ImRich
06-25-2004, 11:29 AM
I have finally solved my pitchyness with my white MinAir 20g paddles on my R50V2 (this may also affect R30V2's too as I believe the mechanics are the same in this area).
The problem was not the paddles at all, although because they are more 'powerful' they tend to show the issue more than the stock paddles do.
The root issue was that I had the length of the 'elevator idler rod' a bit too short. The manual calls for it to be 66mm, ball center to ball center. I think it should be closer to 67mm ball center to ball center.
By the 'elevator idler rod' I mean the rod which goes between the elevator arm (pitch arm) and the elevator idler arm (which is the arm at the collective tray pivot point, between your elevator servo and the elevator arm).
I carefully measured the distance between the bearing of the idler arm pivot point and the center of the pitch arm pivot point and came closer to 67mm on my R50V2. The manual calls for the rod to be 66mm here. By using 66mm (or anything shorter), the geometry is not correct and you will induce tiny pitch changes to the swash plate at full positive and negative collective. This is what causes the pitchyness when doing fast forward flight!
If this rod is too long, you may get a similar but opposite affect that I did. My R50V2 pitched down with full collective fast forward flight.
By making the elevator idler pushrod dimension 67mm from ball center to ball center, all of my pitchyness in fast forward flight has gone away and my R50V2 is much nicer to fly now!
FYI, the stock paddles show this problem also, but since they make the heli more stable, they are simply much slower to react to the problem, so many pilots may have this geometry problem and not even know it. Unless they were 'smarter' in setting up their mechanics than I was! :D
The white MinAir 20G paddles are much more aggressive and and show this issue quickly!
So shame on me for not checking this dimension earlier! The difference between 66mm and 67mm is not really noticable by eye in the geometry of the mechanics (or at least me eye :glasses2: ). However the difference in flight responce is dramatic IMHO.
I found this problem when a friend loaned me his paddle pitch guages which happen to have bubble levels on them. I noticed that my paddles where changing elevator pitch (for/aft cyclic) ever so slightly when I changed my collective from starting at zero pitch (centered) and going to full positive or full negative collective.
Check your geometry on this rod to ensure that your R50V2 (and probably the R30V2 also) to be sure that you're not missing out on some better rappy flight performance.
I don't know if this dimension is the same on the V1 machines as I don't have one to check right now.
The problem was not the paddles at all, although because they are more 'powerful' they tend to show the issue more than the stock paddles do.
The root issue was that I had the length of the 'elevator idler rod' a bit too short. The manual calls for it to be 66mm, ball center to ball center. I think it should be closer to 67mm ball center to ball center.
By the 'elevator idler rod' I mean the rod which goes between the elevator arm (pitch arm) and the elevator idler arm (which is the arm at the collective tray pivot point, between your elevator servo and the elevator arm).
I carefully measured the distance between the bearing of the idler arm pivot point and the center of the pitch arm pivot point and came closer to 67mm on my R50V2. The manual calls for the rod to be 66mm here. By using 66mm (or anything shorter), the geometry is not correct and you will induce tiny pitch changes to the swash plate at full positive and negative collective. This is what causes the pitchyness when doing fast forward flight!
If this rod is too long, you may get a similar but opposite affect that I did. My R50V2 pitched down with full collective fast forward flight.
By making the elevator idler pushrod dimension 67mm from ball center to ball center, all of my pitchyness in fast forward flight has gone away and my R50V2 is much nicer to fly now!
FYI, the stock paddles show this problem also, but since they make the heli more stable, they are simply much slower to react to the problem, so many pilots may have this geometry problem and not even know it. Unless they were 'smarter' in setting up their mechanics than I was! :D
The white MinAir 20G paddles are much more aggressive and and show this issue quickly!
So shame on me for not checking this dimension earlier! The difference between 66mm and 67mm is not really noticable by eye in the geometry of the mechanics (or at least me eye :glasses2: ). However the difference in flight responce is dramatic IMHO.
I found this problem when a friend loaned me his paddle pitch guages which happen to have bubble levels on them. I noticed that my paddles where changing elevator pitch (for/aft cyclic) ever so slightly when I changed my collective from starting at zero pitch (centered) and going to full positive or full negative collective.
Check your geometry on this rod to ensure that your R50V2 (and probably the R30V2 also) to be sure that you're not missing out on some better rappy flight performance.
I don't know if this dimension is the same on the V1 machines as I don't have one to check right now.