Amazon obtained US Patent No. 9,305,280 for “airborne fulfillment center (“AFC”) and the use of unmanned aerial vehicles (“UAV”) to deliver items from the AFC to users. For example, the AFC may be an airship that remains at a high altitude (e.g., 45,000 feet) and UAVs with ordered items may be deployed from the AFC to deliver ordered items to user designated delivery locations.” See the patent here:  Amazon Patent