Payload that flips every rocket, please advice (solved)

[Baker_02]

I have been playing ksp for a while, and been able to build stable rockets and sends satellites with no problem. But somehow I am unable to send this rover. It flips every rocket I have, even a 300t rocket I sent a palyload to sun. I spent several hours with different ways how to make it work but nothing. 

Image: https://ibb.co/fD0gsQT

File: https://easyupload.io/giev8i

Edited January 13, 2022 by Baker_02

[HebaruSan]

35 minutes ago, FleshJeb said:

Is your probe core upside-down? Look to see if it's showing brown as up.

Yup, that's it:

[FleshJeb]

20 hours ago, Baker_02 said:

I have a second probe on the rocket and the on on rover is deactivated for the duration of the flight, and hard to tell what is upside down because probe has one position to rover and second to rocket ..... but anyway I deleted the probe on the rover and now the rocket fly as stable as with any other cargo I have. Thank you for help your help

You can click on several types of parts and hit "Control from Here", and it will reference the controls to that direction. A few of the probes and command pods have different axes you can pick from, like Up or Forward. This also works with docking ports.

[steuben]

Forgo the gravity turn. Just luanch straight up and turn right.

[Baker_02]

Quote

Forgo the gravity turn. Just luanch straight up and turn right.

Nope this literally turns the rocket two seconds aftert launch to the ground, regardless of SAS or mechjeb, or twenty reaction wheels 

Edited January 12, 2022 by Baker_02

[Vanamonde]

Everybody makes fun of me for doing this but it works: spam the bottom of the rocket with fins, including entire wing parts, if need be. 

[FleshJeb]

9 minutes ago, Baker_02 said:

Nope this literally turns the rocket two seconds aftert launch to the ground, regardless of SAS or mechjeb, or twenty reaction wheels 

Is your probe core upside-down? Look to see if it's showing brown as up.

Fins are far better than reaction wheels. I rarely use more than what's on the payload.

[Baker_02]

1 minute ago, Vanamonde said:

Everybody makes fun of me for doing this but it works: spam the bottom of the rocket with fins, including entire wing parts, if need be. 

I spam it with twenty reaction wheels, plane wings, put the center of gravity down, but nothing two seconds after landing it flips. The problem is not with my rockets, I tried several rockets that never flipped with other cargos. Try the file for yourself

Just now, FleshJeb said:

Is your probe core upside-down? Look to see if it's showing brown as up.

Fins are far better than reaction wheels. I rarely use more than what's on the payload.

Yes I have putted fins on the rocket, really I build like two hundred rockets already and such behavior haven't happened. It's the cargo not the rocket that causes the problem

[HebaruSan]

35 minutes ago, Baker_02 said:

File: https://easyupload.io/giev8i

7 minutes ago, Baker_02 said:

Try the file for yourself

What part mods do we need? I recognize kOS and MechJeb, but I'm not sure about HitpointTracker.

[FleshJeb]

4 minutes ago, Baker_02 said:

center of gravity down

"Pendulum Rocket Fallacy". Center of Gravity wants to be as high as possible.

https://www.wired.com/story/lets-unpack-the-pendulum-rocket-fallacy/

Just now, HebaruSan said:

HitpointTracker

Should be BDArmory

[Baker_02]

Yes it is BDArmory, but the parts I used in that rover/cargo are stock (at least from what I remember)

[18Watt]

12 minutes ago, Baker_02 said:

put the center of gravity down,

What @FleshJeb said.  You want the COM as high as possible.

I also like to set the tanks flow priority so that fuel is burned from the bottom tanks first, ensuring that my CoM goes up as I burn fuel.

19 minutes ago, Vanamonde said:

Everybody makes fun of me for doing this but it works: spam the bottom of the rocket with fins, including entire wing parts, if need be. 

I normally don’t need a lot of fins, but when I do, I just keep adding them until the rocket flies acceptably.  The question ‘is it ugly?’ Is not the right question.  The only question is ‘did it get to orbit or not.

[Baker_02]

Quote

I also like to set the tanks flow priority so that fuel is burned from the bottom tanks first, ensuring that my CoM goes up as I burn fuel.

Yes but as I said every rocket I put the cargo on flips to ground between 2 to 5 seconds, which is not enough time to burn almost any fuel.

[Baker_02]

I have a second probe on the rocket and the on on rover is deactivated for the duration of the flight, and hard to tell what is upside down because probe has one position to rover and second to rocket ..... but anyway I deleted the probe on the rover and now the rocket fly as stable as with any other cargo I have. Thank you for help your help

[Baker_02]

 

1 hour ago, FleshJeb said:

You can click on several types of parts and hit "Control from Here", and it will reference the controls to that direction. A few of the probes and command pods have different axes you can pick from, like Up or Forward. This also works with docking ports.

That is a good tip, thanks

[Superfluous J]

Note for future reference, you can launch a ship with the probe core upside down without changing anything so long as you account for that.

Turn SAS on and lock to RETOGRADE, not Prograde. Assuming you use that to assist your gravity turns. If not, it's a bit harder but just remember what you're doing as you manually control the craft.

Mechjeb and other autopilots will probably fail because they don't have brains and just follow code. I don't know about those as I don't use autopilots to launch.