12/10/2014 05:51 EST | Updated 02/09/2015 05:59 EST

F-35 purchase cost could rise by $1B to replace lost aircraft

A new report released by the Department of National Defence says that if the Canadian government goes ahead with the purchase of the controversial F-35 fighter jet, it could have to pay an additional $1 billion to replace lost aircraft over the life of the fleet.

The findings are contained in the department's third annual update on the potential cost to replace the CF-18 fleet with F-35 aircraft.

"It is estimated that seven to 11 aircraft could be lost over the useful life of the fleet and the cost to replace these lost aircraft could be in the order of $1 billion," the report says.

The report assumes the delivery of the first aircraft would come in 2020 taking into account the life extension of the CF-18 fleet to 2025.

The report estimates that Canada would pay $45.8 billion for the life-cycle cost cost of 65 F-35s, an increase of $141 million from the 2013 estimate.