ORIGINAL: dfturnock
I just weighed the eyelash, at present construction time, with all of the parts not on yet, engine, mount, prop, and spinner, and a couple servos, minus fuel tank, 2 more servos, and receiver. So far it is at just over 12 oz... Don't see a problem getting under 20 with the 'HEAVY' OS10.
Don,
just as a follow up to my PM on the Pico's electric power setup, the finished airframe (a combination of Monokote, Ekonokote and Ultracote) came out at 14 oz if I remember correctly (I'd have to check the build thread). Unfinished it was 12 oz with fully sheeted foam core wings and stabs. I was optimistic for a 26 oz AUW model but it ended up weighing 30 oz with the somewhat heavier 3s 25C 2350 mah lipo. The battery alone is ~7 oz and I could use a 3 oz lighter one at 15C 2100 mah which would lower the model to 27 oz AUW. Of course that would be ideal but without the heavier battery the model is tail heavy which is largely attributed to the sheeted foam stab and built up airfoiled fin and rudder. If the design was modified to stick construction empennage then one could even use 1350 mah lipo's for a very light model but in their absence, the model ended up weighing twice as much as the finished airframe.
I still don't know how well she'll fly but as AndyW points out, it will be fast and will likely not slow down that much for landing. In any case, that's ok as the plane was a bit of a proof of concept as well as a bit of eye candy in my shop (to me) and inspiration. As a result of the build I can think of several things that would help to bring the model in at it's ideal 26 oz AUW while at the same time balancing correctly. I don't think that the 40" airframe could weigh much less than 12 oz and still look like a Tiporare as well as of course being true to the plans in concept.
In any case, inspired by AndyW's little Tsunami a few months ago, I expect to built one just about the same size (many of the parts are already cut) as his (a tad larger) with retracts and the same motor that's in the Pico. I expect the model to be even lighter than the Pico by design even though it's a tad larger. I imagine it will also have a ~30 oz AUW but will have lower wing loading since the wing area is a fair bit larger. It will also be able to land on wheels rather than belly land as the Pico will.
Keep up the good work and please do show us your finished kit prototype of the Eyelash. I think I'm developing quite a taste for these smaller classic birds.
David.