Electric Helicopter designs?

[SmartS=true]

I just started playing KSP again, and I wanted to build a basic electric helicopter. Nothing too complex, just one that could lift off of the ground. I tried building a rotor for several hours, but none would lift off unless I hacked gravity. I can't find any tutorials or ships to download, or any forum threads that explain the design of one in detail. Can someone who has built one give me some tips?

[Signo]

I think you should start here.

Good luck.

[LN400]

Which parts mods are you using and which special (like rotating) parts are you using? A picture and some words on your contraptions so far would also be of great help.

 

I can say this though: Using Infernal Robotics and Procedural Wings I did manage to build a somewhat controllable twin rotor heli. It has since been scrapped but I do remember it was quite the challenge to make the wings and rotor system strong enough for the neccessary high rpm. No hacks were used.

 

I don't know how much you are into helicopter design so a few words on where you come in that respect from would also be good info.

 

That said:

There are in essence 2 different approaches you can take. One is mechanically simpler but can be harder to control. This is the type where the angle of the wings relative to the oncoming air is fixed (fixed pitch) and only rotor rpm can control climb/descent.

The other type is much more complex and involves some way of changing the wings' angle of attack (collective pitch) to control climb/descent with a fixed rotor rpm.

Which one of these 2 have you been working on?

 

Edited August 1, 2016 by LN400

[SmartS=true]

27 minutes ago, LN400 said:

Which parts mods are you using and which special (like rotating) parts are you using? A picture and some words on your contraptions so far would also be of great help.

 

I can say this though: Using Infernal Robotics and Procedural Wings I did manage to build a somewhat controllable twin rotor heli. It has since been scrapped but I do remember it was quite the challenge to make the wings and rotor system strong enough for the neccessary high rpm. No hacks were used.

 

I don't know how much you are into helicopter design so a few words on where you come in that respect from would also be good info.

 

That said:

There are in essence 2 different approaches you can take. One is mechanically simpler but can be harder to control. This is the type where the angle of the wings relative to the oncoming air is fixed (fixed pitch) and only rotor rpm can control climb/descent.

The other type is much more complex and involves some way of changing the wings' angle of attack (collective pitch) to control climb/descent with a fixed rotor rpm.

Which one of these 2 have you been working on?

 

I have been working on one with a fixed pitch.

[LN400]

1 hour ago, SmartS=true said:

I have been working on one with a fixed pitch.

Alright. That does simplify things. 2 things to keep in mind.

The angle of the wings first. Too great angle and the wings will stall if the stress doesn't break the whole thing, too little and there won't be enough lift. Only experimentation on a given design can give you your optimal angle in KSP, I would think but also bear in mind that typically, the angle really doesn't have to be great at all. 5 degrees perhaps, perhaps 3-4 will do, 10 tops before things start to go south, could be a starting point.

RPM. Fast does it. Very fast even. Consider real helis with their perhaps 300-400 rpm, or model helis with their 2000-5000 rpm. Wobbles and total disinteration will threaten but work on making it sturdy yet as light as you can.

One more thing. Helis (even DIY ones in KSP) are really demanding when it comes to perfect balance. Put a say, 50 kg part on only one wing as it spins at say 500 rpm and watch the ensuing mayhem. Shouldn't be to much of an issue in KSP with parts copying and symmetry mode but definitely something to keep in mind.