Rockets Can't Leave Atmosphere

[arsenal3185]

When I build a rocket, no matter what configuration (regular, asparagus, fairing, ignorant to aerodynamics), the rocket can get up to the stage where I used to preform my gravity turns (5,000-7,000 meters). As soon as I tilt my rockets even the slightest bit, they flip over. I've tried not even putting a payload on rockets and they all still flip upside down and refuse to point up again. I've tried no payload, limiting the gimbal, limiting the thrust and fuel amounts, etc. The rockets definitely aren't top-heavy, so what's the issue here?

[Kerbart]

2 minutes ago, arsenal3185 said:

When I build a rocket, no matter what configuration (regular, asparagus, fairing, ignorant to aerodynamics), the rocket can get up to the stage where I used to preform my gravity turns (5,000-7,000 meters). As soon as I tilt my rockets even the slightest bit, they flip over. I've tried not even putting a payload on rockets and they all still flip upside down and refuse to point up again. I've tried no payload, limiting the gimbal, limiting the thrust and fuel amounts, etc. The rockets definitely aren't top-heavy, so what's the issue here?

For one, the issue could be that your rockets are not top heavy. A rocket is like a dart; the more forward the center of mass is, the more stable it will be.  The longer the distance between the fins (at the back) and the center of mass, the longer the lever is for aerodynamic forces to provide torque to keep your rocket flying straight.

In short:

• Put fins as far backward as you can
• Try to move the center of mass forward. That doesn't always mean moving stuff forward; it also means limiting heavy stuff (engines) at the bottom.

[NathanKell]

1 hour ago, arsenal3185 said:

 (5,000-7,000 meters).

Yeah, that's your problem.

You should be tipping over gently well before you reach a single kilometer up. And don't give yourself too much thrust, either.

[arsenal3185]

1 hour ago, Kerbart said:

For one, the issue could be that your rockets are not top heavy. A rocket is like a dart; the more forward the center of mass is, the more stable it will be.  The longer the distance between the fins (at the back) and the center of mass, the longer the lever is for aerodynamic forces to provide torque to keep your rocket flying straight.

In short:

• Put fins as far backward as you can
• Try to move the center of mass forward. That doesn't always mean moving stuff forward; it also means limiting heavy stuff (engines) at the bottom.

 

 

32 minutes ago, NathanKell said:

Yeah, that's your problem.

You should be tipping over gently well before you reach a single kilometer up. And don't give yourself too much thrust, either.

Thanks, guys! I'll try tomorrow and maybe come to this thread.