary Roger Penske. We've talked about them before. They also clear out loose debris, since even a relatively small piece of junk can cause a crash at 200mph. They're powered by surplus helicopter jet engines, and sent out in large groups, at varying speeds, when the race is under a caution flag.
A fleet of seven or so jet dryers can take a soaking wet track to raceable condition in about two hours. That's about as big as the crews get, since the cost to assemble and fuel that many jet engines is prohibitive. Usually, the dryers coming out is a sign that you're in for a boring stretch—literally watching asphalt dry—not a fiery disaster that almost melted away the racing surface. Although in rare cases, the dryers can be cranked up so high that they blow the asphalt right off the ground, which actually happened in 2008.
And of course, when a fast-moving vehicle filled with gasoline careens into one of these trucks, filled with up to 200 gallons of jet kerosene, bad things tend to happen.
The trucks can also be used for snow removal at tracks, or in parking lots or airports. In addition to being a giant freaking snowblower, the heat from the engine can melt ice from up to 40 feet away.
Naturally, the Soviet version is a steampunk circus show, with Klimov VK-1 engines from actual MiG-15 fighters strapped to the trucks, probably due to all the Sasquatch. The heightened jet exhaust on these trucks is so that they can de-ice planes as well as runways. [Jet Dryers, NASCAR, DarkRoastBlend]