We often refer to “Pegasus” as the eye in the sky, watching over the roads and catching offenders
who are speeding, carrying out dangerous moves, using their mobile or not wearing a seatbelt, for
example, but what exactly is Pegasus?
Often thought to be the helicopters, Pegasus is actually the name of the equipment carried, not the
aircraft itself. Some of the DGT helicopters are not fitted with Pegasus, and are just used for traffic
monitoring.
The helicopter is positioned above the vehicle to maintain visual contact. The pilot and cameraman
operate in co-ordination. It is equipped with two cameras: one, panoramic, follows the vehicle and
captures its speed; the other, with telephoto lens, reads the registration number.
Starting from the position of the helicopter, a GPS calculates the co-ordinates of the vehicle.
A laser rangefinder measures the exact distance between the helicopter and the vehicle.
With the successive positions, the speed is determined. The system measures every 3 seconds and
the average speed is calculated. Speeds between 80 and 360kph can be detected.
The offence is recorded and transmitted telematically.
How Pegasus Works
The aerial radar has an advantage: it's more selective and allows observation of drivers' conduct,
identifying risky behaviours. Pegasus can operate from a height of 300 metres and from a distance of
one kilometre away from its target.
The purpose of the system is to recognise the geographical co-ordinates (latitude and longitude) of
the vehicle it's checking in order to calculate its speed.
Firstly, the helicopter is positioned with extraordinary precision, by way of various mechanisms
(gyroscopes and speedometers) and a computer programme added to the surveillance cameras.
Next, a laser measures the distance between the helicopter and the vehicle every three seconds.
With these data, the successive movements of the vehicle and its speed can be determined to
record the offence. With the offence confirmed, a frame from the video recording is sent as
evidence telematically to the Centre for Automated Complaints Processing (ESTRADA), where the
incident will be handled. This also includes anticipated criminal offences, for which a Guardia civil
patrol can be contacted immediately from the helicopter.
How the new aerial radar works, step by step:
Starting from the position of the helicopter, the co-ordinates of the vehicle are calculated by GPS.
A laser rangefinder measures the exact distance between the helicopter and the vehicle.
The speed is determined from the successive positions. The system measures every three seconds
and calculates the average. Speeds between 80 and 360kph can be detected.
The offence is recorded and handled telematically.