Drone technology has made huge advancements and had major success in recent years. With this success comes an increased focus on the security and safety of drones, drone users and those living in areas with drone activity.

Reflecting this, Governments around the world are currently developing and putting into place regulations to improve the safety of drones.



In the UK the “Drone Code” ( ) has 3 key points:

  • Keep the drone within site at all times and don’t fly higher than 400 feet
  • Keep your drone away from aircraft, helicopters, airports and airfields
  • Use your common sense and fly safely.

The onus of adhering to the Drone Code and any other regulations lies with the drone operator.

Technologies such as GNSS Geo-fencing have been put forward as solutions to ensuring drones are prevented from flying over restricted areas.

But how do you ensure a drone remains within line of sight and within a limited range and what happens when it does go out of line of sight or exceeds the allowed range?

PACTEC’s UAVALERT uses Radio Frequency Ranging technology to ensure that a drone remains within a specified range of the operator and more importantly stays within line of sight of the operator.

UAVALERT operates on a Line of Sight basis. Where a drone and its associated remote control are equipped with UAVALERT modules the drone can be notified when it is no longer in sight of the operator.

The UAVALERT module will notify the main control unit of the drone when it detects that it is out of sight the operator.

The drone can then be programmed by the manufacturer to respond to this notification by either hovering in its current position, return to ground level or potentially returning to its point of origin.

The Ranging feature of RF Technology allows the drone to calculate how far it is from the operator.

The RF module is pre-programmed with a limit that it must remain within from the associated remote control. This limit cannot be altered by the user and is set by the manufacturer.

When the RF Module detects that is out of range it notifies the drone’s main control unit. The main control unit can then react to this notification by hovering, landing or returning to its point of origin.

In both cases the power consumption can be kept to a minimum by having a multi-second interval between communications.