ed up with airport security checks so lengthy that he missed two flights, Doug Mayer grounded himself. Mr. Mayer, a computer-network engineer, now drives on almost all business trips in a Ford Explorer that he outfitted with mobile file storage, a portable desk, wireless laptop and printer.

"I've got three sets of plane tickets sitting here unused because we just won't fly," said Mr. Mayer, president of MobileNet Inc., a company in West Chester, Ohio, that designs and builds remote-access computer networks. "I'm a true road warrior."

So are many other business travelers who have switched to driving since Sept. 11. They say that the difficulty at airports is not worth it, and some are still uncomfortable flying. Tammy Troilo-Krings, owner of the travel-management company Troilo & Associates in Westerville, Ohio, says that the balance is tipped toward driving on trips that involve a flight of three hours or less.

"If getting to the airport takes 20 minutes, and you have to be there two hours prior to departure, and have to deal with all the security issues, you could have left home and already be at your destination," Mrs. Krings said.

The switch to driving is inspiring travelers to install wireless laptops and portable desks so they can get work done along the way. They are leasing motor homes that come equipped with swivel chairs, desks and even showers. And some are taking new city-to-city limousine services that charge flat, rather than hourly, rates.

Donald Resnick, a real estate developer, has taken a limousine twice in the last six months between Philadelphia and New York, and found the service, operated by Carey International, to his liking.

"I can get a lot done, and they pick me up at my front door," said Mr. Resnick, president of the Acorn Development Corporation in Oaks, Pa. "I did it strictly for convenience, and it's comfortable. Plus, you don't get to New York and have to get a cab."

Some cities see opportunity in the shift to ground transportation. Charleston, S.C., for example, is among the regional hubs that are promoting themselves to businesses within a five-hour drive. And companies are noticing a swing toward regional rather than national conferences to give employees and clients the option of driving.

At least a third of clients of Aspen Productions Inc., an Atlanta meeting-planning concern, are giving up a national event in favor of six or seven regional meetings with the same agenda, said Pete Foley, director of operations.

If recent surveys are any indication, the trend is here to stay. Nearly 60 percent of 800 business travelers polled in January by Yesawich, Pepperdine & Brown, a research firm in Orlando, Fla., said they would drive rather than fly whenever they could for future business trips. And nearly 30 percent of 1,000 workers said in February that their companies now required or recommended driving instead of flying on business trips, according to the Travel Industry Association of America. High gasoline prices have not deterred business travelers from driving, corporate-travel specialists say.

Corporate travel managers surveyed by Runzheimer International say the time spent at airports is the main reason business travelers are switching to driving, with fear of flying a close second.

"They were always yanking us aside at the airport," said Mr. Mayer of MobileNet, recalling the frustrations he and his co-workers felt in recent months. "They'd take hours to go through our equipment."

He spent $800 to equip his company's vehicle with office equipment, and, with two employees, drove seven hours in February from their offices outside Cincinnati to St. Louis to visit a client. In January, he and three engineers drove 10 hours to Kansas City, Kan., on business.

One product Mr. Mayer installed is the AutoExec, a mobile office desk with file storage made by GoOffice .com. While most people who buy the desk are salespeople or real estate agents driving daily across a territory, the Grand Rapids, Mich., company is getting more customers who are opting to drive longer distances for business trips, says Kevin Bart, national sales manager.

Whereas the company received three to four orders a month from such business travelers six months ago, it now gets three to four a day, Mr. Bart said. "Our marketing campaign for the second half of the year is going to try and go after those people," he said.

Limousine companies are also taking steps to capture the new market of business travelers who drive. Arthur Rento, president of Pontarelli Group Charter, a limousine and bus charter company in Chicago, had a tough time before Sept. 11 renting out his company's LandJet, a chauffeured van equipped with cellphones, laptop ports, printer, fax and bar. "You'd have to twist them into it,'` Mr. Rento recalled.

Now, the LandJet, which costs $75 an hour plus tolls, tip and phone charges, is booked nearly every day, compared with one or two bookings a week previously. Mr. Rento is also outfitting his 24 Lincoln Town Cars with laptop desks and offering four laptops for use in the cars.

After Sept. 11, some limousine companies created services that offered flat, rather than hourly, rates between cities. BostonCoach of Everett, Mass., charges about $450 for a one-way limousine trip from Boston to New York, compared with $738 before Sept. 11. The new fares are competitive with last-minute business air fares, but the ability to work while traveling is the real attraction for many executives.

"At the airport, it's hard to be productive anymore," said Dick Mayo, chairman of Mayo Capital Partners in Boston, who has used such limousines several times in recent months. "When using a limousine, I'm working within five minutes and I work until my destination."

Rented motor homes and coaches, outfitted for business travel, are also attracting business travelers. The Custom Coach Corporation in Columbus, Ohio, has experienced a 25 percent increase in business rentals for its nine lease vehicles in the last three months, according to Julie Olds, leasing coordinator.

Business travelers don't sleep onboard such coaches, which are equipped with kitchens, bathrooms, showers and meeting tables but lack beds. Motor homes include beds, although some travelers prefer to stop in hotels for the night on long trips.

Some corporate executives may have defected to the road for good for short trips, especially if they were always wary of flying. Others, however, can't wait to get back in the air.

"I would rather fly, and I'm driving now," said James C. Monroe, design director for Gale Sliger Productions, a special-event design and production firm in Dallas. "I even have motion sickness. I also don't want to wait around the airport for two and a half hours. The wait at the airport is swinging the balance."