Ok hands up! I managed to break one the other week...!
The combination of an under reading ASI, pesky cross wind and bumpy field, not to mention my sloppy flying technique was too much for the poor corroded tailspring to take... It promply snapped - leaving me very red faced and the new owner (who is a family member) very degected...!
My logbooks simply states 'first flight Kitfox - broke it'
Seriously now, they are quite short coupled and do tend to bounce like crazy if you get it wrong. I discovered that the tail spring has been modifyed twice and now is of a longer, solid Alu bar which makes the ground angle less steep and being firmer, does not bounce like the old leaf spring variety - might be something worth checking out if you are looking at one to buy.
All in all, I quite like them. If it wasn't for the strimmer engine fitted to most of them I'd be tempted to buy one myself...!
Kingy