Amazon files patent for flying warehouse Published duration 29 December 2016

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