Twin Flyer,
I'm the one with the discontinued GP Chipmunk and to answer your question ....Yes, the wings are built up with plywood and balsa and are detachable. The fuselage and cowl are fiberglass. The wooden spar is attached to a fiberglass center section and the wings slide onto it. They are easy to install and remove and make it much easier to transport. However, Ihave a smoke tank installed in the fiberglass center section and must either remove the tank to reach the plastic bolts that hold the wings or just leave everything attached. I'm lazy so, I'll probably leave them as one piece.

Here's a link to a review Ifound on the web. It may help explain better than Ican.
http://www.rcgroups.com/forums/showthread.php?t=309861

RJ