According to multiple reports, Amazon has spoken with air-cargo companies about leasing jets to start its own air delivery operation. The Seattle Times reported that Amazon was interested in 20 Boeing 767 jets to lessen its reliance on third-party carriers like UPS and the United States Postal Service.

The mega e-commerce seller is already running a trial operation out of Wilmington, Ohio, sources said. Five planes that are being operated by subsidiaries of Air Transport Services Group have taken a total of 217 flights from November 1 to December 17. The flights have landed in Wilimington and four other destinations: Dallas; Tampa, Fla.; Ontario, Calif.; and Allentown, Pa – all near Amazon warehouses.

Currently, Amazon uses the United States Postal Service for its Prime delivery service. By rolling out a cargo service, the company would seek to minimize delivery delays caused by holiday volume or other factors. Two years ago, Amazon offered $20 gift cards to customers whose gifts weren’t delivered in time for Christmas due to overwhelming holiday deliveries for UPS and FedEx. According to data from shipping software company ShipMatrix Inc., last week UPS delivered 96.1% of overnight and two-day packages on time. The week before, the figure was 95.4%.

In recent years. Amazon has sought to exercise more control of its delivery. The company has started to use its own couriers for deliveries close to its fulfillment centers, and has explored drone technology to deliver packages straight to customers.