Ladder Physics and Glitches

[Andrew Hansen]

You may or may not have heard about this before, but there's a really fun glitch in KSP involving ladders that allows you to go to achieve infinite delta-V and a high TWR by simply climbing up a ladder with a Kerbal.

To get this glitch to work, the Kerbal has to have something to push his head against as he tries to climb up the ladder. A phantom force will be generated whenever the Kerbal pushes on that object with his head, and is strong enough to cause small crafts to levitate off the ground. Of course, the "small crafts" bit is crucial. Even if the craft looks light, it has to be really light if you want to overcome Kerbin's gravity. Thankfully, the vast amount of massless parts in KSP means you have a nice selection to work with in creating ladder-powered vehicles.

Anyway, if you're familiar with this glitch and have used it for something, please post below and show off what you did. Technically, it should even be possible to to go Eve and back with this glitch (or perform a grand tour)!

If you just want to download a pre-built craft that can utilize this glitch, then click here. Below is a video demonstrating how this glitch works and an example mission to the Mun and back.

UPDATE: Here's another video by TW1 of an Eve ascent powered by ladders.

And then one by me where I travel from Kerbin to Eve, then to Gilly, and back to Kerbin again.

Edited October 6, 2014 by Andrew Hansen

[MiniMatt]

That's quite special Have a little +rep nod

[Andrew Hansen]

That's quite special Have a little +rep nod

Thank you very much! I hope to take this craft to Eve and back sometime.

[Franklin]

stock aero is so unrealistic!! >

[BagelRabbit]

Sorry Andrew, but you've been beaten to a Eve SSTO. (not by me though, so I can't take all credit)

That being said, I'm definitely going to make a video on this in the near future... stay tuned

[Andrew Hansen]

Sorry Andrew, but you've been beaten to a Eve SSTO.

That's awesome! Thanks for sharing! There's still not many videos that I know of about Eve SSTOs, and he didn't land on the surface, so I could still try that. But now I know it's possible, so I'm inspired. I'll be looking forward to your video.

stock aero is so unrealistic!! >

This is actually possible in space, so it would work with Ferram Aerospace Research too.

[Levelord]

stock aero is so unrealistic!! >

Its not just the aero, the ladder glitch works in space too.

[Franklin]

Yeah I was being sarcastic. This is just a fun bug.

[GusTurbo]

This is basically how the EM Drive works.

Edited October 2, 2014 by GusTurbo

[Andrew Hansen]

This is basically how th EM Drive works.

Except that this drive is thousands of times more powerful. The EM drive could never overcome the earth's gravity. Honestly, it would be nice to get this bug fixed, since having access to cheats like this takes some of the fun out of building realistic SSTOs. I mean, sure, you might have built an awesome SSTO, but what's the point if you can do the same thing in a craft that's so much tinier?

This reminds me of the

.

[dryer_lint]

Honestly, it would be nice to get this bug fixed, since having access to cheats like this takes some of the fun out of building realistic SSTOs.

Except for the fact that this bug is obviously a cheat and using this to get to orbit doesn't really count. At all... unless you're trying on purpose to glitch exploit.

[astropapi1]

Except that this drive is thousands of times more powerful. The EM drive could never overcome the earth's gravity. Honestly, it would be nice to get this bug fixed, since having access to cheats like this takes some of the fun out of building realistic SSTOs. I mean, sure, you might have built an awesome SSTO, but what's the point if you can do the same thing in a craft that's so much tinier?

This reminds me of the

.

TONY PROBE!

Damn, it's been a long time.

[Andrew Hansen]

Except for the fact that this bug is obviously a cheat and using this to get to orbit doesn't really count. At all... unless you're trying on purpose to glitch exploit.

It totally counts unless you purposely define using this bug as a cheat. You have to impose that limitation on yourself, since the game doesn't do it. I believe the game should be balanced, and not have some options that are far superior to others in ways that don't make sense.

Just like infinigliding. Sure, you could built a rocket-powered plane to explore Eve with limited range, but you can explore just as easily with a lighter, infinigliding craft. It shouldn't be that way. Of course, someday the developers will work on updating the aerodynamics after they reach Scope Complete, but hopefully they'll fix this ladder glitch as well.

[Geschosskopf]

Anyway, if you're familiar with this glitch and have used it for something, please post below and show off what you did. Technically, it should even be possible to to go Eve and back with this glitch (or perform a grand tour)!

I think Tw1 is the master of this. He went to Eve and back on a ladder.

But on a personal note, I sincerely hope this glitch NEVER gets fixed because I find it quite fun to play with. Also, I consider it quite realistic provided you don't use it for space travel. I use it all the time as pedal-power, a bicycle mechanism. Seriously, here in the real world, we have ground vehicles, water vehicles, and even airplanes moved solely by human muscles. I own a bicycle, a rowboat, and a pedal-powered kayak myself.

So why not in KSP? I thus make very light amphibious rovers and aircraft using the ladder glitch. All very useful and fun to play with. I know I could take them to Eve and back but I refrain from that because I got KSP to play with rockets. But having a pedal-powered vehicle means no worries about fuel or electricity, and the Kerbals need the exercise after spending months inside a small spaceship gorging on snacks .

[Guest]

I'm not entirely sure if or how this glitch can be fixed but massless, insignificant parts probably don't help. Maybe when Unity 5 hits, if there are significant performance gains the perceived need for such parts will be eliminated.

