Rapid City Regional Airport saw a 21 percent surge in airline traffic during October and November, due in part to the entry of a new airline in the Rapid City market.

Frontier Airlines, the Denver-based low-fare carrier, began twice-a-day service between Rapid City and its Denver hub on Oct. 5. So far, 8,885 passengers have taken advantage of the new service.

Frontier's price-cutting extended to existing airlines such as United and Northwest. The carriers matched Frontier on many routes, and the net effect was lower overall fares to a number of destinations.

Air travelers took advantage in a big way. In October, 45,642 passengers flew into or out of Rapid City. That was a record for October, and a 21 percent increase over October 2006. And in November, 41,230 flew out of Rapid City, also a November record and a 21 percent increase over November 2006.

Meanwhile, on Nov. 21, existing low-cost carrier Allegiant Air added a nonstop flight to the Phoenix-Mesa area. That new route, along with more frequent flights on its existing route to Las Vegas, helped Allegiant post a 40 percent increase in November compared with the period in 2006.

Before Frontier hit the market, there were concerns the new carrier would take passengers away from the other carriers. But the numbers show all but Northwest Airlines increased their passenger loads. And Northwest's dip in traffic was fairly small.

The October-November totals, compared with the same two months of 2006, were:

n SkyWest/DeltaConnection to the Delta Airlines hub in Salt Lake City: 13,354 passengers, up 6 percent.

n Northwest Airlines to Minneapolis: 28,218 passengers, down 3 percent.

n United Express service to United Airlines hub in Denver: 31,289 passengers, up 19 percent.

n Allegiant Air's direct service to Las Vegas and Phoenix, 5,126 passengers, up 32 percent.

Rick Kahler, a Rapid City author, speaker, financial planner and frequent flier, said Frontier's entry into the local market has been a boon for business travelers. He said fares here have plummeted, and travelers now have more choices.

He recently had a speaking engagement in Los Angeles, and because of his schedule he had to fly to Los Angeles and back the same day. Delta Airlines' price was $1,250, but Frontier's price was $450. He flew Frontier.

For a January trip to Orlando, Kahler chose to pay $650 through Northwest Airlines rather than $450 through Frontier. Even though the ticket price is higher, Northwest offered frequent-flyer perks and travel vouchers from previous flights, Kahler said.

"It's not a given that I'm going to fly on the cheaper airline," he said.

Because of the increased passenger counts, empty seats are at a premium, according to airport officials. The average load factor - the percentage of seats filled by passengers - was a record 86.9 percent in October. The previous record was 85.9 percent, set in June.

So far this year, Rapid City passenger traffic is running 5.7 percent ahead of 2006. Airport officials expect 2008 to be a record year for Rapid City Regional Airport. The current record is 2005, when more than 507,000 people flew into or out of the Rapid City airport.

"We are very pleased to see such a positive response to the increased service that we have experienced over the past couple of months," said Mason Short, executive director of Rapid City Regional Airport. "We thank the users of our airport for taking advantage of these new connections."

With the new competition, Rapid City now has some of the lowest airfares in the region. That in itself could increase passenger numbers, because leisure travelers are often willing to drive to save money.

In the past, it was often worthwhile to drive to Sioux Falls, Omaha or Denver to garner lower fares. Now, depending on your destination, it might still pay to drive to Denver in some cases. But with lower local fares and higher gas prices, Rapid City Regional Airport will likely see less "leakage" of passengers to other airports.

It's unclear whether Rapid City's prices are low enough to entice Sioux Falls residents to drive across the state and book flights out of Rapid City. However, people in Chamberlain, Gregory or Pierre would be more likely to fly from Rapid City rather than Sioux Falls.

Despite the busy fall, Rapid City remains a summer market for air travel. June, July and August are the busiest air travel months here. More than 50,000 people per month fly to or from Rapid City during the summer.