According to the May report, the most recent month available, the Atlanta-based carrier served 48.6% of the 53,632 passengers who boarded flights at the Midlands airport.
Overall, the number of passengers who flew out of Columbia on Delta planes totaled 26,039 in May, a 12.59% increase over May 2015, the airport reported.
Delta’s year-to-date share of passenger traffic at Columbia was 48% through May, up from 44% in May 2015 and 43% in May 2014, according to the report.
“Consistent with our strategy of adding more mainline flights, Delta offered nearly 4,000 more seats from Columbia in May 2016 as it did in May 2015,” a Delta spokeswoman said.
The additional seating is the result of the company’s efforts of “upgauging” 50-seat regional aircraft to larger mainline aircraft such as the Boeing 717, which typically seats 110 passengers, and the 149-seat MD 88, said Dan Mann, airport executive director.
Delta reported that in May it served Columbia with 309 flights and a total of 29,100 seats compared with 292 flights and 25,600 seats for the same month in 2015.
Meanwhile, United Airlines’ share of market through May shrank to 17% compared with 18% for the first five months of 2015, and American Airlines, which last year completed its merger with US Airways, saw its share of market drop to 35% in May compared with 38% for the same month in 2014.
In May, American recorded a 2.1% drop in enplaned passengers, boarding 18,683 travelers compared with 19,083 for May 2015. Meanwhile, United saw its passenger enplanements in May slip 1.72% to 8,910, according to airport statistics.
Year-to-date, all three carriers serving Columbia have recorded increases in passenger boardings. Through May, American is up 8.06% to 90,838; United is up 3.70% to 39,401; and Delta is up 5.91% to 100,618.
Overall, the number of passenger enplanements rose 4.39% in May compared with the same month in 2015. Year-to-date, passenger enplanements are up 6.01% at 230,857 compared with 217,773 for the first five months of 2015.