In the age of instant gratification, retail giants are turning to technology to fill customers’ orders as quickly as possible. The once-unimaginably-fast two-day shipping standard is starting to seem outdated and sluggish. We’ve previously written about Amazon’s experimentation with drones and floating warehouses in its pursuit of near-instantaneous delivery. Now, retail giant Walmart is looking to the sky, too.

In August 2017, Walmart filed a U.S. patent application for blimp-style machines that would serve as launching bays for delivery drones, quickly fulfilling orders and sending products directly to shoppers’ homes. The floating distribution centers would fly as high as 1,000 feet and could be operated autonomously or by a remote human pilot. The movable warehouses could also serve a wider area than traditional stationary warehouses that can only fill orders within driving distance.

If Walmart’s patent application sounds familiar, that’s because in April 2016, Amazon was awarded its own patent for a similar concept, termed airborne fulfillment centers (AFCs). Walmart’s patent application, however, offers more detail about how it would power the airborne warehouses.

Both patents seek to lower costs associated with “last-mile delivery”—that is, from distribution center to final destination. Walmart’s patent application explains that the floating warehouses will cut out the step of sending products to a delivery location, saving time and money. The company would also be able to avoid traffic congestion in major cities and long driving distances in rural areas by incorporating drone delivery.

As with Amazon’s drone delivery and AFC concept, Walmart will likely face substantial regulatory hurdles, including aviation authority approval. As more retailers seek to be airborne, regulatory agencies and legislators may refine current restrictions.