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Everything posted by camacju

  1. Latitude -25, longitude -158.5 Pretty sure this is the tallest mountain on Eve and it's got a nice smooth takeoff area
  2. It's actually a lot easier to skip Gilly entirely and just go direct, you'll use more fuel slowing down to land than just continuing your escape burn. There are a few different ways to do it. Since this challenge requires no propellers, I would suggest starting with one of Astrobond's designs: From there you can tweak ascent profile, wing area, and thrust-to-weight ratio. Try to get as much payload in orbit as you can. Another thing to try is to assist the ascent with nuclear engines. If you fill the wing tanks with liquid fuel, you can have zero additional dry mass (besides the engine), which is nice.
  3. One fairing is the entire fuselage of the craft. Fuel tanks are clipped inside the fairing along with the vector engine. The blue stripes up front is an ISRU module because I was trying to do a full self contained mission at the time. The fairing is the root part of the craft so drag is reduced but this is probably not strictly necessary.
  4. Ok, I'm not sure if this is a good topic for this forum because it might or might not be possible. I was playing around with some Eve SSTO designs and got this: This craft uses a single Vector engine for the ascent - no propellers. It actually has enough payload capacity to fit in some ion propulsion and go all the way back to Kerbin. This alone is nothing new - Brad Whistance did it years ago. But this is a much lighter design and has a greater payload fraction, which leaves another possibility. The main question I have is: Is it possible to go from Eve's surface to Kerbin's surface in a single stage, with no propellers and no ion engines? I've done some calculations and it seems like it may be possible, especially if the craft is scaled up and a Mammoth engine is used instead of four Vectors. I know that it's possible to go from Eve to Kerbin with propellers and no ion engines, but propellers definitely make the challenge easier. I think this will push right up against the limit of what's possible on a purely rocket-powered Eve plane. More detailed rules: -The craft should be able to start on the surface of Eve (stationary) and end up stationary on the surface of Kerbin. -No staging (also: no docking with or clawing anything, no burning off parts or removing them through EVA construction) -No ion engines (because we already know that's possible) -No propellers (Stock props should already be disallowed through the no staging rule, so just don't use any parts from the Breaking Ground dlc. If there are any loopholes they will be patched) -ISRU optional (you can edit the craft to Eve's surface if you want) but if you manage to take a set of ISRU equipment as well then I will be impressed.
  5. Yeah, I got the idea from Ultimate Steve's grand tour. It's a bit annoying to take off successfully because of seams in the terrain but it's a lot lighter than normal landing gear.
  6. you could use a Big-S wing and control the craft just through gimbal and reaction wheel, that would save 5 parts or so. Also maybe remove the battery and just use the cockpit internal battery?
  7. Update: I finished the mission a while ago with 332 liquid fuel remaining. I haven't gotten around to editing the video yet.
  8. Haven't quite finished my attempt yet. I'll post some teaser images I guess
  9. ooh I've got some ideas for this one. Will take a crack at it when I get home!
  10. I'm actually not using the dragless fairing trick here. The air intakes are attached to the front of the fairing and offset backward, partially occluding the front drag cube face (the rest is done with fuel tanks attached to the interstage nodes, which is still a little exploity but certainly not on the level of eliminating all drag). This was to save the mass of an engine plate. I offset the air intakes backward to balance out the body lift of the fairing base, otherwise the craft would become very unstable around Mach 2. They produce the same amount of drag either way. (The fairing base is at the front so I can drop the jet engine out the back and avoid a lot of funny stuff with colliders). The Laythe lander is partially empty of fuel to save mass. As a result, it's very light, and has a lot of drag because a fairing was too heavy to be worthwhile. Also, I take a shallow aerobrake trajectory and angle the lander so the basic fins can provide lift. Note how reentry effects don't even show up on descent, because I slow down so much in the upper atmosphere that heating is never an issue. The problem with aerodynamic exploits is that they usually require additional parts, and the extra mass just isn't worth it for this mission.
  11. Yet another Jool 5, this time optimized for low mass.
  12. very impressive mission however physics exploits are not allowed
  13. This was a fun challenge! It's my first time in RSS and I don't really know of the RSS-specific optimizations, but I think this did pretty well. Piccard III on the runway (Piccard I had issues with asymmetric thrust under high time warp and Piccard II didn't have enough wing area) Climbing to altitude Settled down at Mach 0.6 and 2 degrees angle of attack. This is close to optimal for subsonic range with the Goliath engine, and this craft is designed to fly subsonic so I can get it off the runway more easily. Supercruising with the Goliath gives more range, but it would be much harder to take off and I would run into heating issues. Gallery: Final descent. I have no roll control here so I can't land on the runway, but I can still land on the grass. Landed! If I were to attempt this mission again, which I won't, I would probably remove some air intakes as they were a pretty big fraction of my total drag. I would also add ailerons. A couple smaller optimizations would be to use the Mk0 fuel tank instead of Mk1 fuel tanks and the Big-S strake instead of the delta wing, which would reduce my dry mass. I didn't do this for part count reasons, but they would be reasonable upgrades with a more powerful computer than my laptop. A large optimization would be to reduce wing area and switch to supersonic air intakes (maybe a single shock cone or ram air intake would work). Cruise would be at Mach 2 instead of Mach 0.6 - this would increase the value of speed * lift / drag, which dictates how far you can fly on a given engine and amount of fuel. You'd need a really long takeoff run to make full use of this, and I'm told there aren't a lot of large flat areas on Earth to act as a runway. But this flight is definitely beatable.
