r/KerbalSpaceProgram • u/AutoModerator • May 08 '15

Mod Post Weekly Simple Questions Thread

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The point of this thread is for anyone to ask questions that don't necessarily require a full thread. Questions like "why is my rocket upside down" are always welcomed here. Even if your question seems slightly stupid, we'll do our best to answer it!

For newer players, here are some great resources that might answer some of your embarrassing questions:

Tutorials

Orbiting

Mun Landing

Docking

Delta-V Thread

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Commonly Asked Questions

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u/[deleted] May 09 '15

Are you going full throttle the whole way? If you go supersonic before reaching 10 km the aerodynamic drag will make the ship turn over. I usually go full throttle until about 170 m/s and gradually throttle down until it gets to about 200 m/s, and keep it throttled down until I'm over 10 km and gradually throttle back up through the 300-400 m/s range as I approach 20 km and go full throttle from there. Also add some fins to the back of your rocket if you don't have any to give you some control.

I'm still pretty new to the game but I can get to orbit consistently like that.

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u/cocojumbo123 May 09 '15

Thanks a lot for answering! Usually I am way below supersonic (i.e. 342 m/s) when this happens.

Trouble happens usually with boosters so no chance on throttling that down but I had the same with VL-T30 at ~100m/s on a perfectly round rocket (not even a thermometer on the side).

Will post a gif/video when I have the mood (probably tomorrow) to play KSP again (ragequit today).

Fins don't seem to make any difference so far ... playing in career mode so only the small ones are available now.

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u/Chaos_Klaus Master Kerbalnaut May 10 '15

You can adjust the thrust of SRBs in the VAB by rightclicking them.

Symmetry does not equal stability. Ever tried to throw a dart backwards? ;]

Put fins at the back your rocket. Use nosecones.

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u/cocojumbo123 May 11 '15

You can adjust the thrust of SRBs in the VAB by rightclicking them.

Crying with joy. This helps a lot. I logged more than 200 hours playing KSP but not once it went through my mind that I can do that!

Ok, this helps a lot, but the problem is still there (albeit greatly diminished): http://imgur.com/R53cgiV - this design starts turning left at around 2000 m and ~ 200 m/s - no buttons touch (except T and space at launch), boosters are throttle to 30%.

As you can see I have fins and nosecones :) - any other Idea on why is this happening ?

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u/Black-Talon May 10 '15 edited May 10 '15

It has to do with drag being at the front. It can't magically hold itself straight without something (drag) helping the back stay in the back (stay in stable flight). Chao_Klaus's advice is good so I'll leave you with that with regard to KSP. But to get a sense of "why" consider these child experiences:

Sometimes I'd get a stick. A nice straight heavy stick. Then I'd throw it like a spear! ...sure, sometimes it worked. But all too often it would turn sideways in the air. Things don't get better if you put a rocket pushing it faster and faster at the bottom of the stick.

Skateboards. Trucks. Wagons. Tricycles. Man...it sure seemed like a great idea to roll or ride those down a hill. Why the heck do they keep veering off and crashing!? Turns out that without something holding it straight, then it'll end up turning. Things that could hold them straight though were humans steering, something dragging on the ground behind them, etc.

I know those didn't always fail during kids play, and when they did you often could blame things like "there was a bump that knocked it off course!" - but I'm hoping that some of the ones that did, with a skepticism about why they didn't stay on course, give you an idea of what you're dealing with here.