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 Image copyright USPTO Image caption The patent envisages fleets of airships forming the air-borne delivery network 
 
 Amazon has filed a patent for massive flying warehouses equipped with fleets of drones that deliver goods to key locations. 
 
 Carried by an airship, the warehouses would visit places Amazon expects demand for certain goods to boom. 
 
 It says one use could be near sporting events or festivals where they would sell food or souvenirs to spectators. 
 
 The patent also envisages a series of support vehicles that would be used to restock the flying structures. 
 
 Amazon air force 
 
 The filing significantly expands on Amazon's plans to use drones to make deliveries. Earlier this month it made the first commercial delivery using a drone via a test scheme running in Cambridge. 
 
 In the documents detailing the scheme, Amazon said the combination of drones and flying warehouses, or "airborne fulfilment centres", would deliver goods much more quickly than those stationed at its ground-based warehouses. 
 
 Also, it said, the drones descending from the AFCs - which would cruise and hover at altitudes up to 45,000ft (14,000m) - would use almost no power as they glided down to make deliveries. 
 
 Many firms working on drones are struggling with ways to extend their relatively short range, which is typically dependent on the size of the battery they carry. 
 
 The patent lays out a comprehensive scheme for running a fleet of AFCs and drones. It suggests smaller airships could act as shuttles taking drones, supplies and even workers to and from the larger AFCs. 
 
 Amazon has not responded to a request for comment about the patent. 
 
 It is not clear whether the filing is a plan for a project that will be realised or just a proof-of-concept. Many firms regularly file patents that never end up becoming real world products or services. 
 
 Amazon's patent was filed in late 2014 but has only now come to light thanks to analyst Zoe Leavitt from CB Insights who unearthed the documents. 

 CLOSE But Amazon has a few obstacles to get around before making it a reality. Video provided by Newsy Newslook 
 
 Your old Amazon boxes can be repurposed to send donations to Goodwill, and Amazon will pay for the shipping. (Photo: Kevork Djansezian, Getty Images) 
 
 And you thought getting packages by unmanned drone was cool. 
 
 An Amazon patent available through the U.S. Patent and Trademark Office details plans to create an "airborne fulfillment center." Basically, a flying warehouse. Details on the April patent were first uncovered by CB Insights tech analyst Zoe Leavitt. 
 
 I just unearthed the Death Star of #ecommerce via @cbinsights... AMZN patent for airborne warehouses at 45K ft spitting out delivery drones pic.twitter.com/qEz2ilUtJP — Zoe Leavitt (@zoe_leavitt) December 28, 2016 
 
 The patent says the warehouse could remain at a high altitude, and drones "with ordered items may be deployed from the AFC to deliver ordered items to user designated delivery locations." 
 
 The patent also says shuttles could deliver more inventory to the warehouse, as well as transport employees. 
 
 Images accompanying the patent feature a blimp as the chosen airship for the fulfillment center, although it's not clear the vehicle will be part of Amazon's final design. 
 
 Amazon envisions using this concept beyond delivering customer orders. An example used in the patent details how the flying warehouse could be deployed during an event like a football game. The warehouse could stock specific items such as sporting apparel or food, then relocate near the event so customers could order items and have them quickly delivered by drone. 
 
 The patent also says in some cases, the fulfillment center could "navigate to a lower altitude and provide advertising." 
 
 The details of the patent cap what has been a wild month for Amazon, which delivered its first package by drone earlier this month. The test was completed in the United Kingdom, and kicks off a pilot testing period for drone delivery. Amazon still awaits approval from the Federal Aviation Administration to start delivering packages in the U.S. by drone. 
 
 When it's not working on delivery technology, Amazon is opening grocery stores without checkout lines. The company is testing out the concept in Seattle. Users tap their smartphones as they enter the store to log in, and users add items through an app. When the customer walks out, the app charges their Amazon account. 
 
 Follow Brett Molina on Twitter: @brettmolina23. 
 
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– Amazon has received a patent for what one tech analyst calls the "Death Star of e-commerce": a floating warehouse hovering more than 8 miles above the ground and "spitting out delivery drones." The "airborne fulfillment center" could station itself above an event, such as a sports game, so attendees could order food, souvenirs, etc. and have them delivered quickly, USA Today reports. Meanwhile, shuttles could deliver goods and employees to the flying warehouse. The goal of the airborne fulfillment center—held aloft by "helium or hot air"—is to reduce the time and energy it takes to make deliveries, Gizmodo reports. The patent claims delivery drones would save energy by using gravity to take them to their destinations. But Amazon hasn't even gotten FAA approval for delivery drones, let alone a massive floating warehouse. Gizmodo calls the idea "utterly ludicrous" and says it "looks like a total disaster." Meanwhile, the BBC notes that many patents filed by companies never actually become a reality. (An Apple phone patent has a throwback feel to it.)