Travellers should get used to long waits and delayed flights as more and more planes clog air traffic routes, according to an official with the U.S. Federal Aviation Administration.

'"Delays are mounting due to congested airspace and congested airports."—Marion Blakey, Federal Aviation Administration

The agency on Thursday estimated there will be an average of 1.4 million more planes departing and landing every year until 2020.

"Delays are mounting due to congested airspace and congested airports," said FAA administrator Marion Blakey. "The congestion is really becoming a chronic thing."

According to Blakey, U.S. airports in 2006 had a poor performance record, with more than 490,000 flights delayed. Last year, U.S. air traffic controllers coordinated 61.1 million takeoffs and landings.

Blakey said the current air traffic control system was showing its age and must be modernized to include satellite-based navigation, in order to avoid potential gridlock.

9 billion passengers annually by 2025

In January, the industry body Airports Council International estimated that by the year 2025, more than nine billion people will move through airports around the globe annually - more than double the number of passengers in 2005.

Airports Council International estimates that by the year 2025, more than nine billion people will move through airports around the globe annually.
(CBC)

Robert J. Aaronson, director general of the Airports Council International, said that current travel patterns indicate there will be a shift toward using larger aircraft.

Canada's largest airport, Toronto's Pearson International Airport, ranked 29th in 2005 air travel, handling 29,914,750 passengers, according to the ACI.

Atlanta topped the list with 85,907,423. Chicago, London, Tokyo and Los Angeles rounded out the top five.

With files from the Associated Press