In an unusual reversal of roles, Amazon has purchased 11 jets, seven from Delta and four from WestJet to boost its growing delivery network and get orders to shoppers faster. (One wonders if the carriers will be delivered to the online shopping giant’s doorstep in giant cardboard boxes).

Amazon says it’s the first time it has purchased planes for its delivery network, having preferred to lease equipment over the past couple of years to build its fleet.

“Having a mix of both leased and owned aircraft in our growing fleet allows us to better manage our operations,” stated Sarah Rhoads, VP of Amazon Global Air (formerly called Amazon Prime Air).

Seattle-based Amazon has been working to deliver most of its packages itself and rely less on UPS, the US Postal Service and other carriers. Besides its fleet of planes, Amazon has also built several package-sorting hubs at airports, opened warehouses closer to where shoppers live and launched a program that lets contractors start businesses delivering packages in vans stamped with the Amazon logo.

Amazon said the planes, all of which are Boeing 767-300s, will be converted to hold cargo instead of passengers. The jets that it is buying from WestJet will join Amazon’s fleet this year, and the rest from Delta will be ready by next year. The purchases will bring its total fleet to 85 planes by 2022.

The company declined to say how much it is paying for the planes.