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Snark

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Everything posted by Snark

  1. Moving to Technical Support. (Glad you had a backup!)
  2. The question was asked and answered eight years ago, and presumably everyone involved in the conversation has long since moved on to other things. Accordingly, locking the thread to prevent further confusion. Thank you for your understanding.
  3. No worries, can happen to anyone. Locking thread to prevent any further confusion.
  4. Moving to Add-on Discussions.
  5. Some content has been removed and/or redacted due to personal remarks, off topic digressions, and other problems. Folks, it's fine to disagree with one another, but let's please keep it civil. Name-calling and finger-pointing doesn't win any arguments, and makes the forum a less pleasant place for everyone. Thank you for your understanding.
  6. Fair 'nuff. My own solution to that problem is "never approach a maneuver quickly", i.e. get the ship pointed correctly well in advance.
  7. Moving to Gameplay Questions. Alt+F12 menu -> Cheats -> "Infinite Propellant" checkbox.
  8. Since, as you observe, this is in fact a 9-year-old thread, I think it's safe to assume that everyone involved in the original discussion has long since gotten the problem figured out and moved on to other things. Not to mention that KSP has changed so much in the meantime that any pre-1.0 advice would be very wrong today. Accordingly, locking the thread to prevent further confusion. If anyone has current questions about how to get to orbit, feel free to spin up a new thread. Thank you for your understanding.
  9. This is kind of a digression from your main concern about the gimbal, but... is there a reason you've got your RCS thrusters turned on for attitude control? i.e. there are two ways to control the attitude of a ship in orbit: RCS thrusters, and reaction wheels. Reaction wheels are "free" (just electricity), whereas RCS uses consumable fuel. So, since it's not free... any reason why you're using it? (If you like to have it turned on for realism, then never mind.) RCS thrusters let you configure which actuators are enabled. I like to always set all my RCS thrusters to be enabled for translation only, and have them disabled for pitch / yaw / roll. Saves on monopropellant quite a bit. (Of course, remembering to always turn off the rotation actuators every time I place an RCS thruster in the VAB is a hassle. Fortunately, it's easy to make rotation "off by default" with a simple ModuleManager config patch. Here's config that does that, if you're interested.)
  10. A couple of other points: If you haven't done so already, turn off everything but yaw on the vertical stabilizer. You want it to be helping with yaw only; you need to turn off roll control. Doing this will help with stability, for reasons that I can explain if you're interested in, but it's a long paragraph so I won't bother unless you're interested. Your CoM is pretty far back, which is likely to make the craft want to flip. If you can move the CoM forward-- for example, by sliding the engines forward-- that may help.
  11. Which TWR is "right" depends on a lot of factors, including how you like to fly and what sort of payload you have. In general, you never want to go higher than 2.0, and usually no lower than about 1.2. The optimal rocket design changes quite a lot based on the TWR. If you have a very "draggy" payload (which most of your rockets look to be-- you've got a lot of flat surfaces, these are not very aerodynamic), then usually a lower TWR tends to work better, at least for the first several kilometers of ascent. This is because a high TWR causes you to go too fast when you're still too low, so you're wasting all your fuel trying to shove a draggy thing through thick soupy atmosphere. Taking off a bit more slowly, to keep drag down, may help. (Normally, the solution people go for is to make their craft more aerodynamic and then raise the TWR, which is more fuel efficient. But if you have an awkward payload that has to be draggy, you may have better luck starting off a bit slower.) In general, the most efficient (and stable) ascent path is called a gravity turn (that's a good term to search the forums for, if you'd like to read about it). The basic idea of a gravity turn is that you nudge the craft just a little bit eastward, practically right off the pad... and then you just set SAS to hold all the way up. No steering needed, you're just going all the way, as your ship gradually and naturally pitches farther and farther eastward as it climbs. Just how much of an initial "nudge" you should give it is the tricky part, of course. There's no one right answer, because it depends on your TWR and how aerodynamic you are. But there's a fairly straightforward way to find out: Launch to the pad. Take off! Immediately upon lift-off, pitch a small amount eastwards. (Just take a guess, as to how much.) As soon as you do that, set SAS to hold Don't do any further steering. The only time your hands should touch the controls is to jettison empty stages when the time comes. Take a note of what your trajectory is like when you reach an altitude of 10 kilometers. Specifically, how fast are you going? what angle are you pitched at? Ideally, you should probably be pitched roughly 45 degrees at that point, and traveling something like 300-400 m/s. If (at 10 km) you are going too fast, or pointing too vertically: This means you didn't pitch quite enough in step 3. Revert to launch, and repeat, and pitch it a bit more this time. If (at 10 km) you are going too slow, or pointing too horizontally: This means you pitched too much in step 3. Revert to launch, and repeat, and pitch it a bit less this time. Keep repeating steps 2 through 7 until you're going about the right speed and angle when you're at 10 km. At this point, you're in the pipe and probably going to space, as long as your fuel holds out. The above is only a very rough rule of thumb, but I've found that it works pretty well for most people most of the time, and at least is a pretty good starting point for flying your ship. Really don't do that. Very very fuel inefficient, and will waste scads of dV. That's also very inefficient, and likely to cause control problems, as you have no doubt discovered. The moral of the story is: You want your rocket to be traveling at all times. Never point more than just a couple of degrees off while thrusting, if you can help it.
