Advice on helicopters?

[Genius Evil]

I've been working on this helicopter-type vehicle as part of an Eve lander

It's barely pilotable on Kerbin, and on Eve it crashes in seconds. (The navball marker spirals outward uncontrollably.)

Does anyone have any suggestions? The rotor rotates on an Infernal Robotics free-moving docking washer.

Edited November 10, 2013 by Genius Evil

[Taki117]

Have you taken a look at the Firespitter add-on? It adds all sorts of helicopter parts.

[Genius Evil]

Yes, I have it actually, but I wanted to see if it was possible with stock wings. Plus I doubt my computer could handle a craft with enough RTG's to power the electric rotor.

[ferram4]

Try tilting the tips of the rotor up, so that the rotor tips are above where they connect to the hub. The way it's currently set up, if it ends up off vertical the differences in blade angles will cause it to go further off of vertical. Tilting them the other way should cause it to remain stable.

That said, this probably isn't going to work.

[M5000]

I'm not sure if you can apply this to KSP, but I think a fundamental in helicopter design (eg: using a rotating wing to generate lift) is that you'll almost always need two rotors. One to provide the lift, the other to counter the spin that the main rotor (or other same-sized rotor in some cases) causes.

For example, the traditional helicopter design consists of a large rotating blade to provide lift, and a smaller, tail-mounted blade that spins to move air to counteract the spin naturally induced by the main rotor.

Examples:

AH-64 Apache

MI-17/MI-8

MI-24

UH-60 Blackhawk

You get the idea.

However, just because you have two rotors, does not mean you have to put one on the tail vertically mounted. You may be able to get by with a dual-rotor design where both rotors are nearly equally sized. Designs that use this way of dual-rotors are...

CH-47 Chinook

CH-46 Sea Knight

H-21 Workhorse "Flying Banana"

MV-22 Osprey (Albeit not a true helicopter, in VTOL mode it uses the dual rotors in this manner.)

Even still, there's another way you can avoid using a tail rotor. Some design houses, such as Kamov in particular will use two rotors that counter-rotate (read: rotate the opposite direction) that are stacked on top of each other. The two I'm most familiar with are:

KA-52/KA-50

KA-137

Just google those designs and you'll see that helicopters are a bit hard to do without having dual rotors. I'm not a flight engineer but I think this may be intrinsic to a successful helicopter, you need a rotor to stabilize your copter.

[Genius Evil]

Thank you! It's stable now. If it works, I'll post a thread about it.