DAYTONA BEACH, Fla. -- The only vehicles allowed on the Daytona International Speedway track Sunday puttered along at about 20 mph and blew hot air, not noxious exhaust.
But not a single race car could move in the Daytona 500 until the 10 Jet Dryers -- a hybrid of truck, airplane and hot-air blower -- did their job. In the end, the large, loud vehicles that blow and boil the water off wet racetracks lost the battle, at least for this day.
Unlike football, baseball or even golf, racing cannot take place if there's even a drizzle. The combination of slick race tires, a steeply-banked track tilted at 31 degrees in the corners and moisture simply do not mix.
It's not a mater of macho. A driver attempting to drive a race car on a wet track at any speed would simply slide sideways once it hit a banked turn. And if tires with tread on street-legal cars hydroplane on slick public roads, imagine what a race car would do.
As a result, it's not enough to merely let the sun dry a track out. The Jet Dryers, brought to NASCAR in 1976 by legendary team owner Roger Penske, use a 1950s-circa jet engine to blast air at temperatures around 1,100 degrees onto the racing surface to dry it out in as little as 90 minutes -- provided it stops raining.
That never happened enough Sunday. The Jet Dryers came out twice, and rain chased them back in both times. In the absence of actual racing, fans lined the fences when the Jet Dryers were out and watched them amble along, albeit loudly.
The rain won, mainly because it wouldn't stop, and then stay away.
"[The rain] needs to stop before we can begin the process of drying," said NASCAR president Kim Helton. "We are equipped. The Daytona International Speedway has every piece of drying machinery they've got across the country here today."
The Jet Dryers, mounted on pickup trucks and using a Westinghouse J34 jet engine, have been in use since the 1970s for road construction. According to NASCAR historians, Penske was at the Michigan International Speedway one day in 1976 and saw a crew using the dryers to melt snow in a trench that had to be filled with stones as part of a paving project.
Penske then asked MIS director of facilities Dan Salenbien, who had a reputation as a master mechanic, if the vehicles could be used to dry out race tracks.
Prior to that, all tracks could do was let Mother Nature run her course with rain stopping and sun drying, or get every vehicle available -- pickup trucks, trailers, emergency vehicles, even street cars -- and run them around the track to hasten the drying process. But races still had to be run or finish on Mondays more frequently than now.
Salenbien had to modify the dryers for use on race tracks. Among the changes: he mounted them on a frame, put the apparatus on the back of Chevrolet trucks with four wheels on the rear and devised a hood to direct the hot air directly onto the racing surface. The same engines are still used as in 1976, at a current cost of $15,000 apiece.
The entire cost to build one Jet Dryer is around $60,000.
The Jet Dryers are loud, audibly louder than race cars when passing. They also run on a variation of kerosene jet fuel, with the 200-gallon tanks burning their entire load in one hour. According to NASCAR, there was a race at MIS in 2007 in which nearly 15,000 gallons of fuel were used to dry the track after two days of rain.