Amazon is bolstering its proprietary air shipping capabilities in the wake of announcing plans to cut its standard Prime shipping time from two days to one day during its April 25 earnings call. The company also recently started making free one-day delivery available to Prime members with no minimum purchase amount on more than 10 million products. "These new aircraft create additional capacity for Amazon Air, building on the investment in our Prime free one-day program," said Dave Clark, senior VP of worldwide operations at Amazon. "By 2021, Amazon Air will have a portfolio of 70 aircraft flying in our dedicated air network."