(FORTUNE Small Business) – Like many other suburbanites around Portland, Ore., 64-year-old Dick VanGrunsven commutes to work every day. Unlike most of them, he never gets stuck in traffic. Each morning he climbs into an airplane he designed himself, taxis to the end of a grass airstrip, and takes off over a lush landscape of hazelnut trees, horse farms, and winding rivers. The 30-mile trip goes quickly, and soon he's touching down on the runway abutting his company's 63,000-square-foot factory. He usually starts the workday early, but as founder and CEO of Van's Aircraft, he can take a break and go for a spin in a new plane anytime he wants. "I like my job," he says. "There aren't many like it around."

Van's, based in Aurora, Ore., sells airplanes in kit form. The company produces seven VanGrunsven designs, all sleek, single-engine sport planes capable of speeds near 200 miles per hour. Yet its greatest technological achievement lies in the computerized production technology behind the airframes. "It's changed not only how quickly we do things but how we do things," VanGrunsven says.

Over the past two decades computer-aided design and manufacturing (CAD/CAM) has all but replaced manually operated machine tools in U.S. factories. Today's desktop computers are powerful enough to run design software that once required $200,000 mainframes. That makes the technology affordable not only for small companies in the aircraft industry but for makers of everything from breadboxes to heart valves. The design data flow to automated machine tools that stamp, bend, or mill the desired parts with an otherwise impossible degree of precision, speed, and consistency. "You can't be competitive, paying American wages, if you don't have these technologies," says Steve Wolfe, publisher of the online trade journal CADCAMNet.

Van's engineers use mechanical Desktop, a CAD/CAM application sold by Autodesk for around $5,000 per user, plus upgrade costs every couple of years. (Autodesk's competitors in the light-manufacturing space include Catia from IBM, Pro/Engineer from PTC, and SolidWorks from SolidWorks Software.) The software has helped Van's become the world's leading producer of kit airplanes. Kit makers fabricate the parts and ship them to the buyer, who assembles them and, not incidentally, takes on legal responsibility for the plane as its manufacturer. Van's most popular model, the RV-7, sells for $17,000, with the engine and other components adding another $40,000. A comparable factory-built plane costs two to three times as much.

The kit-aircraft sector hardly existed when VanGrunsven started cobbling together his first airplane at his parents' farm in the late '60s. But in the early '80s product-liability lawsuits and the economic downturn nearly scuttled light-airplane makers such as Cessna and Piper. Kit manufacturers stepped in to fill the void. Today nearly a quarter of all general aviation aircraft are home-built, and Van's, with $30 million in sales, has 20% of the market.

Traditionally, the most difficult part of the kit-building process has been fitting the airframe parts together accurately and then drilling holes to bolt them in place. But Van's kits are now shipped with the holes already drilled, cutting the amateur builder's work by an estimated 30%. (Current assembly time: around 2,000 hours for a standard kit.) "And we match the holes, so there's only one way to put them together," says chief engineer Ken Kruger.

Van's business has doubled in the seven years since it adopted the new technology, and profits are up more than 25%. Soaring demand prompted the company to order another punch press this year. In September the company will ship out the last parts (canopy and cowling) for its first four-seat model, the RV-10. But despite all the fancy engineering, a close inspection of the prototype's tail reminds us that VanGrunsven started building airplanes in a barn with tools no more sophisticated than a hacksaw. There, stuck to the base of the rudder with clear plastic tape, is a two-inch-long triangle of wood scrap. "A makeshift trim tab," VanGrunsven explains with a shrug, "until we get around to making a real one."