Recovery assets and helicopter advice

[Scrogdog]

I’m a pretty boring player. Two weeks in and I have not even attempted to leave LKO.

Mostly I am developing assets in a practice universe. I want to run a capsule based program.

One of the things I’d like to do is recovery. For example, I know that Kerbals can EVA and swim after splash down. So, a seaplane can recover pilots.

In addition, I plan on a helicopter or some sort of VTOL craft using the winches from the Kerbal Attachment System to recover the capsules. No question that this is the most difficult part for me.

I’m not an aerospace engineer that much is clear. But it didn’t seem like it would be all that hard to build a helicopter. Well, I’ll tell you, it is not easy.

I’m wondering if KSP may not be chopper friendly in the same way that shuttles aren’t.

Or perhaps there’s a better mod to try than Firespitter for this purpose.

The biggest issue is with CoL acting strangely. When I first put the main rotor on directly over the CoM, the CoL was sort of in the ground and off to the side. I couldn’t figure out how to affect it other than by putting fins on. This raised it up and I could see the whole ball above ground, but the direction of the arrow was not straight up. It was angled a couple of degrees to the right. No matter if I moved the fins along the fuselage to a new position, that angle was not affected. It was also not affected by rotating the part in any manner.

In addition, there is a noted lack of helicopters on the boards that I’ve seen. One that looked good is a bit old and I could not get it to work.

So, what do you guys think? Should I scrap the chopper idea and just go rocket powered VTOL of some kind? Seems like that, in turn, might need a mothership or naval ship to get it close first.

Edited May 29, 2013 by Scrogdog
typo

[Eric S]

After flying a helicopter built with Firespitter, I realized that capsule recovery was going to be a royal pain if I tried that.

My current plan, which I haven't actually tried, is to use Hooligan airship parts and KAS winch parts to do recovery. It won't move as fast as a helicopter, but it still moves faster than a rover, and if you use solar panels and electric props, your pickup range is limited only by your patience. Biggest problem is you'll need to use the fixed solar panels or RTGs, as the animated solar panels won't survive even slow airspeeds.

[Scrogdog]

Nice idea! I'll check out Hooligan right away!

Thanks!

[zack2014]

The COL is only for wing-based parts.

For helicopters, you want to check the Center of THRUST. Because that's how FS works, it's an animated engine, rather than a true blade system.

But yes, they are hard. Luckily though, Snjo has included several "helper tools". Namely, the "hover" and "Kill Velocity". Both of which help immensely, especially in a crew/capsule recovery system.

[colmo]

Helicopters are hard. Here's a few tips:

- Don't use anything that generates lift or much drag apart from the rotors. They just make the craft behave strangely.

- Perfectly align CoM with CoT, the centre of your fuel tanks (the TAC fuel balancer should help if you use multiple fuel tanks) and the winch. This prevents CoM from shifting with fuel use or lifting cargo.

- The chopper should be able to lift off with about 1/3 throttle. If it needs more, it's underpowered.

- MechJeb's SMART A.S.S. is helpful in preventing sudden loss of control. Especially useful while concentrating on winch work.

Edited May 29, 2013 by colmo

[Scrogdog]

Thanks for the tips!

Even if I don't make a recovery chopper at some point I'd like to build one just to do it.