I began with the breakout of the parts from my kit to get a sense of the fit and accuracy of the parts. CAD is just wonderful as is laser cutting - just a world of difference from the days of gluing flat rectangular sheets together and carving an airplane out of it. As I learn more about CAD, I realize the level of accuracy and detail that can be designed and built into a model - something impossible to do without a substantial amount of time, in the days before computers when many of us began modeling.

I took a few snaps atop the 24" wide plans I produced (two sheets: fuse/vertical & wing/stab) and also took some weight readings to estimate the airframe weight prior to glue joints.

Parts Weight
[ul][*] Fuse & Vertical: 7.7 oz [*] Blocks & Sticks: 5.3 oz[*] Canopy, Wing and Stab Tips: 4.6 oz[*] Wing & Stab Ribs: 0.8 oz
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This results in 18.4 oz but is incomplete because the kit does not contain the totality of the wood required. Wing LE and center sheeting as well as stab sheeting is not included. Triangle stock is also not included as are some other details such as servo boxes, control surface TE hardwood and the wing bottom fuse fairing. Estimating this wood to weigh a total of an additional 7 oz., the airframe can be expected to build to about 30 oz max. With a target all up weight of 56 oz (3.5 lbs), that leaves 26 oz for airframe finishing, retracts, engine (motor) and radio gear.

I will be powering my UFO 25 with a ST X25 with a Macs 1020 (3.5 cc) quiet tuned pipe. The weight of the engine, prop, spinner (Tru-Turn), header, pipe and couplers is 14 oz. That will give me a 12 oz window for airframe finish, retracts, tank and control. I also expect the finished airframe to actually build to less than 30 oz since carving, shaping and sanding has not been taken into account in the calculation above. A 26 oz unfinished airframe might be a more likely final weight reversing the situation to 30 oz of allowable weight for finish and gear.

I look forward to Ralph's build of the prototype!

David.