Why my rocket lose it's fuel tanks at launch pad?

[Pawelk198604]

 

And how to make good rocket makes it's way to the Mun, hopefully with MEM ( as in Munar Excursion Module  ) later one  

[Scarecrow71]

The first piece of advice I can give you is to be explicit with what the problem is, and then create a video that shows ONLY THE PROBLEM.  9 minutes of watching you move around the VAB with no real action doesn't tell us what's happening.  Not to mention that you showed the launch pad twice for a total of 30 seconds.  Fill us in on the point of the problem, and stick to that.  Please.  We can't help you if we don't know what is going on.

With that said, my primary guess is that the tanks simply aren't connected to the central stack.  Check connections, including any radial decouplers you are using.

[The Aziz]

There aren't any decouplers. I'd use them. And it looks like the fuel lines may be causing some of the tanks to fall off?

Btw the length of that rocket is enormous and you barely have 1.07 TWR at launch. You'd be better off with a single mainsail than 7 skippers.

[magnemoe]

One issue I had in KSP 2 is that sometimes an standard ship class I have sent 8 interplanetary might disintegrate on launch because reason. 
Now this is not totally unrealistic  

[Superluminaut]

KSP2 uses a confusing sub assembly thing. It may that the tank somehow exists without being attached.  I would recommend deleting the side tanks and using the symmetry tool to attach a new set to the center core. Good luck!

[Pawelk198604]

i just used cheat mode to add science and created this one   

 

 

[Vanamonde]

My first suggestion would be to simply build smaller rockets.   But if you want to go big, you'll need some strut reinforcement.