Delta Air Lines Inc. will weigh adding a more fuel-efficient version of Airbus SAS’s narrow-body A320 to its fleet, historically dominated by Boeing Co. jets.

“Like everyone else, we’ll look closer at the A320 to see if it might merit deeper consideration for our long-term fleet plans,” Chief Executive Officer Richard Anderson said last night in a weekly recorded message to employees.

Airbus said earlier this week it will offer new engines for its single-aisle A320 aircraft series that can increase fuel efficiency by 15 percent. The planes, which will be available in 2016, compete with Boeing’s 737.

“We wish Boeing would do the same, but it doesn’t look like the 737 will have much innovation in the coming years.”

Boeing Commercial Airplanes CEO Jim Albaugh said in October that the business case for new engines is “not as compelling as we’d like to see.”

About two-thirds of Delta’s fleet at the end of September consisted of jets from Chicago-based Boeing and companies it has acquired. Delta gained Airbus planes when it bought Northwest Airlines Corp. in 2008.

Delta has repeatedly said that it doesn’t plan to purchase many new planes in the immediate future, and is instead spending $1 billion on its existing fleet to add flat-bed seats and first-class cabins.

Delta’s narrow-body jets include more than 100 MD-88s that are about 20 years old on average, about 50 DC-9s that are 34 years, and about 70 A320s that are 16 years old, according to a regulatory filing for the third quarter.

“While we’re pretty happy with our fleet today, we’re always watching changes in the capability of aircraft,” Anderson said.