Learn how flying in close proximity to the earth's magnetic poles can affect your compass and how to ensure safe operation.
After firmware V1.12 this issue is no longer as relevant, and the emergency landing logic has been removed. In the case of magnetic interference, the safety landing mode has been removed and replaced by a seamless recovery mechanism. This allows you to proceed with the flight even if the compass measurement errors occur after take-off. The recommended guidelines below are still good to practice but far less significant than previously before V1.12.
Some regions which lie close to the magnetic north or south pole create a challenging environment for the magnetic compass measurement. The reason being that the magnetic field in such regions is close to vertical, drastically limiting the usefulness of a compass measurement.
Which are the most-affected regions?
The most affected regions are the areas with a magnetic inclination above +/- 80 degrees. Specifically, these are the following areas: Far north of Canada, northern Greenland, Northern Russia, Eastern Antarctica.
How does the WingtraOne currently handle these conditions?
- Once flights in these regions are detected, the WingtraOne will automatically switch to a special flight control configuration, which considers these effects during cruise flight. The biggest challenge for the flight controller remains for the period between the take-off and forward cruise transition.
- In the case of bad compass measurements on the ground the WingtraOne will takeoff and then start to move sideways (because it doesn't really know in which direction it should move its elevons to fly straight up). However, within seconds the control system will realize that something is wrong, switch to the recovery mode, and continue the mission as planned.
- Note that if the WingtraOne reaches transition altitude before this happens it will still transition to cruise flight. Since the heading is bad this might still result in the transition being in the wrong direction.
How can you as an operator increase the safety of your flight?
- Always check the heading of the WingtraOne in WiP before takeoff and compare it to the real orientation of the vehicle (Reboot and switch takeoff location if error > 45 degrees).
- Plan the mission such that a transition to cruise in the wrong direction does not lead to critical consequences. (The maximum expected transition direction error is directly proportional to the heading estimate error on the ground)
- Lowering the transition altitude can help reduce the chance of an error, but clearing obstacles is more important