Help! I want to make a RC Plane with at least 50mph speed.

Sam Kh

New member
I am currently planning to create a fast RC plane with a sleek V-shaped design, which I find really cool.

However, I have a question: Can a 2300kv motor make the plane faster? My design is simple yet aerodynamic, featuring a single propeller.


For the build, I am using a FS-CT6B transmitter, a 30A ESC, an 11.1v 2200mAh battery, and a few servos. Can this setup help me achieve speeds of around 50mph?

Kinda like the one below..
 

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quorneng

Master member
Sam Kh
I am afraid you are missing the understanding of kV. It determines the RPM the motor can achieve for a given voltage but it does not determine the power of the motor. Both a tiny motor or a big powerful one can have the same kV.
It sounds like you have a motor in mind. What is its recommended max amps? This will give an idea of the power available. Battery Volts x max motor amps = Max motor power in Watts.
With such a figure it may be possible to judge whether you are in the right ball park to achieve 50 mph.
The answer is probably yes but there are many other factors that have an effect like the weight of the plane, it aerodynamics and the pitch of the prop.
How are you going to measure the plane's speed?
 

Merv

Site Moderator
Staff member
...Can a 2300kv motor make the plane faster? ...
As others have said, 2300kv motors come in many sizes. The watts a motor uses compared to the size of the plane that we are missing. To go fast, get a motor that has 200 watts or more per pound of the plane. When you weight the plane, include everything, the battery, motor, everything. It's the all up weight (AUW) as it is flying that you are looking for.

When it comes to kv think transmission. A high kv motor (2300kv) is like high gear. Lots of top end speed but low lugging power. A low kv motor (1000kv) is like low gear. Lots of lugging power but limited top speed. In electric motor power is measured in watts. In gas engines power is measured in horsepower. A race car and a tractor may both have 500 Hp. The race car goes fast and the tractor will pull a heavy load. It all depends on what speed you want the power to be used.

If we take 2 motors with the same watts but different Kv. The high Kv motor will need a smaller diameter prop, it will have more top end speed but less thrust when sitting on a thrust stand. The lower Kv motor will use a larger diameter prop, have more thrust on a test stand but lower top speed.

The bottom line, Yes, a 2300 kv motor, provided it has enough watts, will make your plane go fast.
I'm using a 2200 3S battery, 2600 Kv motor, pulling 50 amps. I think my plane is going 70 mph or so but I have not measured it.
 
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Shurik-1960

Well-known member
You can make your model flying at a speed of 50 miles or more.But you asked the wrong question. Your topic should sound like this: "Help me pick up an engine for my model" And further along the text: "My model is in the photo, its flight weight will be.... gram, span-.......cm, wing profile -......, the thickness of the wing profile in the center- ........mm, the thickness of the profile at the end of the wing-.... mm. The material from which the model is made is EPP or fiberglass." KV with a large value is taken for small 3-bladed propellers, and the brand of the motor is selected according to the weight of the model and the desired thrust. The greater the thrust, the greater the weight and speed of the model.Even a brick can fly with a strong motor.
 

Piotrsko

Master member
Somewhere on this forum was a rule of thumb for motor sizes, weight and relative speeds that went like this motor makes this much thrust so will power a craft about this weight. There was also another set of ROT that indicated a grouping of thrusts required for different types of aircraft flying by weight (power density)