Thai AirAsia (TAA) will introduce the stretched-fuselage variant of its Airbus A320 workhorse to its fleet to deal with airport slot constraints.
Thailand's largest low-cost carrier (LCC) will begin to phase in more than 10 A321neos in 2019, said TAA chief executive Tassapon Bijleveld.
The A321neo can accommodate up to 240 passengers, compared with 180 seats in an A320, which constitutes the bulk of the aircraft in the fleets of TAA and other AirAsia subsidiary airlines.
"We can deploy these A321neos in busy airports that have no slots, such as Don Mueang, Chiang Mai, Phuket and Hong Kong," Mr Tassapon said.
These higher-capacity jets will supplement the A320 fleet, whose numbers will be raised by seven in 2018 from 56 this year.
More airports in Southeast Asia, which AirAsia's airlines ply, are running out of airport slots and deploying larger-capacity aircraft to maximise available slots.
The A321neo jetliners that TAA will receive are part of 100 aircraft ordered by parent AirAsia Bhd from Airbus at the Farnborough Airshow in July 2016.
With a combined catalogue price of US$12.6 billion (413 billion baht), this new order raised the total number of orders AirAsia had placed for the Airbus A320 family to 575, reaffirming the carrier's position as the largest airline customer for the Airbus single-aisle product line.
AirAsia group chief executive Tony Fernandes has said the A321neo will be operated on the airlines' most popular routes and especially at airports with infrastructure constraints.
Several AirAsia subsidiary airlines facing airport slot constraints at their home bases, including one in India, are likely to see the introduction of the A321neo.
Passenger traffic at Thailand's six major airports is mostly stretched well beyond capacity, by an average of one-third, compounding heavy congestion, according to the latest data.
These airports, including gateway Suvarnabhumi and LCC hub Don Mueang, processed 129 million passengers in the fiscal year to Sept 30, some 32.7 million, or 33.9%, beyond their aggregate design capacity of 96.5 million a year.
Total passenger traffic passing through airports operated by Airports of Thailand Plc in the fiscal year soared 7.7% from the previous year, AoT reported.
The fiscal year also saw these airports handle 823,574 aircraft movements, referring to take-offs and landings, which were up 6% from the year before.
Facing even more critical overcrowding than in the past several years were Suvarnabhumi, Don Mueang and Phuket.
A total of 59.1 million passengers were crammed into Suvarnabhumi in the fiscal year, up 6.5% from 2016, while the airport's capacity stands at 45 million passengers a year.
Don Mueang, TAA's main hub, processed 37.2 million passengers, 7.2% more than the previous year, versus a capacity of 30 million passengers a year.
Phuket handled 16.2 million passengers, up 10.3% on the previous year's figure, though its design capacity is merely 8 million passengers a year.
Chiang Mai recorded 9.97 million passengers, up 8.3% from the previous year, surpassing its annual capacity of 8 million.