Tokyo -Japan Airlines (JAL) on Thursday said it would order up to 59 regional jets from a unit of Mitsubishi Heavy Industries and Brazilian plane maker Embraer, as it looks to retire some of its gas-guzzling domestic fleet.
The former flag carrier announced plans to buy up to 32 of the country's first domestically produced jet airplane, while it would order as many as 27 jets from Embraer.
The airline did not release financial details, but Mitsubishi Regional Jet (MRJ) earlier said the 32-plane order would total about $1.5bn at list prices. Airlines usually get a discount from such prices on large purchases.
JAL said it expected to take delivery of the Mitsubishi aircraft in 2021, while the Embraer 170 and 190 aircraft would start being delivered in 2015.
The Japanese airline's key domestic rival All Nippon Airways has already ordered 25 MRJ planes, becoming the first customer to buy the aircraft.
Mitsubishi Aircraft was founded in 2008 as a plane manufacturer and plans to release its first model in 2017.
The state-backed Mitsubishi jet project will compete with small aircraft produced by Embraer, Canada's Bombardier, as well as jets designed by Russian and Chinese firms.
It will be the first commercial passenger aircraft in four decades and the first jet to be developed in Japan.
Japan has in the past developed a turboprop plane, the YS-11, which was the only one built domestically since World War II.
It made its debut flight in 1962 and production ended in 1974.
The Mitsubishi plane would have 70 to 90 seats and be equipped with the new energy-saving "geared turbofan" engine designed by US-based Pratt & Whitney.
Including the order announced on Thursday, Mitsubishi has secured orders for more than 400 of its regional jets, the minimum required to make the project profitable, the Nikkei business daily said.