success! Is it within expected performance parameters to get to 3 meters under 1 or 2 seconds? It is a bit difficult to read but it seems it went up there really fast :)
It was a low frame rate initial video, which had the effect of making the helicopter look like it suddenly shot up to the 3 metre point. Apparently proper decent FPS video clips will be downloaded over the next couple of days which should show a smoother (but still quite fast) ascent.
Counting pixels in that image it seems like both the ascend and descend took exactly 5 seconds each. So that's about 2.16 km/h or 1.34 mph.
Or about 60cm ascent or descent per second. For earth based quadcopter type UAS, straight up or down ascent or descent would typically be measured in m/s.