Hey,(adsbygoogle = window.adsbygoogle || []).push({});

Recently I have decided to attempt to create a helicopter on the cheap, just to see if I can make one and if it can fly "well". I have a friend who is going to help me with this, so I'm not alone, even though he's not helping with working out equations/the theory side of it.

So far, the main problem is that I don't know many equations that can help with building a helicopter - I know what I need to work out, just not how.

I've done this mostly in metric, as I find it easier to work with than imperial measurements.

So far I know the Lift Equation (L=1/2*Ad*V^2*Sref*Cl), and so far I have this:

L=1/2*1.2*3.125*9.8*188.4=2884.875 Newtons

2884.875/4.5=641lb

(4.5 Newtons is the amount of force needed to keep a pound hovering constantly)

I'm planning on having the circumfrence of the rotors as 6.2m, and the axle (or shaft, whatever floats your boat) it's attached to as 0.05m in circumfrence, so as I thought that the aircraft velocity was just the rotors for a helicopter (as that's the only thing moving to make it fly), so I added them together and halved it (I didn't multiply it by the time it would travel round, as I am expecting it to travel the whole circumference in one second) for the aircraft velocity - Is this the correct way to do it? I was guessing at this, as I couldn't find anything to help me on Aircraft Velocity.

Also, this is with the angle of attack at 30degrees. I think this should be the max angle it can go up to, as I am thinking of somehow making the angle of attack adjustable.

So I have 641 pounds to work with, if my calculations are correct.

I'm not entirely sure on this... I mean, I need to know the dimensions of the rotors as well, don't I? That should affect flight I would think.

So does anyone have any equations that I need to help work out what I need? I don't know what engine I'm going to be using (I'm expecting around 70-100hp) and also I don't know how much.

So thanks for looking, If I haven't explained anything very well please tell me and I'll try to re-explain ;)

**Physics Forums - The Fusion of Science and Community**

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Aerospace Helicopter Equations?

Loading...

Similar Threads - Helicopter Equations | Date |
---|---|

Aerospace Helicopters and operational height limits | Jan 9, 2017 |

Is 'Airwolf' possible with our current technology? (Supersonic Helicopter) | Jun 9, 2016 |

Propeller and thrust | May 7, 2016 |

Helicopter Winch - Rope Arranger About Rotating Cylinder | Mar 22, 2016 |

Aerospace HELP ME - Lift equation for Helicopter Fan | Dec 2, 2012 |

**Physics Forums - The Fusion of Science and Community**