Delta Air Lines said Tuesday that it had placed firm orders for 30 additional A321neo aircraft with Airbus, adding to its existing orders with the European planemaker.The order comes as a follow-up to an order announced in April for 25 of the A321neo jets, along with an additional 25 options — the newest announcement converts those options into firm orders.Want more airline-specific news? Sign up for TPG’s free new biweekly Aviation newsletter!Delta now has a total of 155 A321neos on order, with options for 95 more.The current order also follows an agreement Delta announced in July to purchase 29 used Boeing 737-900ER narrow-body jets (along with leases for seven used Airbus A350-900s).The A321neo fleet will be the first to feature Delta’s new domestic first-class seat, which will feature a memory foam cushion, increased privacy, extra storage and a larger tray table compared to the current domestic first seats.Sign up for our daily newsletterEmail addressSign upI would like to subscribe to The Points Guy newsletters and special email promotions. The Points Guy will not share or sell your email. See privacy policy.An image of the new first-class seats Delta plans for its new Airbus A321neo aircraft. (Photo courtesy of Delta Air Lines)The new planes will feature 20 first-class seats, 42 Comfort+ extra-legroom seats, and 132 seats in main cabin for a total capacity of 194 passengers.Delta currently operates 121 Airbus A321neo aircraft, the previous generation. Those aircraft seat 191 passengers, with 20 first-class seats, just 29 Comfort+ seats, and 142 seats in the main cabin.More: United unveils massive aircraft order, announces new narrow-body cabin interiors and retrofit programThe airline said it expects to take delivery of its first A321neo in the first half of 2022. The aircraft were initially expected to begin arriving in late-2020. However, the coronavirus pandemic has led to delays across supply chains and manufacturers, while diminished travel demand has made airlines reluctant to take too many deliveries until travel begins to pick back up.