Unmanned aerial vehicles play a very important role in different technical problems. They can take photographs of the area, track forest fires, control offenses and be useful in another fields. Nowadays tethered high-altitude platforms have a particular interest. They have a number of advantages over autonomous devices. For example, they can work for a sufficiently long time and do not depend on the limited resources of batteries. This allows them to be used as transmitters for mobile phones and for other purposes where it is impossible to use autonomous unmanned platforms. In addition, they can carry a much higher load and have a higher power. However, there are some problems connected with navigation of the platform. The wind can change the location of the platform, which should be corrected. The coordinates of unmanned aerial vehicles are usually found using GPS or GLONASS systems. Unfortunately, the signal can be quite weak in some areas, so it is necessary to take the reserve navigation system, which will be connected with beacons located on the ground. In this work we present the idea of system of navigation of the tethered platform, which takes into account its main features and can give us the opportunity to stabilize the location of the vehicle. We give the main formulaes for the coordinates and estimate typical mistakes while measuring them.