[cantab]

Personally I hope the ladder glitch gets fixed as part of a general physics overhaul, that would cure other bugs too and improve things generally. A special ladder-fix isn't really needed, it's a generally harmless and easily avoidable glitch. (Unlike infinigliding, which is impossible to avoid without completely abandoning control surfaces, thus making it harder than it should be to make an honest ion glider.)

[Red Iron Crown]

Just like infinigliding. Sure, you could built a rocket-powered plane to explore Eve with limited range, but you can explore just as easily with a lighter, infinigliding craft. It shouldn't be that way. Of course, someday the developers will work on updating the aerodynamics after they reach Scope Complete, but hopefully they'll fix this ladder glitch as well.

I would say there's a qualitative difference between the ladder force and infinigliding exploits. Ladder force requires you to actively try to exploit the glitch and isn't something that will happen accidentally in the course of normal operations, for most people's definition of "normal" anyway. Infinigliding, on the other hand, happens on every craft with control surfaces to one degree or another; for small craft with control surfaces it's hard to avoid it being significant.

It doesn't matter to me if ladder force is ever fixed as I never use that exploit, but infinigliding needs fixing if aerodynamic craft are going to function as intended.

Edit: Ninja'd by cantab saying the same thing more concisely.

[Guest]

It doesn't matter to me if ladder force is ever fixed as I never use that exploit, but infinigliding needs fixing if aerodynamic craft are going to function as intended.

Fixing the aero model, if done like NEAR/FAR at least, will implicitly fix infinigliding. That, or dealing away with massless, insignificant parts would greatly reduce the exploitability of both glitches.

[Red Iron Crown]

Fixing the aero model, if done like NEAR/FAR at least, will implicitly fix infinigliding.

Yeah, now that we're seeing some commitment from Squad to fixing the stock aero model, I'm reasonably confident the infiniglide glitch will eventually be closed up.

[Guest]

Yeah, now that we're seeing some commitment from Squad to fixing the stock aero model, I'm reasonably confident the infiniglide glitch will eventually be closed up.

Citation? Last I heard it "wasn't the nicest piece of code" and I certainly don't take that as commitment considering some of the production code I've seen that was never changed because "it does the job".

[Red Iron Crown]

Citation? Last I heard it "wasn't the nicest piece of code" and I certainly don't take that as commitment considering some of the production code I've seen that was never changed because "it does the job".

Maxmaps on reddit:

"If you want an official stance on aerodynamics; We know they need work, however for the alpha stage we feel like they are sufficient. Not great, just sufficient. Once we actually reach feature complete, then we'll absolutely look into them, see what we can and should fix to get them to a proper standard. For now, the team has to work on getting features that don't exist to actually exist, before we get to getting to improve things that currently exist but aren't great.

Tl;dr: We know aero isn't great. We'll get to it. Just not in 0.25."

Much less "maybe" and "we'll see", sounds like it's coming eventually. Best news in a while for the realism crowd.

Edit: He also confirmed that cargo bays will eliminate drag from parts within them, even in stock aero. This paves the way for useful fairings in stock, and perhaps a better aero model in general. He later said this wasn't for 0.25, but some later update, but the module is already written.

Edited October 2, 2014 by Red Iron Crown

[Andrew Hansen]

<snip>

Yes, if you set limits for yourself and use this ladder glitch for "pedal-powered" bicycles and airplanes, then it adds a lot to the game. It sounds like it would be fun making a ladder-powered rovers!

Maybe when Unity 5 hits, if there are significant performance gains the perceived need for massless parts will be eliminated.

That would be absolutely awesome. And the ladder glitch doesn't specifically have to be dealt with, but removing the PhysicsSignificance = 1 tag from parts (making them have actual mass) would make it very hard to build overpowered ladder crafts.

For now though, I'll exploit the glitches for fun and profit, and then tell myself not to use them when building actual realistic-ish SSTOs.

[Guest]

Best news in a while for the realism crowd.

Best news in a while for everyone else; the realism crowd will continue using FAR because I guarantee you SQUAD won't take it FAR enough. But it does mean I could play the stock game and not feel embarrassed for it.

[Tw1]

A discussion about my favorite glitch, and I almost missed it!

That's awesome! Thanks for sharing! There's still not many videos that I know of about Eve SSTOs, and he didn't land on the surface, so I could still try that. But now I know it's possible, so I'm inspired. I'll be looking forward to your video.

And here I am sitting on one ready to go. Screw sleep, I have KSP to do!

I think Tw1 is the master of this. He went to Eve and back on a ladder.

Technically, that flight was hyperedited in. This time I'll get there by rocket, though I have been to Jool with only ladder power.

Re Grand tour: Working on it. http://forum.kerbalspaceprogram.com/threads/70180-Attempting-to-voyage-through-space-the-Kerbal-ladder-engine-An-experiment-adventure?p=1282498#post1282498

Probably should get back to that, now I have a little time...

Edited October 2, 2014 by Tw1

[Red Iron Crown]

Best news in a while for everyone else; the realism crowd will continue using FAR because I guarantee you SQUAD won't take it FAR enough. But it does mean I could play the stock game and not feel embarrassed for it.

Maybe. Not everyone uses those mods, I don't use any physics-altering mods even though I consider myself in the "more realism" camp. It's good news either way though, an indicator that game mechanics will continue to be refined even though we're already "sandbox complete".

Stop raining on my parade, Spacehippie. =D