The world’s commercial fleet will double to almost 40,000 aircraft by 2031, with the bulk of this growth in the Asia-Pacific region, Air Lease Corp. founder Steven Udvar-Hazy said Sept. 18 at the Boyd Group International Aviation Forecast Summit in Dallas.

Of today’s in-service fleet, only about 5,000 aircraft will be operating in 2031, so 13,000 aircraft will be needed to replace existing fleet, said Udvar-Hazy. Another 19,000 aircraft will then be needed to accommodate a 5% annual growth in passengers.

The percentage of the fleet owned by lessors will grow to about 50% in this period, up from under 40% today, Udvar-Hazy added.

The composition of the world’s fleet also will change, according to Air Lease’s founder, with mainline carriers continuing to abandon 50-seat regional jets in favor of a capacity floor of 140- to 150-seats. This creates a gap between 50-seat and 150-seat aircraft, which Udvar-Hazy says will be filled in part by large turboprops being developed by ATR and Bombardier, and 70- to 120-seat regional jets.

By 2031, single-aisle aircraft will comprise about 70% of the global fleet, while “mid-size widebodies” such as the Boeing 787 and the Airbus A350 growing to 23%, adds Udvar-Hazy.

But several worrying trends could depress airline growth, Udvar-Hazy warned. Industry is in need of more than 500,000 new pilots by 2031, which will be challenging, while taxes and regulations, particularly in the developed world, have become “burdensome,” says Udvar-Hazy.

Airport fees worldwide also are “rising too fast,” he continued, adding that airport infrastructure in mature markets is limited. “It is just too hard to build new airports in the West,” said Udvar-Hazy.