Original Posted By:> Peter Knowles
Peter,I encountered the same problems with my Piet when I built it back in 1970.Some tinkering reduced the simultaneous slackening and tightening of boththe forward and aft elevator cables and I flew it that way for three yearswithno problems except at the extreme limits of elevator travel. Tensionchanges were minimal up to about 25 to 30 degrees of travel either way and anyextra deflection was not required because Pietenpol elevators are POWERFUL, re-quiring little movement to get a reaction.As designed, Pietenpols have no elevator stops. I wanted to limit theelevatortravel with stops because of the variable cable tension problem and thefactthat it is considered good aeronautical practice to incorporate controlstops.Ideally, these should be located at the control surface itself, but thelight construction of Pietenpol elevators precluded this. So I weldedadjustablestops to the torque tube just ahead of, and behind, the rear stick. Withthese, the travel is 32 degrees up and 25 degrees down. There is no lack ofelevatorauthority and the variable tension problem is minimised (but not totallyelimin-ated). I have flown this setup for nearly 600 hours with no problems.I hope this may help you solve your problem.Graham