The patent application was filed two years ago but was spotted only on Wednesday by Zoe Leavitt, an analyst at technology data and research firm CB Insights.
According to the patent filing, drones launched from the so-called “airborne fulfillment centers” (AFCs) would use far less power than those launched from the ground.
The AFCs would hover at about 45,000 feet (13,700 meters) and be restocked and resupplied by “shuttles or smaller airships.”
Amazon, which was not immediately available for comment, has laid out plans to start using drones for deliveries next year.
Amazon Prime Air has begun private trials in England, and the first customer delivery by drone recently took place.