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jimmymcgoochie

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    Kerbonaut Biographer
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    Astronaut Complex rehabilitation centre

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  1. This might be useful in future. Ignore the KSP v1.4 at the top, the values are the same in 1.12.
  2. Travelling directly against gravity uses 9.81m/s of delta-V for each second you're doing it, just to have a net zero change in velocity. Travelling perpendicular to gravity uses 0m/s of delta-V per second to counter gravity. Atmospheric drag in the upper atmosphere is more of a suggestion than something that actually makes a difference to a rocket launch. On Earth, it's just not worth trying to launch straight up; on Kerbin, the penalties are much lower and escape velocity can be reached much faster so it's not nearly so clear-cut. I saw someone saying something about direct ascent trajectories earlier- launching to the Moon without stopping in Earth orbit, or launching from the Moon back to Earth without orbiting the Moon first. Launching straight up from the Moon to return to Earth is possible and I've done it myself in RSS/RP-1, and it makes sense because the Moon has low gravity and is tidally locked so landing on the trailing side guarantees you can launch straight up and get a return trajectory (it also allows for unguided stages, saving mass on all prior stages). Launching from the Earth to the Moon without "orbiting", however, isn't a shoot-straight-up thing: the Soviet Union didn't have a restartable upper stage rocket engine at that time and so had to send their Luna probes straight at the Moon without stopping in Earth orbit first. The US did have a restartable upper stage engine- Agena B- and so could stop in low Earth orbit before performing a lunar transfer burn.
  3. Vertical launch to escape velocity is a bad idea, for several reasons: Gravity. Every second you’re ascending vertically, you lose 9.81m/s of delta-V just not-falling. Real rockets pitch over as soon as they can to minimise this gravity loss and gain horizontal velocity towards orbit. Drag. A high-TWR rocket will encounter significant drag very quickly in the atmosphere, losing even more delta-V in the process. The structural and thermal stresses would also be much greater, requiring a sturdier rocket that can handle those stresses, which adds more weight. Mass. Higher TWR requires more thrust, which adds more weight, which reduces delta-V, which requires more fuel, which adds more weight, etc. etc. It’s a vicious cycle and not easily broken. Scale. Earth is ten times the radius of Kerbin, its atmosphere twice the height, escape velocity more than triple and density substantially lower meaning gravity decreases much more slowly. Launching straight up on Earth would be hideously wasteful. Sol system is inclined, no two planets are in the same orbital plane. Most launch sites are nowhere near the equator either, plus Earth has a significant axial tilt. It’s incredibly unlikely that shooting straight up would actually result in a trajectory that went anywhere near another planet, whereas launching into a parking orbit can allow a departure burn from any launch site, and once per orbit (1.5-2 hours) rather than once per day.
  4. You’re trying too hard with all those different engines. Try swapping the Rapiers for Whiplashes and the Vector for a cluster of four NERVs, which will keep your fuel situation much more manageable as they both only need fuel and not oxidiser. If that isn’t enough to climb out of the atmosphere, a couple of SRBs slung under the wings or a pair of Swivels directly under your tailfins might give it the necessary kick. Ditch the big monopropellant tank and the docking port- that thing is too big to try and dock it efficiently- and then open the CoM and CoL markers and gradually drain fuel from the tanks to see if they shift to an unstable position as the tanks empty.
  5. Watch out for those dust storms, they can get much worse very quickly and you wouldn’t want to end up aborting the mission early and stranding one of your crew, leaving then no choice but to farm potatoes in their own sewage to survive until the rescue mission gets there…
  6. Do you have a controller or joystick plugged into your PC? Phantom control inputs are often due to that so if you do, unplug it and see if the issue persists.
  7. Landing with an atmosphere might be easier, depending on if it’s thick enough to actually slow you down or just thick enough to be annoying. It’s the getting back where an atmosphere becomes a problem. It could also be a hindrance for those crater-skimming flyby passes for gravity assists.
  8. I was thinking the same thing. I know JNSQ Tylo has an atmosphere but adding one to stock Tylo would make it even more of a nightmare challenge to visit with a crewed mission.
  9. Option 4, use the object thrower to destroy them. It’s a bit fiddly to use but also quite fun to use on the KSC…
  10. You’re misunderstanding what direct and relay antennae do. They are calculated separately by the game so a powerful direct antenna with a weak relay antenna won’t help you. A direct antenna can only provide a signal for the vessel it’s attached to. To relay a signal from Jool you’d need an RA-100 relay antenna on the orbiter.
  11. One week’s worth of puddings from the VAB canteen says it falls over due to landing leg overstress within a munth.
  12. This may be a bit off the original topic, but… Can ships be tracked through hyperspace or not? A great deal is made of such a thing being impossible in Ep. 8 and the whole Rose/Finn story is about disabling the MacGuffin that makes it possible, yet in Ep. 7 the First Order are able to track a single X-wing doing recon of Starkiller Base back to the resistance’s base without such a device and in Rogue 1 > Ep. 4 Vader’s ship manages to track Leia’s from Scarif to Tattooine- when logically it would have gone back to Alderaan instead- without any apparent effort.
  13. TestFlight: Engine failure on -X
  14. Comic sans, no matter how obnoxiously large, is still a speck on the scale of the Milky Way. @dsplaisted wins. Rock-paper-scissors-shoot, anything you want to do!
  15. The X-20 was meant to be launched on a rocket with really big fins on the bottom to keep it stable, see link below to the image because I can’t get it to embed right now. https://images.app.goo.gl/m5GNPFeA6QbXE3wU8 Build a normal rocket that has the required delta-V to reach orbit, add an extra 10-20% margin to account for the higher drag and then stick some wing panels to the bottom - no need for control surfaces, engine gimbal and passive stability should be enough. You could also disable the control surfaces on the X-20 itself during the launch as they’ll probably do more harm than good and destabilise the rocket. And if you haven’t already, enable advanced tweakables in the main menu settings and autostrut everything to stop it wobbling itself to pieces.
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