RECREATION : Setting Sail--on Ground? : Land yacht users can reach speeds of almost 80 m.p.h. and get ‘an adrenaline rush that can’t be beat.’

Visitors to Mile Square Park are sometimes surprised to discover that those colorful sails in a distant part of the park are not attached to sailboats, but to land sailers speeding along on an old runway.

They may also be surprised at how fast the crafts can move.

They “have gotten so fast (in the six years) I’ve been doing it, that it’s too dangerous to let ‘em go full speed at Mile Square Park,” says Chris Hansen, 42, of Orange. Hansen has a machine shop and designed and built his own land yacht, which has a sheet metal body.

While sailboats can go no more than the speed of the wind, able pilots can get land sailers up to speeds as much as five times the speed of the wind. Speeds of almost 80 m.p.h. have been reported on dry lake beds, which have an ideal surface for the sport.

Land sailers are kept to much more moderate speeds at the park, where a triangular-shaped runway area has one leg devoted to land sailing. The park is really the only place in Orange County to sail the crafts. Otherwise, land yacht pilots must go out to the desert.

The exhilarating speed makes land sailing “comparable with a roller coaster ride which you can extend as long as you wish,” says pilot Robert Weber, 51, of Huntington Beach. Weber is an auto mechanic who also designs his own crafts.

Land yachts or land sailers come in a wide range of designs, materials and sizes--with wheelbases from 8 feet to 30 feet. The most common sizes, however, are 8 to 12 feet.

Basically, land yachts have a triangular frame and three wheels (different kinds for different terrain). The front wheel is steered by foot pedals and the rear axle has two wheels. There’s a seat for a pilot (though some have room for a passenger too) and a mast with a sail and a boom maneuvered with a rope.

Pilot-designers strive to make land yachts lighter and stronger by using modern aerospace materials and aerospace structural design techniques, according to George Enzmann, 68, of Fountain Valley, a retired aerospace engineer.

One of the more unusual concepts is to use a fixed-sail or “wing.” Enzmann is currently designing a land yacht with a fixed-sail made of fiberglass composites. The fixed sail will have a flap on it to provide camber--curvature--at low wind speeds, Enzmann says.

Used land yachts are available for from about $500 to $2,000. New ones can cost as much as $15,000 to $20,000.

Land sailing may look the same as water sailing, but that’s where the comparison ends, Weber says.

The crafts are started by pushing and then the pilot jumps in.

“Once a land yacht is in motion, one has to think airplane, with all the technical aspects related to it,” Weber says, “because you always travel faster than the actual wind speed. Just think of a vertical wing, instead of horizontal.”

The wing of a glider or an airplane will float, whether you go with the wind or against it, Weber explains. “That means the lift of a wing on a glider is transferred into a forward motion on a land sailer.”

Weber says the big difference between a sailboat and a land sailer is “that you have a lot of drag involved in a sailboat, while a land sailer has little in comparison.”

The sail on a land sailer is kept close-hauled--tight to the boat--both upwind and downwind, according to Hansen.

“Since the land sailers can go faster than the wind, we take a zig-zag course both up- and downwind,” Hansen says. “And the sails are trimmed basically the same, where on a sailboat, you would let your sails way out to go downwind.”

Ice boats--land yachts with skates instead of wheels--are thought to have originated in the Netherlands centuries ago. Today, they go well over 100 m.p.h.

Land sailing may have started with the Chinese and the Egyptians, who are thought to have created chariots with sails.

A Flemish engineer, Simon Stevin, is reported to have built a large sand sailer with two masts for beach sailing in about 1600. By the 1800s, more inventors were experimenting with vehicles for sand sailing. But sand and land sailing didn’t really catch on until after World War II.

The North American Land Sailing Assn., formed in 1972, includes representatives from seven sailing clubs around the U.S., including Pacific Landyacht Club, according to Elizabeth Braslow, 39, secretary of the club and a resident of San Pedro. Club dues are a modest $15 a year for singles and $20 for families.

About 85 people belong to this club and many of them sail at Mile Square Park, according to Braslow. She shares a land sailing passion with her husband, Jim, 45, who is president of the national organization.

Pacific Landyacht Club is the largest club in the country and includes members from as far away as Canada, according to Elizabeth Braslow, who is also treasurer and secretary of N.A.L.S.A. There are even a couple of members in France, who represent the Pacific Landyacht Club at European races when U.S. members can’t attend.

The largest gathering of land sailers in the country was recently held at Ivanpah Dry Lake, near Stateline, Calif. The event was the America’s Cup land sailing meet held annually during Easter week.

The national organization also hosted the 1990 U.S.A. International Land Sailing Championships at Ivanpah, with entrants from the United States, Australia, New Zealand, England, France, Sweden, Denmark, Wales, Denmark, Belgium, Germany and the Isle of Jersey.

For races, boats are divided into classes, based on the size of sails, according to Jim Braslow, who often sails with his floppy-eared sable German Shepherd named Teddy. Races may be a set number of laps or a duration of time and consist of navigating around a series of marks.

What’s the attraction of land sailing?

“An adrenaline rush that can’t be beat,” says Hansen. “It’s the most thrilling thing I’ve ever done. It’s spoiled my sailboat sailing . . . . It spoiled my motorcycle hobby, go-carts, Baja bugs . . . . I’ve tried several different hobbies and this one is really enticing,” Jim Braslow says.

“It’s hard for me to understand why the sport is not just tremendous, huge. It is so thrilling to go 60, 70, 80 miles an hour, even, in these boats with no power but the wind,” he says.

How hard is it to learn?

Some pilots say people knowledgeable about water sailing can usually pick up the fundamentals of land sailing fairly easily. Weber, however, says such knowledge is a handicap, because “once the land sailer gets moving, it has nothing to do with sailing.”

Elizabeth Braslow says, “It’s easy to learn and it’s hard to perfect.”

“You spend the rest of your life learning new techniques, trying new things,” she says. “There are always new innovations in sail cloth, sail material, different wheels, different ways to adjust it, different tactics on how to beat out someone else, if you’re into racing. It’s really an ongoing project.”

For more information on land sailing, call Elizabeth or Jim Braslow at (213) 437-8585.