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PTNLemay

My rockets are flipping out... a lot.

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I'm not sure what I'm doing wrong. Have they made the capsules extra heavy or something (making the ship top heavy)? The first stage is okay thanks to ailerons, but once I get to the second stage I start tumbling if I move more than 10 degrees beyond straight up. I can't even perform my gravity turn. This is my rocket: http://i.imgur.com/GrNyeGu.png

I'm also having problems with re-entry. This is the return ship: http://i.imgur.com/Mbj6UzB.png I did my best to keep it perfectly aligned with the drag vector, but before the heat shield could even start to ablate it flipped right over, nose towards the ground, and very quickly exploded.

Can anyone let me know if I'm missing something obvious plz?

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I guess we need a FAQ?

Anyway, you want to launch, get barely off the pad, tilt your rocket a couple of degrees (ie. hardly anything) and then just let it fly. No SAS. No hard pitch overs. If your rocket is stable (and that looks like it should be), it will just fly itself. Keep acceleration at about 2g.

As for re-entry, read the threads on the heat shield problem. Start with just returning the capsule, not a materials lab and storage bay. (Also, if you want to do it the easy way, just stage your chutes before you re-enter the atmosphere. They will pop out and magically stop you.)

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So here's the thing: what was often called a "gravity turn" in old KSP isn't actually a gravity turn at all. In real life (and now KSP 1.0), rockets don't point off of prograde more than a few degrees while in atmo. Or they explode.

A true gravity turn is simply pointing your rocket prograde the whole time (with a slight nudge off of vertical in the beginning to get things started) - as you follow your ballistic trajectory, the rocket will naturally turn as gravity brings it around. Hence "gravity turn". Scott Manley has a nice tutorial video here:

So to summarize - you don't turn a rocket more than 10 degrees off of prograde in real life, and now the Kerbals can't either. Gotta keep the rocket pointing prograde if you don't want to tumble. Makes sense?

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They need to fix the heat shields, though you can by changing it's weight, I can't remember how exactly. Try losing the fins. Also now you start tilting at 5km and reach 45 at around 10km.

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They need to fix the heat shields, though you can by changing it's weight, I can't remember how exactly. Try losing the fins. Also now you start tilting at 5km and reach 45 at around 10km.

This is just wrong.

Keep the fins. Follow the advice Matt and I gave you. See how it works out.

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If it falls over still, try adding more winglets to the base in order to move the center of lift further below the center of mass. As I understand it, the further the CoL from the CoM, the more stable your rocket is, i.e. the stronger the force keeping the rocket aligned with the prograde (direction of motion) vector, but the more difficult it is to turn. With lots of fins you should gravity turn early otherwise the lift/drag forces will prevent you from turning at all.

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I'm not sure what I'm doing wrong. Have they made the capsules extra heavy or something (making the ship top heavy)? The first stage is okay thanks to ailerons, but once I get to the second stage I start tumbling if I move more than 10 degrees beyond straight up. I can't even perform my gravity turn. This is my rocket: http://i.imgur.com/GrNyeGu.png

A lot of people are really enthused about the "actual gravity turn" concept of just turning off SAS and letting the turn go naturally. That's great for people who want to figure out the proper balance, but it's not necessary. You DO need to make slower, more gradual turns now, but there's no reason at all that ship you have there couldn't fly just fine. Though I do highly recommend using a "swivel" or ... whatever they renamed the 909 to for that second stage. Or slap a small reaction wheel into that service compartment.

I'm also having problems with re-entry. This is the return ship: http://i.imgur.com/Mbj6UzB.png I did my best to keep it perfectly aligned with the drag vector, but before the heat shield could even start to ablate it flipped right over, nose towards the ground, and very quickly exploded.

First, know that heat shields are currently bugged, but it's an easy bug to fix. It's three lines of config that need to be changed (and will be in the next update), and easily done yourself in the meantime.

