It seems that there are "Compass error" mid-flight happenning more and more. One good question that I read is "Why Spark flies away, why not just hoovering in place?" And there were people explain that because there is no GPS/Compass so maintaining position is not possible, the Spark goes ATTI then goes with the wind.
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But, Spark does equipped with "Vision Positionning" system why not use the system to maintain its position. Though the system works at low altitude but if the loss of GPS happens at that altitude it can use the system. It can also lower its altitude to the maximum height that vps works.
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Is this possible?

It can be a good idea,  but it may hard to be realized from a technical perspective. Anyway, I will forward this idea to our engineers.