Even if throttle is at max position, my quadcopter is not flying more than 3 feet. why?

How to tune the copter for more stability? how to make it fly at higher altitude?

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There is an equation of thrust for all multirotors if you want it to fly at a decent height.

2x the weight of the copter divided by the number of motors is the thrust your each motor should produce.

Go through the tables of thrust for each motor. They have thrust readings for different voltage and prop size. After seeing the table just find which prop size or voltage gives the amount of thrust just needed for your copter and buy a set of props or a battery!

Vyger2 years ago

Let go of it.

-max-2 years ago

In short, do this:

1) Get a better battery (some people can get away with using something like NiMh tech, but that is far from ideal due to weight.)


2) Get bigger motors, larger props. (If the motors struggle to get up to speed with large props, and get hot, use smaller ones, with less pitch.)


3) Trip away all unnecessary weight (How many holes can you drill into the frame before it gets too weak? Perhaps use something other than solid steel? Like wood, or carbon fiber?)


4) Make sure it is not software, calibrate ESCs, check ranges, etc. (you may need to look for documentation on how to do that for your build.)

-max- -max-2 years ago

Oh, I forgot the obvious:

5) Make sure the props are not mounted upside down! (The airfoil shape of them should curl downwards, and the "blunt," fat edge should be cutting into the air when it spins the correct way, and the sharp, thin part should be moving away as it spins. I have made that mistake a few times, and it means really weak lift, if anything.)

Numbers on the prop should face "forward"

seandogue2 years ago

Since it's clear you're already achieving some elevated flight, here are a few quick possibilities

a) it's too heavy. Are you attaching something to it that impacts it's weight?

b) your batteries are worn out and not delivering enough power to the motors

c) your motors are damaged and worn out

d) your controller is worn and is not outputting the throttle signal beyond a weak value unsuitable for higher flight.

e) your copters internal wiring is compromised.

Naveen D S (author)  seandogue2 years ago
Thank you Seandogue.
Nothing is attached to the copter yet.
Battery and Motors are pretty new. So, they have'nt worn out.
There might be some error in initial adjustments. please tell me how to increase throttle power by varying the initial values in the transmitter and also how to calibrate the ESC.

Sorry, but with all due respect, it is not my job to cover the bases for you. Contact the company that sold you the speed control, since they know their product (the one you bought and the one they made money on) and exactly how to calibrate and maintain it.

Good luck, you're on your own

Your ESC will have come with an information sheet explaining how to calibrate it. (at least every one I have bought did)

Your flight board will also have a sheet or booklet. OR you can try watching some of the videos i linked to in my other post.

rickharris2 years ago

1. You don't offer enough information to allow much help beyond general comment.

2. If you are having height problems check:

The props are on the right way

The weight is not too much for the power of the motor.

The ESC is calibrated to give full power.

Your not limiting the power with some other electronics.



Lots of information there


Double check the ESC

-max-2 years ago

Show us pictures, give us specs, and other stuff to give useful answers. As others mentioned:

1) The #1 rule in electronics: Thou shalt measure potentials! (measure the voltage to ESCs, make sure it is correct. Do that while the motor is driving the prop, and MAKE SURE that the prop is not close to shredding anything, and the whole quad is really held down to keep from going anywhere.) If the voltage is not sagging a lot from what it should be, and it is close to the rating of the ESCs (1S = 3.3V-4.2V; 2S = 6.6V-8.4V; 3S = 9.9V-12.6V)

2) What props are you using, what motors, and how much does it weigh? Do you know if the motors and props are well-matched? How much static thrust can the motor create? You can find videos online for the ballpark calculations, and common sense as to what will work is also good. Obviously you will not be lifting 1000g with the small hubsan X4 propellers using 4 drill motors.

3) Are you sure you have calibrated the ESCs? There may be a mode in your flight controller to allow it to directly control the ESCs though some input, and just map the input range to the set output range. (In multiwii, there are throttleMIN and throttleMAX values you can set, as well as MID, and things like gain. Adjust the MAX to be higher than whatever it is set to. By default, it will probably be 1000-2000, with 1500 being the middle.)

There are plenty of good resources on the internet to find information of doing that properly. MAKE SURE TO FOLLOW THE DOCUMENTATION CLOSELY, DO NOT CALIBRATE WITH PROPS ON. (When I first "calibrated" my ESCs, it turned out that in fact, I did no such thing, and actually entered programming mode and changed stuff I was not supposed to change!)

Ploopy2 years ago

Maybe your batteries/motor drives don't have enought current to lift the quadcopter?

Ploopy2 years ago

Maybe your batteries/motor drives don't have enought current to lift the quadcopter?