Financial Post, Feb 2017;
''The federal government’s $372.5-million loan to Bombardier may not be fully repaid for 15 years, the company said Thursday.
The interest-free loan is “royalty repayable,” Bombardier chief financial officer John Di Bert said, providing details for the first time on the terms of the government aid that was announced earlier this month.
“That means that it will be repaid on either a function of business jet deliveries or CSeries unit deliveries,” Di Bert told analysts on the company’s fourth-quarter earnings call.
“It will be over a significant amount of time,” he added. “The program runs for about 15 years including a bit of a grace period the first two years, so no repayments for the first two years.”

So... no interest, 15 years to repay, no repay for first 2 years.....
 There's no interest, all they repay is the principal. they have 15 years to do it, contingent on sales.  Sounds free to me.