Ship with enough TWR frozen mid air.

[Problemless Mods Wanter]

Hello,

Before going into detail of installed mods, craft and log files, I want to collect some opinions on this issue.

I have a big ship (Station core) with 285 parts, 3,598 tons and 45mx35mx35m. It has enough TWR. It is being launched with clamps, to avoid sticky launchpad bug.

I have launched way heavier and bigger things to orbit before, with almost same setups for years, so I wouldn't consider myself a noob in KSP. I recall having similar issues back in time, a couple of times over the years... But I ended up, just giving up and starting over. This time I want to solve this...

 

When I launch this ship, it just sits in mid air. Not a single centimeter of movement, down or up.

To make sure it wasn't a TWR issue, using the console menu, I lowered the Gravity of Kerbin to 0... 5x mutliplying the TWR  but still no movement. (Checking with MJ surface info)

To get even more precise info, I cheated it to orbit, without clamps parts. Full throttled both the solid boosters and the engines, not a single digit changes neither from Pe or Ap...

The ship won't even move using RCS or torque... It has a torque power above 14.000 with 3 toroidal R.Wheels from FTT. In fact those reaction wheels combination was the first thing I checked before going on the detail building spree, and they were working just fine. It's just LOCKED in place...

I tried;

• Removing all manual struts,
• Disabling all auto struts and rigid connections,
• Rerooted to mutliple different parts,
• Even changed the SAS part with different versions,
• Not to mention dozens of times of reloading the file, saving it as a different craft file, exiting entering building, directly launching from the pad, relaunching the game along with mutliple crashes...

 

So my question to you is, before asking any pictures, or mods info, or log / craft files, please tell me what will you be looking for, in those?

What may cause this issue? Is my ship (file) doomed to be broken and I have to start from scratch again?

What year is this?

 

 

[Superfluous J]

The first thing I'd look for is the thrust of the engines being blocked by the ship.

Then I'd look in the log for any errors.

It's 2019.

[Problemless Mods Wanter]

47 minutes ago, 5thHorseman said:

The first thing I'd look for is the thrust of the engines being blocked by the ship.

Then I'd look in the log for any errors.

It's 2019.

Thank you for your reply...

It has 9 engines in various places and 12 solid boosters... None of them blocked or covered in any way... 5 of the engines and all the boosters are at the very bottom.

But even if all or some of them were blocked, the ship would move slightly, in any direction. But as I said, when I release the clamps it just sits in the air not falling or going down, even with the engines off...

Also as I said it doesn't move / turn even in orbit, with torque nor RCS...

The logs do not pop any errors...

[Xt007]

I’ve had the same issue, my specific case turned out to be caused by a tweakscaled part.  I’d check if any of your parts have a negative mass.

[Problemless Mods Wanter]

38 minutes ago, Xt007 said:

I’ve had the same issue, my specific case turned out to be caused by a tweakscaled part.  I’d check if any of your parts have a negative mass.

This is an interesting theory. I'm loading KSP now to investigate.

But I have a lot of parts that are custom scaled. Is there a way or a mod, that I can use to see which part(s) in particular?

Without having to try out one by one....

[Problemless Mods Wanter]

2 hours ago, Xt007 said:

I’ve had the same issue, my specific case turned out to be caused by a tweakscaled part.  I’d check if any of your parts have a negative mass.

I opened up the .craft file looked for the word "mass"... I was about to write "A lot of the parts seem to have 0 mass" but then I found the culprit with: "modMass = -3.9460001"

It is a bluedog.LDC.S1.Tank2 which has size variations built in, which also caused me some issues in the VAB I earlier, I should have figured....

Ok I'm changing those tanks and see if it fixes the issue... Thank you so much for your contribution...

 

EDIT: I changed those tanks but still the same. Could those 0 mass parts also cause the issue?

Edited December 6, 2019 by Problemless Mods Wanter

[Problemless Mods Wanter]

Turned out to be the "PPD-MULT Multi-Point Station Connector" part from

Having this part rescaled with different switchable subtype (Elbow), created this negative mass issue.

Removing the part, unlocks the ship.