This week the US Patent and Trademark Office approved an application from Boeing’s James J. Childress and John J. Viniotis for an autonomous drone that can be recharged without landing.

Today the amount of time a drone can spend in the air is limited by the amount of fuel or electricity the unmanned aircraft can carry.

But those limitations could soon be a thing of the past.

According to the patent, the system involves battery-powered dirigibles or drones that can deploy a retractable tether. The tether will be able to connect to a power source as the craft hovers. When fully charged, the drone will automatically fly off to complete its programmed task while another drone will fly in and take its place at the charging point.

Depending on the specific application of the drone, the tether can be connected to a variety of sources including land- and ocean-based power supplies. The tether can even be connected to moving vehicles, allowing the drone to charge while flying.

The patent – filed in March 2013 and approved this week – is a reasonable concept for an efficient and effective way to manage and charge a fleet of drones. Because the drones can fly indefinitely without landing, the system forgoes the need for landing and storage space. Of course, the drones would probably have to periodically land for maintenance.

Thus far, the proposed system exists on the drawing board. There’s no word whether Boeing plans to actually build these drones.

Check out a full video overview here