I am trying to fly a HK450 with APM 2.6 with Arducopter.
Today I made progress and the bird was almost ready to go airborne. I tried a hover just above the ground and the heli drifted slowly backwards and to the side. Not much so I thought I could just give very small control inputs to keep in on the same spot. I was flying/hovering in Stabalize mode.
This did work for a couple of seconds. Then the heli suddenly snapped out of the hover and slammed in to a nearby wall. The damage is bend control rods and broken blades
My question is how can the heli suddenly snap out of the hover and move to the right?