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[TheProphet]

Hi I'm a new player and I need help, I'm currently constructing a large space station, I have the core part in orbit and I'm trying to lift a solar array up to orbit. I've got a lifter which uses 1 orange tank with mainsail booster, 6 of the same surrounding it in an asparagus formation, with the biggest SRBs attached on the outside. It accelerates nicely up to 10,000 ish when I drop the SRBs and then it slowly starts to roll over in random directions and flips out of control. I don't understand why. Please help or can anyone help me with a more reliable lifter 

[Starhawk]

Hello TheProphet and welcome to the forum!

I recommend that you take a look around the Gameplay Questions section of the forum.  If you don't see anything that helps you, then feel free to start a thread there to ask your question.
That's where all the most helpful folk will spot it and respond.

Also, if you do start a thread there, please include a picture of your craft.  This is necessary for people to help diagnose the exact nature of the problem.

Happy landings!

[Ten Key]

2 hours ago, TheProphet said:

It accelerates nicely up to 10,000 ish when I drop the SRBs and then it slowly starts to roll over in random directions and flips out of control. I don't understand why. Please help or can anyone help me with a more reliable lifter 

I had a rocket that did that. Without seeing yours I can only guess, but it sounds like a drag force problem.

There is drag at the top of your rocket, and drag at the bottom. The drag at the top of your rocket makes it want to flip over-- the drag at the bottom makes it want to fly straight. You can visualize it by thinking of your rocket as a broom, with the bristles representing the payload at the top. Drag force can be approximated by adding weights to the broom at the top and the bottom with lengths of string. If you pivot the broom around its center of mass, all of the weights will remain pointed straight at the ground. The weights at the top are going to try to force your broom to tip over. . .the more it rotates, the more rotational force is added. The weights at the bottom have the opposite effect. They will try to keep the broom from tipping. 

What was happening to me (and I assume to you as well) was that the attached boosters were adding a significant amount of drag to the bottom of the rocket. I lost that drag when I dropped them, and suddenly the drag at the top of the rocket wasn't balanced, and it gradually overwhelmed the rocket's steering ability (or "control authority"). 

The solutions are to add more drag to the bottom of the rocket, reduce the drag at the top, add more control authority (reaction wheels, RCS, winglets, whatever) or just slow down a little bit. Drag is especially nasty right as you approach terminal velocity (the mach effects on the rocket are a clue) so if you're shedding your boosters right as you're breaking the sound barrier, that's probably a big part of the problem. 

Let us know any if that helps or not, and if it doesn't a picture of your rocket would help enormously. Welcome to the forums.

 

Edited April 5, 2016 by Ten Key

[Deddly]

@TheProphet, hi and welcome!

I think your rocket sounds much too short and stubby. Think about how long real rockets are. Try at least two orange tanks high and not so many surrounding it. I'd also love to see a screenshot of your rocket.

[max_creative]

More fins, vernors, SAS, and go faster are my ideas. More fins, vernors, and SAS will always work, faster might not.