Traffic was up in May at some of the busiest airlines that serve Wichita’s Mid-Continent Airport. According to a report from the Atlanta Business Chronicle, Delta Air Lines Inc.’s overall system traffic — also known as revenue passenger miles — was up 2.7 percent in May compared to a year earlier. Load factor, or how full its planes were, was up 1.6 points to 83.9 percent.

Domestic traffic went up 0.3 percent and international traffic fell 6.7 percent. Delta (NYSE: DAL) flew 13.8 million passengers, up 0.5 percent from May 2009.Locally, the airline has seen some gains in passengers when compared to 2009. Reports for May weren’t available Friday for Mid-Continent Airport, but between January and April 2010, Delta carried 59,946 passengers to or from the Wichita airport. That’s up from 57,834 during the same time period last year.

AirTran also has seen some improvements nationwide, though local numbers don’t necessarily match that pattern.

The Baltimore Business Journal reported that system-wide traffic for the airline jumped 8.4 percent to 1.67 billion in May. Load factor rose 2.8 points to a record 80.8 percent in May.

Passengers flown surged 6.6 percent to 2.1 million.

Year to date, AirTran’s traffic was up 7.8 percent, its load factor was up 1.5 points and the number of passengers flown grew 4.3 percent to 9.7 million.

However, at Mid-Continent, AirTran had a total passenger count of 32,796 between January and April of 2010, down from 37,492 during the same time period in 2009.

Mid-Continent’s busiest airline, American Airlines, saw a companywide traffic increase of 4.1 percent, according to a news release from the airline.

American has been showing local improvements, too, with 76,705 passengers between January and April this year. In the same months last year, the airline carried 64,346 passengers.

Mid-Continent had 448,229 total passengers from January to April of this year, up 4.36 percent over last year’s 429,517 total for the same time period.

In April 2010, the airport had 116,538 passengers, up 3.95 percent over last April’s 116,538 passengers.