Delta may be about to make its second billion-dollar aircraft order this month

Delta Air Lines is reportedly close to another multi-billion dollar airplane order.

According to Reuters, three sources familiar with the matter say Delta is close to a deal for 37 Airbus A321ceo or “current engine option” jets.

This comes just days after news broke that the airline is also close to a 75-aircraft order for Bombardier’s C-Series.

At list prices, the 37 jets have a total value of $4.25 billion.

However, with Airbus looking to fill out its production slots before the next generation A321neo arrives, Delta is likely to have negotiated a very substantial discount.

The rumored deal would be the third substantial order Delta has placed with Airbus in recent years, and the second for the A321ceo.

“No decision has been made on an aircraft order,” a Delta spokesperson told Business Insider.

Representatives from Airbus were not immediately available for comment.

The A321s from this order will likely be deployed as a more fuel-efficient alternative to Delta’s fleet of almost 120 aging Boeing 757-200 jets.

The Atlanta-based airline currently boasts a fleet of 809 mainline jets from Airbus, Boeing, and McDonnell Douglas with an average age of 17.1 years.

Delta looks to be keen to bring its fleet age in-line with its fellow legacy carriers American — which is at 11.2 years of age — and United — at 13.6 years.

In 2013, Delta ordered 30 A321s along with 10 A330-300 wide-body jets from Airbus. The first A321s from that order is expected to debut next week in Atlanta.

In late 2014, Delta returned to Airbus for a batch of 50 wide-body A350-900XWB and A330-900neos with a list value of more than $14 billion.

In recent years, Delta is earned a reputation for being highly effective at searching out and taking advantage of undervalued assets. In the mid-2000s, as others dumped their fleets of McDonnell Douglas MD-80/90 jets in favor of newer, more fuel efficient models, Delta picked them up second-hand for pennies on the dollar.

With the A321ceo nearing the end of its production life, it may have been the bargain Delta is looking for.