Help! help for motors and propeller

semih

New member
Hello, I want to build an F22, but I don't know what to buy for the engine and propeller, but I have come to a decision. I will use Sunnysky CCW 980kv and 9450 propeller. Are this motor and propeller sufficient for the F22 model (3s has 11.1 volt lipo battery) please help me.
 

joelspangler

Active member
That depends on the scale of your F22. You can certainly size your model to work with the thrust that you'll get with the motor/prop combination. I'm not positive what exact motor you're talking about - is it this one? https://www.quadkopters.com/product/brushless-motors/sunnysky-2212-980kv-v2/

If so, the specs seem like a 3s battery would be good with a 9450 prop - they don't provide the exact info on that prop, but it would be somewhere in between the 9047 and 1047 props. Looking like it would pull somewhere around 11-13 amp, and give you somewhere around 740 - 870 grams of thrust. You'll need to determine if that's enough for the model you'll be flying and the type of flying you want. If you want it to be slow flier, something like a .6 to 1 weight ratio (thrust to weight) would be ok (meaning all up weight at ~1200 grams or less would be your target). If you want speed and unlimited vertical, you'd want something like 2 x 1 ratio, meaning your all up weight would be somewhere around 400 grams.

If I chose the wrong motor model, look up a chart for the actual motor you're looking to buy for expected thrust, and do the math for how heavy of a build you can get away with.
 

semih

New member
Yes, this is the engine and when I calculated the weight of the plane, I realized that it was about 680-700 grams and I want speed. An aircraft of this weight will most likely move slowly. Thank you for your help, I think I will look at motors between 1400kv-2200kv, when I researched these motors I thought they would be more suitable.
 

quorneng

Master member
semih
Be aware that kV is not a measure of motor power only the speed it runs at for a particular voltage.
For a brushless motor its maximum input power (Watts) is almost directly proportional to its weight.
However higher kV motors of the same physical size and weight do tend to be a bit more powerful but are turning smaller less efficient props so nullifying some of this power advantage.