Battery life is the limit on every free-flying drone. A tethered drone gets around it by taking its power from the ground through a cable, so it can hold an observation position for far longer than a battery allows.
How a tethered drone works
A tethered system has three parts: the drone, a ground unit that supplies power, and a cable that connects them. The cable carries power up to the aircraft and, in most systems, a wired data link back down. A winch on the ground unit pays the cable out and reels it in as the drone climbs and lands.
What a tether gives you
- Long-duration hover: with continuous power from the ground, flight time is no longer set by the battery.
- A link that is hard to jam: video and control travel through the cable, not over the air, so they are unaffected by RF jamming.
- A fixed, elevated viewpoint: like a mast that can be raised in minutes, wherever the vehicle or ground unit can go.
- Simple operation: the drone holds a fixed position above the ground unit, so there is little to fly.
Where tethered drones are used
- Perimeter security for camps, bases and critical sites
- Border posts and checkpoints that need a constant watch
- Large public events and crowd monitoring
- Disaster response, as a temporary high viewpoint or communications relay
The limits to plan for
A tethered drone cannot patrol. It stays within the length of its cable above the ground unit, so it is an overwatch tool, not a search tool. It also needs a ground unit and power source on site, and the cable adds weight and is affected by wind. For searching a wide area, a free-flying drone, or a VTOL fixed-wing UAV for long distances, is the better choice.
| Tethered drone | Free-flying drone | |
|---|---|---|
| Time in the air | Long, powered from the ground | Limited by battery |
| Coverage | One fixed position | Can move, patrol and search |
| Data link | Wired, resistant to RF jamming | Wireless |
| Best for | Persistent overwatch | Search, patrol, mapping |
Many operations use both: a tethered drone watching a fixed site while free-flying drones respond to what it sees. Read more about our tethered drone capability, or browse our drone platforms.
