Orange Sherbert

Day 1 of testing! Tail heavy & CG issues. Check out the rocks I taped to the nose!

Day 2 of testing. Never tape your elevons to the bottom of the wing like I did here or you'll have no elevator authority to perform any aerobatic maneuvers. Not being able to pull up out of a dive sucks!

Day 3 of testing. Unfortunately, the winds were pretty high gusting at 15mph. Not a good day to be testing a prototype wing. At least the elevons were fixed now.

Day 4 of testing. 5040 2 blade props instead. Crashed it into a tree at the end, but it came back

Introduction:

I wanted to build a wing similar to my mini rainbow as sort of a test platform to compare different electronics on. I have a spare mini rainbow still in the box, but I have a lot of motors I want to test and one spare wing just isn't going to cut it. I'm going to be pushing these out like cookie cutters outfitted with different electronics. I dug around the internet for plans when I came across the battlewing on a flitetest forum. The size was almost identical to the mini rainbow and it had some pretty impressive speed to it.

Components (~$25):

  • Mars Power 1806 2280kv with tri blade 5040 props
  • Turnigy 10a plush esc
  • 2x 3.7g servos & push rods
  • 4 gram micro receiver
  • various bamboo skewers for spars
  • 1 sheet Dollar tree foam board + orange tape

Conclusion:

The build wasn't tough at all, even though the plans didn't have too many details. Since I finished off the build with orange tape, I decided to name it the orange sherbert. I added two spars, one vertical and one horizontal. I considered this to be a prototype and I learned a lot from building it. The major mistake I made in the first build was taping the elevons to the bottom instead of the top of the wing. The gap pretty much killed all elevator authority (although it still had excellent roll rates) and caused a lot of crashes while doing aerobatics on 3s and not being able to pull out of them. Aside from that, the online calculator I used for CG was off by about a half inch which made it way too tail heavy. I have now learned to test prototypes on 2s instead of 3s batteries. It's ok though because I can build another one easily, right?

In any case, after I fixed the CG and elevons, it ended up being a great flier at about 130grams w/o the battery. It is not as good as the mini rainbow because I still had to put in some reflex in the wings to get it to fly level and I also had to use some nose weight to get it to balance. The mini rainbow requires no nose weight or reflex and thus the performance is superior. However, given the low cost, I can easily test the dozens of motors that I want to try out in the future quite easily. Even though I used very similar electronics as the creators did, I do not feel that mine flies quite as fast. My guess is that either the batteries need to be a higher c rating (pretty sure this is a factor) or the esc may not be able to keep up with the motor switching frequency (not sure about this one). Anyway, it's fast enough for my needs currently, so I'm not going to complain.

After 3 days of flight it has crashed at least 2 dozen times (in many spectacular ways). I've learned all the weaknesses now for the next wing (which is already under construction). To be honest, I'm surprised that the thing still flies, but I guess I built the thing pretty tough.