Video of bug here: https://www.youtube.com/watch?v=vgGSiei0QoU
May 10 2016
Duplicate ticket for this issue here: http://feedback.arma3.com/view.php?id=22504
This has been a problem since the Alpha and really needs to be fixed.
Can confirm this issue no longer exists in version 1.48.131561.
This issue is still present in version 1.54 Stable.
I believe this has something to do with the aiming dead-zone.
I use pedals for helicopter control and setting the dead-zone to zero on the pedals fixed this issue.
Finding it hard to believe that no one else has noticed this...
This an ugly kludge designed to work around clipping issues; short-sightedness (again) on behalf of the devs.
For me, desync kicks in after the 3rd player joins the server. Everyone who joins after player #3 gets 100000 desync.