The only ones I know of are more like a circle with little V shapes cut in it. Inside the V and the very bottom is a sharp place so that all you can cut is thread. My suggestion would be to leave your real scissors in your checked luggage and take a little bit of quilt as you go or embroidery on the plane. I've been told crochet and knitting are not allowed either.
MaryMaxim and Herrshners both sell the little cutter.