that hundreds of Dynam Skybuses have been flying around for quite some time now without leaving smoke trails all over the sky?
Apparently the key to success with longer ESC-to-battery wires is–other than adding capacitors–not to put excessive demands on the system. Tests with our watt meter showed these two 1100 KV brushless motors drawing 11 amps each for a total of about 22. However, the Dynam ESCs have a capacity of 30amp each. So very little stress is placed on them.
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Apparently the key to success with longer ESC-
Tricky Wiring on the Skybus
There are a couple of neat little wiring tricks that designers have put into the Skybus that we would like to show you:
When we first looked at the Skybus wiring we were not able to find the usual “Y” harness for the two aileron servos. Their aint none! At least not as we normally see a “Y” harness. On the end of the aileron wire leading
There are a couple of neat little wiring tricks that designers have put into the Skybus that we would like to show you:
When we first looked at the Skybus wiring we were not able to find the usual “Y” harness for the two aileron servos. Their aint none! At least not as we normally see a “Y” harness. On the end of the aileron wire leading
from the receiver there is a six-
Not Cutting the Red ESC Wire
On twins using BEC, as does the Skybus, standard practice is to cut or disconnect the red wire coming from ONE of the ESCs. This is to prevent the two ESCs from fighting each other. On the Skybus, by using an unusual plug, the designers have already done that for you. Look at the photo below. On the right side of the plug you see two red wires coming from the ESC. But on the left (going to the receiver), only one. Now that’s what I call design engineering!
Bench Test Predictions
Note that to simplify the math we round off all numbers to the hole.
Our Skybus ready to fly weighs 2 lbs, 8 oz. After 10 seconds the watt meter shows the twin motors drawing 22amps at 10 volts delivering 243 watts. Divide the 243 watts by the airplane weight and we get 97 watts per lb. That’s plenty for most scale airplanes.
The 2.2 mAh battery divided by the draw of 22 amps times 60 should theoretically provide 6 minutes of flight time. But the best we were able to get out of it was about 3 minutes. The two ESCs can not be programmed by the user, so I can only assume that the low cut-off voltage was set rather high at the factory. Just play’en it safe, I guess!
Our Skybus ready to fly weighs 2 lbs, 8 oz. After 10 seconds the watt meter shows the twin motors drawing 22amps at 10 volts delivering 243 watts. Divide the 243 watts by the airplane weight and we get 97 watts per lb. That’s plenty for most scale airplanes.
The 2.2 mAh battery divided by the draw of 22 amps times 60 should theoretically provide 6 minutes of flight time. But the best we were able to get out of it was about 3 minutes. The two ESCs can not be programmed by the user, so I can only assume that the low cut-
Adding a Second Battery for More Flight Time
