“The FAA’s requirement that unmanned aircraft stay within a human’s unbroken line of sight throughout its operation is a deal-breaker for Prime Air, as is the restriction on carrying external payloads. That Amazon’s scheme is grounded is not news. It was always going to be. But there’s hope yet for drone delivery. Cincinnati-based Amp Holdings is currently developing a drone, called Horsefly, that deploys from a compartment in the roof of an electric delivery truck.”

Source: www.popsci.com

Robohub previously covered HorseFly, last June: http://robohub.org/horsefly-unmanned-aerial-parcel-delivery-system-uses-truck-as-base/