GENEVA (AP) — The Swiss executive branch on Wednesday announced plans to purchase three dozen advanced F-35 fighter jets from U.S. manufacturer Lockheed Martin, which beat three rivals to land a contract worth over 5 billion Swiss francs ($5.5 billion).

The Federal Council recommended that parliament buy 36 F-35A fighters, which came in at a cost of 5.1 billion francs when bids were presented in February. That was “well under” a cap of 6 billion francs approved by Swiss voters in a referendum last fall, a government statement said.

Over the three-decade span of the contract, including both procurement and operating costs, the F-35A would cost 15.5 billion Swiss francs ($16.75 billion), it said.

Other contenders were Boeing’s F/A-18 Super Hornet, France’s Rafale -- produced by Dassault Aviation -- and the Eurofighter from an Airbus-led consortium.

The purchases are part of a multi-year fleet refurbishment by the Swiss air force known as “Air2030” because the division’s current equipment — mainly F/A-18s — will reach the end of its service life by 2030, the government said.

The decision was made after a “comprehensive technical evaluation” based on a cost-benefit analysis, the department said, adding the total F-35A costs including procurement and operating costs came in 2 billion francs less than the second-lowest bidder.

The council also opted to purchase five Patriot ground-based air-defense system units from U.S. contractor Raytheon, which would cost nearly 2 billion — and up to 3.6 billion including operating costs over 30 years.