string flying?

I'm having trouble with a few of my planes showing up with strings connected to them! They are as follows: The Cessna C172P Skyhawk, the 182 Skylane, the Aviat Husky, the DHC-3 TTC Super Otter, and the DHC-2 Beaver MK1 (wheels). I didn't know cox was making planes for FS9.
They are all well made and I hate to remove them, but the strings are a terrible distraction.
My question is how to get rid of the strings? ???

