ATLANTA (Bloomberg) — Delta Air Lines Inc., the world's largest carrier, said its private-jet unit acquired closely held Segrave Aviation to reach more customers who want to fly on their own schedules.

Buying Kinston, North Carolina-based Segrave will double the size of the Delta AirElite fleet, Delta said today in a statement. That division now operates 15 planes, according to JetNet data reported by Aviation Week Intelligence Network.

The purchase was a cash transaction, Atlanta-based Delta said, without disclosing the terms.

Delta bills itself as the only US-based airline with commercial and private-jet service. Passengers on Cincinnati- based Delta AirElite, founded in 1984, earn benefits on the company's frequent-flier programme, according to the airline.