Jump to content

Lt_Duckweed

Members
  • Posts

    169
  • Joined

  • Last visited

Reputation

234 Excellent

3 Followers

Recent Profile Visitors

The recent visitors block is disabled and is not being shown to other users.

  1. Kerbol space low is actually at 1 million km, not one thousand. With perfectly ordinary heatshields and radiators, you can get to about 200,000 km. You can go progressively lower with more and more esoteric heating exploits and get as close as the edge of the atmosphere itself (600km)
  2. If you look carefully in your screenshot, it says in the top middle of the screen "physics easing in progress". This means the crat does not weigh the full amount, as it was trying to ease the physics as you landed, but presumably you never touched the ground.
  3. You have plenty of lift. Your issue is that your Center of Lift is very very far from your Center of Mass. This means the plane wants to nose down very strongly, and you do not have enough control authority to bring the nose back up. You need your wings farther forwards, and/or larger pitch control surfaces, and/or pitch control surfaces that are farther from the Center of Mass.
  4. Even for stock LKO, liquid fuel only Rapier-Nerv spaceplane SSTOs enjoy a performance advantage over pure Rapier LFO SSTOs. As you go upwards in scale, they lose performance at a much slower pace as well, due to the much higher ISP. The end result is that the hit to performance going to JNSQ is not as harsh as many assume. Of course, special attention needs to be paid to the harsher ascent and entry heat (especially on ascent, as ascent is lift supported nearly the entire way to orbit), but this is ultimately manageable via smart design, and payload fractions near 30% should be achievable.
  5. They are much more difficult, but by no means impossible, and can still be very effective and carry payloads to orbit, and go interplanetary. However, JNSQ SSTOs are much less forgiving. I would describe SSTO building as following an curve with skill that has a very sharp inflection point. That is, for a very long time, even as you get better at making sstos the overall quality of your craft doesn't get that much better, but once you hit a certain point, it explodes very rapidly. For usable stock scale SSTOs you don't have to have found your way past the inflection point. For JNSQ SSTOs you do. In other words, for a very long time JNSQ SSTOs just don't really work, and then suddenly at a certain skill level they work just fine.
  6. Been a while since I fooled with Eve, and since then the devs nerfed the mass of the mk3 crew module, so I figured it was time to take another look at it and redesign my old gross Eve crew SSTO: Into a new, sleeker craft
  7. We do actually have examples in real life of extremely large, volatile poor superearths. https://en.wikipedia.org/wiki/Mega-Earth. Kepler-10c was originally thought to be one before its radius and mass were more accurately measured, but there are a few other examples with more rigidly constrained masses and radii. To be fair though, these usually orbit their stars in very tight, hot orbits that drive away volatiles.
  8. FYI you can't actually cheese reentry/ascent with radiators anyways. Anytime the external plasma temperature (note this is not the same as the current part skin temp, which will be significantly lower) exceeds the radiators max temp, the radiators are hard-coded to shut down. The end result is that by the time you would want them to be helping cool the ship, they are shut down, and rather than radiating heat away they are absorbing heat. And also making lots of drag.
  9. This will NOT work for higher speed reentries. This only works for relatively low drag craft on low speed entries, where the limiting factor over a long entry is the internal temperature of a weak part getting too high due to heat bleed. For high speed entries (well over 3000) you are instead limited by the maximum skin temperature of the weakest part. Often this entirely prevents you from dipping bellow 40km, as any lower and your craft turns into a meteor shower as parts instantly turn into flashpaper. For these types of entries you are forced to stay high, and need to generate as much drag as possible using an extremely high AoA. If my ssto design can't sustain at least 40 AoA from entry through to sub Mach 3, I redesign it. As an example, on a recent mission I hit atmosphere at 4300 m/s. Any lower than 44km and the craft burns up due to exceeding skin temp, so it has to scrub over 1000 m/s in a single pass at 44km at 90 degree AoA. As a matter of fact, I have NEVER had a craft that dealt with problems with internal overheating on reentry. The only time I have ever had an issue with that was with a craft that needed to do an extended hypersonic glide halfway around Kerbin post reentry, and one of the science parts (1200 internal temp max) got close to blowing up. TL:DR - A properly designed spaceplane is going to be able to generate enough drag that it can scrub speed fast enough for skin temp to always be the limiting factor, not internal temp.
  10. Please reread my post. I said an elliptical orbit BELLOW your current circular orbit. Moho is in an elliptical orbit BELLOW your current solar orbit when coming in from Eve. The most efficient way to reach it is to lower pe to match near Moho Pe while also matching planes in the same burn. Since Eve-Moho Dn is quite close to Moho Pe, you want to do your Eve assist at Eve-Moho An. Off the top of my head, to properly match planes and lower pe takes 2 assists because relative velocity to Eve is too high to do it all at once.
  11. This isn't actually true. A normal rendezvous/transfer has the same properties as this Moho transfer. When transferring to an elliptical orbit that is bellow your starting orbit, starting from a (mostly) circular orbit, you need to: Drop your Pe to touch the target orbit. At your Pe, reduce speed enough to match the rest of the orbit. When you do this via transferring to target Ap you essentially: 1. Hohmann transfer to target Ap. 2. Circularize at target Ap. 3. Perform the Pe lowering of another Hohmann transfer to lower your pe to match target pe. When you transfer to target pe you: 1. Perform a Hohmann transfer to target Pe. 2. Abort the circularization burn at Pe partway through, when the Aps match. Perhaps after work I can work out the math on this to provide a proof. Edit: another way to think about it, when transferring to an elliptical orbit, you want to match your Pe vs its Pe, or your Ap vs it Ap
  12. When descending to the surface from a low orbit, you should not be doing a pure retrograde hold descent (aka a suicide burn). Instead, you burn at an angle between retrograde and vertical, so that retrograde is always pointing directly at the horizon (ie, near 0 vertical speed) and only let the craft start to descend when you are nearing the end of the burn and are approaching your landing site. This is called a constant altitude descent. Ideally you start it at the lowest possible altitude that does not result in you smashing into the terrain surrounding your target landing site, and come screaming in just above the hilltops. Done correctly, this actually uses even less fuel than a suicide burn.
  13. You can push off water with a propellor. Its called a boat.
  14. It is due to the drop in the speed of sound. The temp difference is enough to cause this issue. Remember, your total blade apparent speed is a vector sum of the craft forward motion, and the blade rotational motion. To decrease blade apparent speed by, say, 20 m/s (the approx drop in speed of sound going from 4km at the equator to 4km at lat 60) requires 1 of 2 things: A decrease in forward velocity of greater than 20 m/s. (Your case) Or, A decrease in forward velocity of 20 m/s and a reduction in blade rotational speed via reduced rpm. Basically, as speed of sound changes, ideal blade rpm must change. Which is why at high altitudes on Duna for example, you get better performance running your blades in the mid 300's rather than 460 rpm.
  15. Today, I flew into the Sun: The exact techniques and exploits used for something like this are a bit complicated to explain, but I have a couple tutorial/explanation videos in the pipeline that will cover them, among other things.
×
×
  • Create New...