Sirantony

My Feedback: (15)

Sometime back I bought an Ikarus X-500-5 brushless motor esc combo. I am thinking of trying to install this setup in an ARF spacewalker by seagull models. Details of plane - w/span 61"
w/area 640 sq ins. weight incl. all radio gear - 4 lbs. Weight of electric power combo is 1lb 4 ozs. Motorspecs 6-24 cells,
amps max 40, prop to 11.5 x 7". with a 10 cell sub C pack all up weight would be about 7 lbs.
What are your thoughts on this project? Is it feasible. I am only interested in gentle sport flying. Sirantony

Matt Kirsch

My Feedback: (21)

10 cells at 40 Amps is 400 Watts. On a 7lb plane, that's less than 60 Watts per pound of aircraft. The plane MIGHT ROG, but I doubt it. Overall, performace will be lacking, even for gentle sport flying. On top of that, the wing loading (25.2 oz/sq ft) will be very heavy for such a light power loading.

e-bird

The kinda rule of thumb is 50 watts per lb for gental flying
the worst thing is feeding the 400 watts lota $ for batterys.
CU

Matt Kirsch

My Feedback: (21)

Yes, 50 W/lb for gentle flying, but the plane has to have a light enough wing loading. 25.2 oz per square foot is pretty heavy. You can't put a 400W power system into an 8lb GeeBee R2 with its fat fuselage and stubby little wings and expect it to fly, for example. Drag needs to be overcome, and drag increases as wing loading increases, I believe.

4lb for the plane itself is awfully heavy. It'd probably come out at around 6lb with a glow engine.

Okay, I went to Ikarus's website. Their recommended power setup is SIXTEEN cells, and a 295x180 propeller, which translates out to about an 11.5x7 prop. That's a good power setup for a .46 size