  14. Looks a lot like this challenge! For this one, I submitted a pair of Kerbals in quite the situation. -Retrograde Kerbol orbit -periapsis 4921 km -apoapsis 536000 km They are in a very heat resistant vessel so that shouldn't be an issue. I can DM you the save file if you want.
  15. This is an interesting challenge. I was going to try to cheese it - the DLC turboshaft engine has a built-in alternator that scales with RPM and not with torque, and is also frictionless. Kickstart it and it provides electricity forever, like a less mass efficient RTG. My plan was to run one unit of liquid fuel through the turboshaft to charge a small battery, and then spin it with some DLC electric motors to generate electricity more. Time warp wouldn't be an issue as I could just start it from the battery again, and then I would do something interesting like a Jool surface return using ions and magic wings. However, what I discovered as I was testing crafts was that for some reason, the alternator would scale with 1/(rpm limit). I assume this was to simulate the effect of a gearbox, even though it would be perfectly backdrive-able. Apparently, when rpm limit is set to zero, alternator output hits a divide by zero and evaluates to infinity, which basically means that I've discovered an infinite electricity glitch. A clip of it is attached below. Note the change in electricity generation when I change the motor's RPM limit, and how I generate 64k electric charge in a single frame when RPM limit hits zero. Also, I'm spinning the turboshaft at 920 RPM by rotating both the base and the rotor with DLC electric motors, because I planned to do this originally to generate twice as much electricity per motor.
  16. Discord is best for small communities in my opinion. I find it a lot easier to keep up with, for example, super-optimized stock KSP missions, because there's a pretty small group of people who actually does that and it kinda gets lost in this big of a forum.
  17. It doesn't need to be exploity. You can do something like attaching a 1.25 meter fuel tank to the front of the fairing, or a 1.25 meter nose cone. It'll occlude just as well.
  18. It's a Mechjeb unit because I'm not good enough of a pilot to fly this craft consistently - the ascent profile needs to be very precise with a lander this small. It doesn't really provide a benefit to the craft otherwise, in fact it just adds drag, but it's a good band-aid solution for my lack of piloting skill. I also use Mechjeb for aero and TWR info in a nice compact display, so it's not just used as an autopilot. Edit: The ascent profile is roughly as follows: -Go up to 43.5 km altitude on propellers. The propeller stage can go higher than this but it takes a really long time. -Light all engines and pitch down to 55 degrees pitch. I found that this was a good angle to get out of most of the atmosphere and also build up vertical speed. If drag weren't an issue, I would want to go closer to 30 degrees, but drag is an issue so I want to get out of the atmosphere quickly. -Drop fuel tanks as they empty. I don't draw fuel from upper stages as the engine dry mass isn't worth it. -When apoapsis reaches 65 km, lock prograde because there's enough vertical speed from the second stage. -When the second stage detaches, pitch to 30 degrees and hold it - the Spider engine has really low TWR so this is necessary. -Finally, circularize with the jetpack. I hold the translate forward and upward keys at the same time, which loses a bit of efficiency but buys time to gain horizontal speed. This is important because the jetpack also has very low TWR, so it needs a lot of centripetal force in order to maintain altitude.
  19. Motivation For a long time, I've been interested in ultra low mass missions, and even flown a few myself. It's incredibly satisfying to iterate on a design and watch it get smaller and smaller, often beyond what I believed was possible originally. One of the most difficult challenges in stock KSP is getting a Kerbal from Eve's surface to a low Eve orbit. The high gravity, dense and unoxygenated atmosphere, and large planetary size all combine to make Eve more difficult than any other planet (with the possible exception of Jool, which doesn't really have a surface). Low mass Eve missions are very interesting - Bradley Whistance's 9 ton Eve mission was a big influence in how I play KSP. The Design Process At the beginning, I stuck to a few design principles common in low mass craft: -The craft would be controlled through a command seat. The command chair is much lighter than any command pod - not only does this reduce mass of the craft directly, it also requires less propellant to launch into orbit. However, it's not very aerodynamic, which is a bad thing when dealing with Eve's atmosphere. Fortunately, a command chair in a fairing is still much lighter than a command pod, plus the fairing can shield fuel tanks and engines from drag. So I also decided to use a fairing on the lander. -I would use a propeller to get above the majority of the atmosphere. Not only does the atmosphere present issues with drag, it also reduces the efficiency of my engines. With a propeller, not only do I incur less drag, I also start burning the rocket engines from a higher altitude (meaning I have more energy and thus use less delta-v), and the burn can be done at a higher efficiency. Note that propellers aren't the best for Kerbin because jet engines are lighter and can give a bigger speed boost, but jet engines don't work on Eve. -I also want to use the EVA pack to finish circularization. The EVA pack with the extra fuel cylinder is about 900 m/s of delta-v, which is too much to pass up and more than makes up for the additional EVA propellant mass by lowering the fuel requirement. I've divided the various iterations of the lander design into categories so there isn't a big text wall. The initial lander design is 5 tons and gets improved from there. Category 1: Ducted Fans At this point the mass of the Eve lander is 3.31 tons. This is a huge improvement, but we can do better still. Category 2: Basic Fins Category 3: Basic Fins, Part 2 Category 4: Fairingless The final result
  20. I got a ~10 ton craft functional, but I didn't fly it beyond low Kerbin orbit. @Ultimate Steve If you're still interested, I'd love to collaborate on another grand tour!
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