Usually, airlines and airports say 'no knitting needles' without making the distinction between straights and circs, but considering the fact you could strangle someone with a circular one, I suspect no is no in all cases here. It also depends on the airport or even the security guard, but if you fly with your knitting, do keep in my mind that they could confisquate your needles at all times, so don't leave the blanket on the circ when you're going through security: they might pull the needle out or take the whole project. Better to put a lifeline in.
That said, if the rules aren't clear about wooden circs, you aren't exactly violating those rules. I'm not sure if rosewood will show up when they put your bag through the machine (they scan for metal, don't they?) but they can still search your bag, of course. Better call them and ask, I think. Safe and sorry and all that.
I took my bamboo sock needles with me on the plane to Berlin, wrapped in between pencils and pens in my pencil case, and they didn't find them, but then during the flight I didn't dare to take them out and knit - it was my first flight ever and was too scared to do anything but hoping for it to be over soon.
