I just made a short video to demonstrate the problem I was having with static discharge on one of my ZYX fbl gyro units running on a HK 450 Pro with belt tail.metal boom. First part of video shows without a grounding wire- the tail servo & cyclic servo's are twitching as I run it up,& when I touch the ZYX unit plastic case top-the swash goes left & back by itself.
Second sequence shows a thin (temporary for now) copper grounding wire going from tail box,wrapped around boom support brackets,& going to the front frame boom metal brackets. The unit is very stable as throttle is increased,& holds position on all servo's.Touching the ZYX case or frame has no effect. However,when I remove the grounding wire,the unit once again becomes unstable,& touching the case again makes the cyclic servo's go full left & back.
I will make a more perminent grounding wire setup later,but just wanted to demonstrate the glitching I was having. Weather is very dry currently,maybe 20% humidity,& probably is contributing to the static effects.
Last portion of video shows heli flying about a month ago,same exact setup (no grounding wire at the time) & was steady as a rock & very stable. The tail twitch only showed up recently last week during a session. Hopefully,adding the grounding wire will solve any future problems with static discharge affecting the gyro.