# Aerospace How much power do I need?

1. Dec 16, 2011

### goral09

Hi everyone,

I'm thinking about building x-ufo helicopter, and I'd like to know how strong motors I need. I've been looking for some info in the internet but didn't came across anything interesting. Can you help me and show me a book or a site where i can find some tips and infos

I want to lift 2-3kg helicopter.

I know that if I want my helicopter to lift it has to have greater acceleration than g = 9.8 m/s^2, if I want it to stand still motors have to produce enough power to balance the gravity. But these are the most basic laws, what next?

Last edited: Dec 16, 2011
2. Feb 19, 2012

### Belginator

Hi there goral09, if you want to lift a 2-3 kg helicopter you need a minimum of 20 - 30 N of lift. Your helicopter doesn't need an acceleration capability of 9.8 m/s^2 technically as that's factored into the Weight, which is W = mg. So in order to hover your Lift needs to equal Weight (W). I can't really help you out on the motors though. You could maybe test a few motors with a prop, and have it pull on a spring scale to see how much thrust is produced, and then deduce how many you would need.