Here's the plan: take the basic design of the Sig MidStar 40, shrink it to 75% of the original size, close the nose, add in two engine nacelles on the wings, power it with a pair of brushless motors, draw it all up in CAD, get a short kit laser cut, and build the plane.
Should be done by the weekend.
Plan set from Sig arrived in yesterday's mail. I only wish the other plans services were that fast! Today I had them copied at 75% of original size, two sets. I've guesstimated the weight of the smaller airframe, figured the new wing area and span, and plugged it all into MotoCalc to come up with some motor/ESC/battery combinations that would work. A quick email to HeadsUpRC yielded less expensive alternatives to the OS motors suggested by MotoCalc (basically, I can get the needed two motors for less than the cost of one OS). I'm going with Master Airscrew 8X6 three blades, counter rotating - mainly because I think three bladed props look cool, but also because they will give me some extra ground clearance for the field, where the grass can be a bit long at times.
Tonight I'm going to start working with the CAD program to get the engine nacelles figured out - right after I get my better half calmed down when she sees me unrolling yet another set of plans.
Posted by StayQuiet |
Apr 23, 2012 @ 10:18 AM | 2,399 Views
I had a lot of fun with my Demi Duster project, but that twin engine dream keeps nagging me.
Our club field isn't exactly perfect yet (it's a work in progress) so there are some issues flying small taildragger electrics from it. Wheels tend to get caught in grass (or dirt) clumps, and the plane noses over on rollout.
I'm thinking tricycle gear. Years ago I flew a Sig MidStar 40 (glow) and enjoyed the plane. Rather than build a kit and convert it to electric, I'm thinking of getting a set of plans from Sig, having them copied at 75% of original size, for a wingspan of a bit under 48.5", closing off the nose, and adding in two motor nacelles on the wing. Draw it all up in CAD and have a short kit laser cut. Think of the offspring from a Hobbico Twinstar and the Sig Midstar 40 at 75% original size - a Twinstar 30?
My wife is going to kill me when she sees me building another one.
It's done! The canopy came out better than expected. CG is perfect, and it's all set for a maiden flight - as soon as I feel as though I can handle it. Maybe a buddy box flight with someone with a lot better flying skills than I currently have wouldn't be a bad idea.