I've seen the Shoestring fly, and yes it does fly very stable - even makes one of our club members look GREAT when landing!

Do different on the PT-19....maybe go for some 'struts' from Robart and use a different number than what they supply - I used only the '4'....other than that - noope.

What engine you thinking of using? Mine had an OS .91 and with the manifold 'extra' the entire muffler is out of site!

Jerry