MONTREAL, Canada (AFP) — Hundreds of thousands of pilots will need to be trained to meet growing demand for air transport around the world by 2036, the UN aviation agency said Tuesday.

International Civil Aviation Organisation (ICAO) secretary general Fang Liu said in a speech in Montreal that the number of commercial flights and passengers are forecast to double in the next 15 years, while the number of pilots and other airline workers is falling due to attrition.

Liu pointed to “the inevitable demographics of ageing populations, lowering birth rates, and other attrition factors” for the workforce contraction.

In addition, aviation is facing increased competition from other sectors “for up-and-coming talent,” she said.

“Aviation has to do a much better job of both attracting and retaining the skilled workers and managers it requires in the decades ahead,” she concluded.

The ICAO said at least 620,000 pilots will be needed by 2036 to fly commercial aircraft with 100 or more seats. Eighty per cent of those pilots have yet to be trained, it added.

“The story is the same with respect to the future air traffic controllers, maintenance personnel, and other technicians needed,” Liu said, adding, “These are just a few of (the) literally hundreds of direct and indirect aviation-related career categories which will be impacted by attrition-related trends.”

Driving the increase in air transportation is an increase in tourism and booming online retailing that relies on the sector to deliver its wares.

Some 4.1 billion people fly each year, and one-third of the world's cargo is now airlifted.

In addition to labour challenges, Liu said civil aviation must also brace for more airport congestion.

“For example, no fewer than 24 international airports across Africa today will be saturated and unable to handle more traffic in just two years' time,” Liu said.