Boeing and Airbus each capitalized on the continued robustness of global narrowbody demand on Thursday, with a pair of big orders for members of their respective single-aisle families. Boeing’s contract with Riga, Latvia-based low-fare airline Primera Air calls for a firm order for eight 737 Max 9s to accompany a lease deal involving Air Lease Corporation covering another eight of the new jets. Airbus’s deal with Delta Air Lines covering 30 A321s adds to the U.S. carrier’s previous orders totaling 82 of the CFM International-powered jets.

Boeing sees the Primera Air contract as particularly significant given the carrier’s intention to fly the airplanes on transatlantic routes between Europe and North America, in a plan evocative of the transatlantic Boeing 787 operation of fellow European low-fare airline Norwegian Air. Primera Air plans to use the Max 9’s auxiliary fuel tanks to boost the range the airplanes need to connect Europe to the east coast of the U.S. Now flying nine 737-700s and 737-800s to 70 airports in Europe, Primera Air also took purchase rights for another four Max 9s as a contingency for further expansion of its planned transatlantic operation.

For Airbus, Delta’s decision to order more A321s means a still stronger backlog for its final assembly facility in Mobile, Alabama, which builds most of the A320-family airplanes destined for U.S. carriers. Airbus expects the Mobile plant to build A321s and A320s at a rate of four per month by the end of the year.

Delta, which now flies 19 A321s, expects to take all 112 of the airplanes on order by 2021. It said it plans to deploy most of the airplanes on domestic U.S. routes as it retires older, domestic-gauge airplanes from its fleet over the next several years.

Separately, Delta confirmed Thursday that it will defer 10 of its planned 25 A350-900 deliveries scheduled for 2019 and 2020 by two to three years. Delta’s delivery schedule for its first A350-900 remains in place and the airline plans to operate its first A350 revenue flight in the fourth quarter.

“These agreements better align our widebody and narrowbody orderbooks with our fleet replacement needs,” said Delta COO Gil West. “We appreciate the partnership of Airbus, Rolls-Royce and GE Aviation as we exercise what’s best for our business, our employees and our customers.”