Of these, another Airbus will be delivered to THAI this year, five other Airbus aircraft and the two Boeings will be delivered next year and the other five Airbus planes will be delivered in 2018.
Meanwhile, THAI president Charamporn Jotikasthira said the new aircraft will also be used on existing routes which are facing a surge in passenger numbers as a means to increase flight frequency.
Mr Charamporn said Wichian Buri will fly a round-trip route, Bangkok-Melbourne, Australia, on Sept 16. Flight tests will also be conducted on the aircraft on a domestic round-trip flight, Bangkok-Chiang Mai, between Sunday and Sept 15.
THAI currently operates 23 Airbus aircraft on various routes and the airline has sold one Airbus A340 with 13 other planes waiting to be sold, Mr Charamporn added.
In the second quarter of this year, the airline had reported a 0.2% drop in average cabin factor — a measurement of capacity utilisation — to 69% compared to the same period last year.
Second-quarter losses were lower this year due to a 3.18-billion-baht, or 21.3%, reduction in fuel expenses, he said.
As part of its expansion plans, THAI aims to bolster sales through its alliances which offer flights to destinations where the national carrier does not operate.
Negotiations are under way with 10 airlines flying to Europe to increase ticket sales to that market, he added.