The parent company of the Belfast plane manufacturers Bombardier has won a contract to build private jets worth almost £5bn.
Vistajet, a private charter firm, has signed a deal for up to 142 business jets.
In a statement, management in Belfast said the factory played a major role in the business jet sector and the contract will sustain the jobs of its 5,000 workforce and secure the future of the company.
Michael Ryan, Vice President and General Manager of Bombardier Aerospace Belfast said: "We'll be building those starting next year and probably for the next three or four years, if the options come through, we'll probably be building the options as well, for the next three to five years."
The business jets are specially designed and are the largest available in the world.
Mr Ryan said the business aircraft are doing very well in the Middle East, the Far East and the rest of the world.
He said there is an expectation that by the time the components have been built in Belfast and then the aircraft built in Canada, the world economy will start picking up and be running at good pace by the time the jets are put into service.
Bombardier has plants in east Belfast, Newtownabbey and Newtownards, which design and manufacture parts for planes.
The company is one of the biggest private employers in Northern Ireland.