Online retail giant Amazon is thinking of building mobile maintenance facilities for drones - on trains, boats, and in other vehicles where drones could be fixed without worrying about taking them into the shop, according to a new patent published by the United States Patent and Trademark Office and spotted by Business Insider.

Though the concept seems a bit far-fetched, its commercial applicability isn't that complicated. Amazon is investing heavily and wants to deploy them for delivery purposes. But, in order to make that happen sooner, the company would need a way to keep its unmanned aerial vehicles (UAVs) charged and flying all day long.

This is where the concept detailed in the patent, published on 2 August, could fit in. Amazon could use the special maintenance facilities to deploy drones to move products to areas of anticipated demand, considering the history of purchases or upcoming events in such areas.

"Intermodal vehicles may be loaded with items and an aerial vehicle and directed to travel to areas where demand for the items is known or anticipated. The intermodal vehicles may be coupled to locomotives, container ships, road tractors or other vehicles, and equipped with systems for loading one or more items onto the aerial vehicle, and for launching or retrieving the aerial vehicle while the intermodal vehicles are in motion," read a part of the patent's abstract.

"Additionally, intermodal vehicles may be loaded with replacement parts and/or inspection equipment, and configured to conduct repairs, servicing operations or inspections on aerial vehicles within the intermodal vehicles, while the intermodal vehicles are in motion."

As Amazon's drone delivery programme is still at a nascent stage, there's no telling whether the company plans to bring this patent to life. The company has filed a number of patents over the past few years including one hinting at drone towers, but only a handful of them have seen the light of day.