  12. ^ This. FWIW, I think there's a mod to help with this breakage. This may help?
  13. I'd suggest adding a couple of small canards on the front end. Oversteering's a risk, so make them as small as possible (the advanced canards are good for this, the AV-R8 are kinda big), and set their control authority to about half the default, and set them to be pitch only (they shouldn't be engaged for roll). That ought to give you a bit better pitch control, especially when the CoM moves forward as you burn fuel. Might also help to give it a bit more reaction torque for control. If you add a Mk2 drone core, that has a fair amount of torque built into it. Actually, I would have said it isn't-- on the contrary, looks like it's about in the middle of the plane, maybe a bit too far in the rear for comfort. Farther forward might be safer-- there's some risk of aerodynamic instability with the CoM as far back as this is. Fortunately, it looks like the CoM will move forward as fuel is burned, so that should help.
  14. Can you describe exactly what behavior you're seeing? What do you mean by "flipping like a bullet"? And which part are you talking about, the upper stage? Got a screenshot?
  15. Several posts have been removed and/or redacted, due to off-topic content. Let's please remember that the topic of this thread is this mod, so discussions of player habits (or anything else that's not about this mod) don't really belong here. Thank you for your understanding.
  16. Several posts have been removed, due to an off-topic digression that had nothing to do with this mod. Please try to remember that this thread is about this mod, and discussion unrelated to the mod itself would best go in another thread. Thank you for your understanding.
  17. I'm guessing that you have your CoM up near the top of the vessel. If that's the case, it's going to be very hard to keep it from flipping. We could talk about that, sure, but... out of curiosity, why do you you need to care about flipping? As long as you have a pretty good transfer window and don't come screaming in at many thousands of meters per second, Duna reentry is pretty gentle (just a bit over 1500 m/s). I usually don't even bother with heat shields; I just make sure not to have anything extra-melty (i.e. science instruments) exposed to the blast, and even that's not a problem if I just apply a bit of retro-thrust before hitting atmosphere. So, why not just let it hit atmosphere in whatever orientation it likes? (And save the mass of the big heat shield, in the bargain.)
  18. This is more a discussion than a question about how to play the game... so moving it over to KSP Discussion. Personally, I usually end up rotating the camera all around at different angles depending on context. The navball is my reference for anything actually important (i.e. navigation), so for me the camera view is eye candy, and I therefore tend to rotate it around to whatever gives the most fun or pretty or interesting view in a given situation.
  19. From the last time this question came up: Also,
  20. Professional software engineer, for the last quarter-century or so. (I was a physics major in college, but afterwards ended up finding playing with computers more fun, not to mention more employable.) Oh, and play KSP, of course.
  21. Nope, nothing to do with BBT. Whatever's going on here, it's pure stock behavior. BetterBurnTime hasn't done anything with maneuver node burn times since I released version 1.7 in October 2018, for compatibility with KSP 1.5: (BBT does still do burn calculations... but only for target intercepts and surface landings. It doesn't do maneuver nodes anymore, deferring to KSP's stock behavior.)
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