Estes Firefly Parasite Glider
 

Added this one to my fleet recently.

See the full story at my blog link below.

I had one of those way back when, too. I still have the wing somewhere. . . .

The problem was the stick that made the fuselage would not stand up to even the most (relatively) benign desert landing which ALWAYS involves rocks of various sizes. I considered making one out of carbon fiber, but I got side-tracked with many other things.

I need to do a glider for my NARTrek. Hmmm . . . .

+1 to what MarkB said above.
Fuselage "stick" WAYYYYYYYY too fragile in stock form.
Replaced mine years ago with Carbon Fiber as well.
After it broke twice, it got replaced with the good stuff.
Either it needs to be much larger, or replaced.
One could wrap it with light fibreglass cloth/epoxy during assembly as well, but carbon fiber is the right, light, way to go.

Reinforce with thin CA.

Worked nicely. Very strong and light.