Misc Coaxial Rotor Thrust

[Alexander8046]

Hi
Im looking to build a copter with coaxial motors like this:
View attachment 17211

I wanted to know how much relative thrust I could achieve on each arm
eg.
My motors can produce 1.2kg of thrust and I wanted to know what the thrust would be if I attached them coaxially.
I'm not interested in efficiency yet; I just need the thrust.
Thanks

 

[Smoggie]

Alexander,

The attachment is invalid so we cant see the photo.

A coaxial has two counter rotating rotors on the same shaft.. is that what you have in mind? Calculating thrust is very complicated, you cant really say 'a motor can produce X amount of thrust' because it very much depends on what size rotor/prop that the motor drives. But having said that, if you had two props (each producing 1.2Kg of thrust independently) and you put them in coaxial layout running on the same shaft I'd expect that you would get somewhere around 1.8 of thrust (give or take). You lose a lot of efficiency (and thrust) vs having the props working on their own.