AeroPoints need a clear view of the sky above 15 degrees for us to guarantee good results. 

The failures that you see are most likely due to other factors such as placing the AeroPoints near obstructions such as trees or buildings, or accidentally moving the AeroPoints.

If you are certain that this has not happened, we can attribute the error to other sources such as atmospheric effect (effect of ionosphere and tropospheric refraction, which may cause the distance to deviate from its true value); satellite geometry at the time of the AeroPoint survey (position dilution of precision); and other external factors  which are out of our control. 

Did this answer your question?