DJI Phantoms and other multirotor UAV (drones) use GPS to calculate their position above the Earth. It’s what makes them so easy to fly and the DJI Phantom GPS programming powers the Failsafe, Home Lock, and Ground Station features, but what are the risks of losing satellite connection? One of the external forces that can reduce the satellite signal strength and cause a string of mishaps that might lead to the dreaded flyaway is a geomagnetic storm and this aspect of space weather is measured using the Kp-index (also known as the K-index).
The Kp-index is often used to determine the chances of seeing the Northern Lights (Aurora Borealis). Without going into the science of it too deeply (just google kp-index if you want to learn more) the index is a scale of 0-9 (the planetary index) which denotes the strength of disturbances in the Earth’s magnetic field. These disturbances are caused by solar flares so increased solar activity is likely to have a knock-on effect on your ability to fly your DJI Phantom in GPS mode.
The lower the figure the better, so when the index is in the green area (0-3 on the scale) there’s a good chance of strong satellite lock. When it goes over 3 and stronger then expect disruption to your satellite connectivity. Anything above 5 indicates a magnetic storm of increasing strength. Check here at any time as this page is updated automatically and you can download an app (iOS, Android) for checking when mobile.
Note: The bars in the image below are in 8 x 3 hour segments.