problem with spaggetty flying

[g.koster]

does anyone else has real problems with spaghetti flying. I mean my rocket are behaving if they are hold to gather with rubber bands. in about 10 fuel tanks I have the structure bands ad least 5 degrees.

it is because of this I have real problem flying the some 50 part rockets. I thought that they had fixed this. but it looks like I'm still depending on "kerbal joint reinforcement"

don't get me wrong I like the new update and I'm playing a 10% game. so upgrading to higher science is not easily done. So a bid creasy structure building is in the game.

[r4pt0r]

I presume you have 10 of the small tanks stacked? changing those to 3 bigger tanks would save you so much trouble.

[ShawnPhillips]

STRUTS!

But seriously, The new areo in 1.0 places most of the drag force on the nose of your rocket then the lower sections. With the drag pushing down on top and the engines pushing up on the bottom it is squeezing your rocket causing the bending. some struts connecting the weaker joints should help.

[sal_vager]

The most wobbly parts for me seem to be the stack decouplers, tanks seem pretty rigid.

Higher gimbal doesn't help, you can dial it back though.

[Geschosskopf]

Struts really do help a lot with flexing rockets. What you need to do is run struts from as far below to as far above the weak areas, so the 1st step is to identify the weak spots and remove those you can by design.

To me, the main wobbly areas are as follows:

* Radial decouplers tipping inwards are the top when their rockets are firing. Solved with 1 strut between the top of the radial booster and the core.

* Docking ports in the core stack. For me, this is the worst source of wobble. Using docking ports the same diameter as the stack helps a lot but even this has its limits in 1.+, somewhat more wobbly than previously. Really long payloads forward of the docking port still flex, so the best solution is to run struts from a larger adaptor below the port to the part above, or put some outrigger beams near the port and run struts from the outboard ends of these to areas well above and below the port.

* Really big fairings compared to the diameter of the stack below. In general, if you need a huge fairing, like for a big rover, use the largest diameter part you have available so the rest of the rocket is also as wide as possible. And run struts through the fairing from the rocket below to the payload within.

[Blu_C]

You can attach struts to decouplers too. Really when it comes to a craft wobbling there are a few things you can do:

1- Disable some/all of your engine gimbles. This is usually a good choice if you have a lot of gimbling engines firing at once. I try to keep the number of gimbling engines to a minimum as much as possible. On a similar note you may want to opt for fins instead of winglets.

2- Struts. These can add a lot of strength, and can be especially helpful early on in the thickest part of the atmosphere. I suggest strutting out radial stages to higher up on your craft, this will make it significantly more rigid. You can also strut your radial stages to eachother for added strength.

3- Turn off SAS. This can be a pain, especially during launches, but SAS tends to be very twitchy and in large or long things will set up oscelations. Usually this is a good option if you are already in space.

[EtherDragon]

Spaghetti flying is a result of too many torque forces acting on too many different places all at once. This usually occurs when you have more than one torque wheel, or a torque wheel and gimbaled engines enabled at the same time.

Generally, if I'm using a torque wheel (either what's in the cockpit or a separate one) then I make sure that there is only one for control.

[Geschosskopf]

Spaghetti flying is a result of too many torque forces acting on too many different places all at once. This usually occurs when you have more than one torque wheel, or a torque wheel and gimbaled engines enabled at the same time.

I disagree. I routinely load my rockets down with SAS modules on each stage---more torque = more control and generally less wobbliness. You have to ask, why is the rocket wobbly? The root cause is because some external force (caused by a combination of thrust and aerodynamics) is acting on it, to which the various control systems in the rocket (SAS, RCS, and tail fins) attempt to counter. If the rocket is structurally weak, then it will flex under both the applied loads and the efforts of the control systems to stay on course. This usually causes the wobble to get worse because the control systems are assuming the rocket is rigid. OTOH, if the rocket is structurally sound and still wobbles, it's because you don't have enough control authority to counter fully the applied loads. So, build a rigid rocket with beaucoup control authority and you'll be wobble-free.

[g.koster]

larger tanks are at the moment still 12 points away, and struts a 57 points. and yes if I had them I would use them. The structure itself is bending already on the platform, once I had it dancing.

It could well be that SAS as the structure has 10 pods is not helping when the bending forces are during launche the other way round. But the basic platform is only five in diameter and that is already bending on the platform. as the first stage is solid boosters there in no gimble.

And a same kind of structure is completely stable with "kerbal joint reinforcement"

[Geschosskopf]

Dancing on the launchpad? I had that happen once. It turned out to be caused by me putting the probe core inside a service bay and hangning it from the ceiling instead of putting it on the floor. Moving the probe core to the floor of the service bay solved this problem.

[g.koster]

No Iits not a service bay, I'm not further then engeniering 101 and basic rocktry. so the first tree siences.

[ColKlonk]

I disagree. I routinely load my rockets down with SAS modules on each stage---more torque = more control and generally less wobbliness.

You'll still get the wobbles, but it's naturally worse if the wheels are not centrally aligned.

Enabling RCS thrusters at the same time is a good indicator... watch your ship try twist itself apart..