How Delta profits off of one of the oldest fleets in the U.S.

A jetliner parked in a cavernous hangar here boasts a gleaming paint job, 160 pristine blue leather seats and a new-airplane smell. But this latest addition to the Delta Air Lines Inc. fleet isnt new.

Not by a long shot. The twin-engine MD-90, acquired from China Southern Airlines Co., is more than 13 years old. It is one of 49 used McDonnell Douglas MD-90s Delta is rehabbing after scooping them up from global airlines that were thrilled to get rid of a plane that no longer is built by a manufacturer that long ago was taken over by Boeing Co.

Most large carriers prefer fuel-sipping new planes with the latest high-tech gadgetry. But Delta, which has one of the oldest fleets in the U.S., is making a habit of succeeding by zigging when its rivals zag.