AILERON "VIBRATION"
From CP59, Page 9, April, 1989

     The reports in CP58 have really put the cat among the pigeons! A controversial topic, to say the least. In spite of all of this, only three flyers have reported finding their ailerons vibrating visibly in flight (one was not sure), one reported finding his vibrating at various RPM's while running on the ground -probably true of all EZ's while they are sitting on their wheels (the tires are like springs, as is the gear), so we believe you must look for this problem while in flight and it will be difficult to see and will require a rear seat passenger to watch the ailerons. If you have a visibly vibrating aileron or ailerons, you should increase the mass balance as required to a maximum of what it takes to balance the ailerons with the top skin level. If it only takes 25% or 50% of the maximum to stop the vibration, then that is enough. Unless you know you have this problem, do not change the mass balance.
     Brock has the new aileron belhoms available now and many have been delivered and installed. If you have evidence of worn or beaten out rod end bearings in your aileron control system, you should ground your airplane until you have replace the original belhoms with the new part which is about 8 time stiffer and this is out of the vibration frequency that has been causing the problems. A number of Long-EZ owners have reported worn out rod ends, but far more have reported no sign of wear or vibration. Apparently, it depends greatly on the vibration characteristics of each engine/prop/mount combination and it does not necessarily occur in all Longs - watch for it, though, this is a potential accident waiting to happen - always listen to your airplane - it will invariably try to warn you before it bites!