Open your game directory to <path>\Kerbal Space Program\GameData\Squad\Parts\Aero\HeatShield. There, you'll see HeatShield1.cfg Heatshield2.cfg and HeatShield3.cfg. Open each of them in notepad (or your text editor of choice) and look for "PhysicsSignificance = 1". Change that 1 to a 0. Save and close. Repeat twice... you're done.

Second... is a bit more complicated. You have a logical arrangement of parts, but not a balanced one. The material science bay is a LOT lighter than the capsule, so it will act almost like a set of fins on the back, pulling that end around. Fixing the heat shield configs will help with this somewhat, since the shield will have mass again, but you'll still have to fight to keep it pointed the right way. Currently, the best solutions are either a) get EVA capability and just store your science in the capsule, and don't return the materials bay at all... or B) flip physics the middle finger and pop your parachute at 25km in the air, streaming fire all the way. A blast of plasma that will disintegrate a packed parachute does nothing to it once you deploy it, and it'll keep you pointed the right way as an added bonus.

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Thanks for all of the advice, I did manage a return eventually. It works, it's just a LOT more finicky than I thought it would be.

I still mostly end up flying straight up and then completely circularizing once I'm out of the atmosphere, because starting any proper turns in atmo have a 50/50 chance of ending in death spirals. It's embarrassing, I have nearly 400 hours logged in the game and I feel like a noob again, lol.

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Thanks for all of the advice, I did manage a return eventually. It works, it's just a LOT more finicky than I thought it would be.

I still mostly end up flying straight up and then completely circularizing once I'm out of the atmosphere, because starting any proper turns in atmo have a 50/50 chance of ending in death spirals. It's embarrassing, I have nearly 400 hours logged in the game and I feel like a noob again, lol.

The more you learned how the old physics worked, the more you have to forget in order to play the new physics.

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I'm just glad I started playing FAR about six months ago. I had time to get used to the whole "flippy rocket" concept before a similar issue showed up in stock.

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I still mostly end up flying straight up and then completely circularizing once I'm out of the atmosphere, because starting any proper turns in atmo have a 50/50 chance of ending in death spirals.

You're probably going too fast. Try adjusting the thrust of that SRB until it just barely lifts off the pad.

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One issue I find is that the gimbal controls are very jerky, and if you overturn it can be impossible to stop the rocket from falling over unless you have huge amounts of control authority (which exacerbates the jerkiness). This is made worse if you don't strut your craft to the gills to prevent it flopping around. I think the only real solution is to improve SAS to make it smoother; currently it is pretty much useless as you always seem to end up fighting it, and it always seems to overcorrect.

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First, know that heat shields are currently bugged, but it's an easy bug to fix. It's three lines of config that need to be changed (and will be in the next update), and easily done yourself in the meantime.

Open your game directory to <path>\Kerbal Space Program\GameData\Squad\Parts\Aero\HeatShield. There, you'll see HeatShield1.cfg Heatshield2.cfg and HeatShield3.cfg. Open each of them in notepad (or your text editor of choice) and look for "PhysicsSignificance = 1". Change that 1 to a 0. Save and close. Repeat twice... you're done.

I just realized, this is a considerable bug because...

1) A lot of new players will have just started playing the game, on account of the whole "waiting until 1.0 came out before playing" bit.

2) Many of them won't know how to spot these bugs, much less how to fix them with part-file editing.

3) Heat shields are really important, even early on in the game. As soon as you accomplish your first orbit you implicitly require a heat shield.

I would have expected them to hot-fix a bug like that ASAP. We don't want new players getting scared off by bugs that make flying nonsensical. I mean... the ships do still fly, even with an imbalanced shield. So it might not be such a big deal. Still, I hope it's not bothering too many players.

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Even using stock craft I can't get it above a kilometer. I tried using the advice earlier in this thread and it still inevitably flips on me no matter what

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I would have expected them to hot-fix a bug like that ASAP. We don't want new players getting scared off by bugs that make flying nonsensical. I mean... the ships do still fly, even with an imbalanced shield. So it might not be such a big deal. Still, I hope it's not bothering too many players.

They are. Look at the announcements, they're already hard at work on 1.0.1

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