A Prime Air cargo plane, operated by Amazon.com Inc., sits on display with other passenger jets during the 53rd International Paris Air Show at Le Bourget, in Paris, France.

Jason Alden | Bloomberg | Getty Images

Amazon is turning to an unlikely partner to help expand its package-delivery business: a low-cost airline.

Sun Country Airlines, a small, Minneapolis-based leisure carrier, will start flying a fleet of 10 converted Boeing 737-800 freighters in the second quarter of 2020, part of a plan Amazon announced earlier this year to expand Amazon Air with the leased single-aisle planes, the airline said late Tuesday.

Amazon has been growing its Amazon Air unit, which currently counts on cargo airlines Atlas Air and ATSG to fly its packages. Amazon owns warrants to buy minority stakes in both companies and has been bringing more logistics operations in-house. In June, said it would no longer provide express shipping for Amazon.

Sun Country, which is owned by private equity firm Apollo Global Management, will use the business to help level out the seasonality of leisure flying, which surges in the first quarter when vacationers head south, CEO Jude Bricker told CNBC.

Those seasonal fluctuations are among “the core challenges we have with growing our business,” said Bricker, adding that Amazon’s demand peaks in the fourth quarter, before the airline’s period of peak demand.

The deal came together last week, but Bricker said he first approached Amazon to try to sell the company a used plane, which didn’t pan out. Then Amazon earlier this year came back to Sun Country about a cargo deal.

Cargo flying “wasn’t part of our plan,” Bricker said.

Sun Country will add 150 pilot jobs over the next 18 months, bringing its total to 500, to keep up with the extra flying Amazon will require.

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Correction: Amazon approached Sun Country in mid-2019. An earlier version misstated the year.

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