ring gear, you didn't read my post. I never said don't balance, just that track affects balance.
Your link seems to take me to a place that wants my money for a "revolutionary tool in rotor track and balance". Are you in sales?????
Every machine is different and different RTB tools ahve different methods of achieving a good result. RADS works well in a 212, but only reasonably good on a 412 (well, when I was working on them anyway. Hopefully RADS is better on a 412 now!).
HUMS on the AW139 works great and I don't agree with your comment about OEM's and master blades.
Many times I've replaced a main rotor blade on a 139 and have had to do NO adjustments. Vertical and Lateral have remained below 0.06 IPS (normal for a 139), which is well below the 0.2 IPS limit. Yes that is correct. I have replaced main rotor blades on the 139 and have not had to do any adjustments.
Try that on a 412!
I'm going to put that down to their blade people being very good at making their blades nearly identical.
Steve, as far as the 412 and RADS goes, when I was working on it, you needed a phase angle corrector in case your adjustments went off on a tangent.
You also needed to keep an eye on what IPS reduction you got for a certain move, compared to what RADS said you would get. Different aircraft had a different sensitivity.
From memory (foggy memory!) we used a 1:1 ratio for mass on the main rotor for what RADS was saying. For the tail rotor we would put 1/2 the mass as the tail rotor seemed to be more sensitive than what RADS thought. For the main rotor driveshaft we did 2/3 the mass. Adjust clock angles as needed.
Some 412's would be good after a few runs. Some would take a week.
I know of one 412 in Alaska (very experienced crew) that had the main rotor blades replaced and the replacement blades were all vastly different hours. Everything reset to nominal and they still had trouble getting good results on the ground (best to get the 412 as good as possible on the ground before flying). 3 weeks later they were still working at it. Bell rep came up to Alaska for a week to show them how to do it and left without improving things.
They finally got it acceptable in most regimes, but not all.
Some people may say that all blades can be made to fly with any other blade, but that just isn't necessarily true. Some people just make crap blades to begin with!!!
Good luck
