Speaking of noises...
During a very deep cold snap last month a little squeak developed. It went away when it warmed up so I didn't fix it 2 weeks ago. My mistake. It got cold again, came back, then a chinook wind (warm wind) blew in and it DIDN'T go away but it was way too windy to lower the tower. Had to listen to it for 2 weeks with no chance to fix it. Finally a quiet day came today.
It was hard to tell from the ground what the source of the noise was. Either the tail or the yaw mount could do it. I was also worried that the noise would not be reproducible when the tower is down. Leaning horizontally, the surfaces in contact won't apply pressure. It took a bit of watching from below to catch a moment when the turbine did yaw without making the noise, and the tail did move plus make the noise, to be sure. So it was the tail.
Another lowering process with the new tower. I didn't get into any trouble but I still have to admit there are a lot of "memory" items, like having a ladder to prop up the gin pole a certain amount so that it can start tilting over, and so on. There a lot of steps and some aren't obvious.
I decided I needed a "washer" between the contact surfaces in the tail hinge. Not having a 7/8" ID washer handy (who does) and my lathe is still rigged up with a generator test contraption, I had to get out the hacksaw and just cut a bit of tube off the other end - then insert it between the offending hinge surfaces.
Tower is back up again, just waiting for the wind to come back (give it a couple of days)