Ken, Have you looked at Cherry BX-2 removable wing? http://www.spang-air.de/Mai_2005_-_14_gr.jpg http://www.spang-air.de/Mai_2005_-_16_gr.jpg
Here you can see tapered spar which slides into center spar. It is also clearly visible "socket and receptacle" type of connection for aileron control tube. It automatically connects when you plug in the wing into the wing stub. It simple, and easy to take them out or put them back in. Only one bolt per wing. I haven't build them yet. Still working on the tail (horizontal is removable too). Check other photos on the following website http://www.spang-air.de George Westbury, NY >>thanks for the in put but i'll probably enfd up doing some experimental >>work on a test spar i'll let yall know what i come up with -- i'm looking >>to make an attachment that plugs in and then bolts ****although JOACHIN >>did have a good idea with the explosive bolts! >> >> >> >> >> > >