(FORTUNE Small Business) – A record level of flights were delayed or canceled this past holiday season, and experts believe our nation's aviation woes are going to get worse, especially for rural entrepreneurs. Since July 2001, 43 U.S. airports serving small and medium-sized cities have lost all scheduled service because the airlines are cutting out less profitable routes, according to BACK Aviation Solutions, a consulting firm based in New Haven. "As airlines try to find ways to return to profitability, the smaller routes become less important," says Michael Allen, co-founder of BACK. For nonmetropolitan entrepreneurs, losing service could result in higher transportation costs for importing and exporting goods and more time wasted on the road. According to Allen, the airports most likely to see service cuts in the future are those dependent on one or two hubs and those served by only one airline (out of 119 of these airports, the 67 located in the most populated areas are highlighted). As an extreme example, FSB zeroed in on Grand Forks, N.D., to show the traveling options a business owner might face should the Grand Forks International Airport close. --MAGGIE OVERFELT