(FORTUNE Magazine) – Feel like starting your own airline? Plenty of people do these days. Emboldened in part by the runaway success of low-cost, no-frills operator Southwest Airlines -- the most admired in its category (see Cover Stories) -- more than half a dozen new carriers have taken to the skies in the past two years. And the Department of Transportation has a dozen more applications pending. Conditions are optimum: With all the major players struggling to become more efficient, there are plenty of extra planes, pilots, and flight crews to be had for cheap. Plus, the Clinton Transportation Department has announced its intention to actively encourage startup carriers, a big change from the hands- off policy of the Republicans.

The busy New York-to-Florida market has drawn several of the startups. ''That's because of all the leisure travel on those routes,'' says Lee Howard, head of Airline Economics International in Arlington, Virginia. Vacation passengers naturally have a greater interest in bargain fares than passengers on business. Some rookies are stepping right into the cross hairs of big-time competitors. ValuJet, for example, a low-fare, short-haul carrier with a smiling cartoon plane for a logo, recently planted itself in Atlanta, home and hub of Delta Air Lines. With one-way fares on ValuJet starting at $39, Delta has been forced to cut its prices on competing routes. But some experts think such in-your-face strategy could well backfire. ''A startup carrier that competes for major mainline traffic flows is going to be short-lived,'' says Michael Boyd, president of Aviation Systems Research in Golden, Colorado. Boyd believes that the convenience of more frequent flights and the loyalty generated by frequent flier programs will always give a big carrier the edge. Not to mention its seeming readiness to suffer losses year after year. Predicts Boyd: ''The Southwest thing -- that's not going to be repeated.'' -- M.D.F.

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