I have tried several methods to replicate the antena wire on aircraft and they all end up broken or knocked off. I use shearing elastic (in the UK) a very thin elastic that, I think is for knitting into the cuffs of jumpers and the like to elasticate them. Use super glue to attach it. It's quite strong, you can actually pick up small models with it attached (1/48 Bf 109) and because it is flexible it gives, without breaking when knocked. It can be coloured with felt pens.
Mal
PS I hope to be posting some pictures, with antena wires, on Armorama soon. I'll try and remember to let you know when.