RE: Large scale ultralights
OK some more details on this bird. I iriginally had a spair Honda 22cc 4 stroke engine not doing anything and thought a ultalight wood be good for it but the engine had no where near enough power when i did taxi tests on the fraim so i bought a new engine for it.
The plane is 1/3 scale of a real ultra light called an (air bike) there is quit a bit of info on the internet for this plane and there is a couple of small basic outline drawings of it and the wingspan for the 1 seat version is 26' so that would make my 1/3 scale wingspan at 104" and i just used the small drawing to measure up the other parts. there is a tandom version as well. There is also some info here on rcuniverse about this plane with scetches that i used. My wingspan is now 110" with the winglets added. The pilot figure is 1/3 scale.
cord 18", and i used Clark y for airfoil, it has flaps, costom suspension, the engine is a DZY twin cylinder 48cc 4.2hp engine looks good and it will have plenty of power with this engine. The airfraim is all STEEL and i used car brake line tubing which they some times call bundy tubing, it is lite wall with a copper coating on it and very easy to work with and not to heavy, I used 3/8" die for main runners and 1/4" for all diagonals and other bites, and used 68% silver solder and oxy asetaline to weld joints, this stuff melts as easy as normal solder at low temp but is much stronger, but more exspensive, just file ends of tube to get good fit so you start with not much gaps. using steel looks fantastic the joins are so neat and it is so easy to add strong brackets for anything such as wing stuts.