Air Lease has confirmed a $1.2bn order with Boeing for four 787-9 Dreamliners, with an option to buy four Next-Generation 737-800s, marking the completion of an agreement announced during the Paris Air Show in June 2011.

The new aircraft will join the 74 Next-Generation 737-800s and five 777-300ER planes that Air Lease currently has on order.

Air Lease Corporation chairman and CEO Steven Udvar-Hazy said the order will continue to diversify the company’s portfolio of efficient aircraft.

"The 787-9, with its increased size and range, will provide our customers with the ability to serve more cities with the lowest possible cost per seat," Udvar-Hazy said.

The request increases the number of 787-9s on order to 270 from customers located all over the world, while the 787 Dreamliner family has a total of 825 orders, according to Boeing.

Boeing Commercial Airplanes senior vice-president for sales and customer support Ray Conner said the 787-9 Dreamliners and 737-800s support the company’s strategy of establishing a fleet of young, high-quality, high-demand planes for its airline customers.

The 787-9 aircraft is a bigger version of the 787-8 with the capacity to seat 250-290 passengers and a range of up to 8,500nm (15,750km).

The 787 offers exceptional environmental performance and uses 20% less fuel than similar aircraft.

Similar to today’s fastest wide-body airplanes, the aircraft can travel at a speed of Mach 0.85.

Boeing Commercial Airplanes vice-president of leasing sales Bill Collins said Air Lease’s order helps establish the 787-9 Dreamliner in the leasing market and also builds on the continued market success of the plane.