Grogs

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About Grogs

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  1. Yes, that was an absolute game-changer in the stock game! Trying to grab/drag the maneuver node without pulling on any of the toggles (prograde, etc.) was hard enough for a simple orbital rendevous. Doing it for an interplanetary burn when you were focused on another planet was almost impossible. As for the OP's question, I don't think that there is necessarily any advantage to doing a mid-course burn. Ideally, you'd nail the exact course from Kerbin orbit and the crew could sleep until the injection burn. The problem is that the transfer burn from Kerbin orbit is usually 1000+ m/s. Unless you have a very high TWR, that means you will be burning relatively far from the actual maneuver node for part of it. I might tune the maneuver node to reach Jool at exactly the periapsis I want, execute it perfectly, and still find my course is off a bit. With really small targets it gets even harder because they have so little gravity. I just did a transfer from Eve to Gilly in a game and coming out of Eve orbit a 0.1 m/s difference meant the difference between getting an encounter with a 15-km periapsis and missing the moon altogether. Since I couldn't tune it that precisely, I launched on a 'close enough' trajectory. When I was ~ 80% of the way there, I did a correction burn to get the encounter and it was still only about 2 m/s. It was worth the extra 2 m/s because I just couldn't dial in the intercept precisely enough from the start.
  2. Start with the lander design. Design a ship that can de-orbit, land safely, and reach orbit again. I would try to design a 1-kerbal lander initially. I tried a 3-kerbal design several times and found it to be monumentally more difficult in comparison. What the others say about minimizing drag and mass on ascent is absolutely true. Even something small like a ladder can cost you 100 m/s and make your ship fail to reach orbit. Put chutes, landing legs, ladders, and anything else that sticks out on decouplers and have them detach when you light the first stage of the ascent vehicle. Use the ALT-F12 menu to test your design and see how spectacularly it fails. Go back to the VAB and try again until you have something that works reliably. Once you have a good lander design, you've conquered probably 90% of the major hurdles on the mission and the rest is much easier. The next piece is to figure out what you want to get the crew back to Kerbin orbit with. It may be the upper stage of the Eve ascent vehicle that refuels in orbit or something else that you bring along. Add enough fuel to get you back to Kerbin orbit. With the mass of the lander and the return vehicle, then it's pretty simple to figure out how big of a transfer stage you need to move everything from Kerbin to Eve. And once you have that, figure out how to get it all to orbit. Depending on how big or fragile the whole package is, you might want to break it into multiple pieces and assemble it in orbit. That makes the launches easier, but then means you have to design each piece so that it can maneuver and dock.
  3. Nice. 2001 was before my time, but 2010 was one of the first films I ever saw with a date. I sat there with my mouth open staring at the beautiful scenes of Jupiter the whole time. She never talked to me again after that. I've only had a problem with really big boosters, like S4-64's. I find having the decouplers near the top kicks the top of most boosters out enough that the air will catch it and pull it away from the rocket. The decouplers just don't have enough push to move the big boosters, and especially later in a gravity turn while the rocket is pitched down the top boosters will collide before clearing the engines. I've resorted to attaching sepratron rockets in those instances, and it has worked well, but I can see the struts as being a more elegant solution.
  4. Yeah, I've got autostruts, but like some of the others have said, they're not a panacea that can solve every possible stability problem. My strategy was roughly: - Autostrut the radial boosters/tanks to grandparent. These are rock solid, and I've never had an issue doing this. - For the big S3/S4 center tanks, I autostrutted them to root part. Again, I've never had a problem doing this so long as the direction of the root part never changes. In this case, it's always "up" towards the pointy end of the rocket no matter how I rearrange things above. - For the parts above the fairing, I found they would sway back and forth and clip through the fairing when I maneuvered to do my gravity turn. I tried using grandfather autostruts in that area, especially where there were docking port connections, but I wasn't able to get it stiff enough. I didn't dare use root or heaviest part here, because these do come apart and possibly change orientation. The real struts helped. Since they're inside the fairing, they're just adding a tiny amount of weight and no drag. I decided that was a good trade-off. - The struts on the rover/sky crane were on the original model I borrowed. This model is really just a placeholder until I find something I like better. I didn't look to see if some of them could be eliminated.
  5. I worked on building an expedition rocket. I didn't really have a specific mission in mind. I just felt like building something, and I wanted it to have more dV than something like a standard Duna rocket. First item was the command module. Started with a Mk1-3 command pod, plus a hitchhiker to give the kerbals space for RP reasons, a science module, service module with several experiments inside, and enough liquid fuel to give over 5200 m/s of dV with the Nerv engine. I figure that's enough to get the crew back home from pretty much any other body in the Kerbol system. The only gripe is that the Mk3 to 2.5 m adapter is only available as an lfo version. I emptied out the oxidizer, but I would rather be able to fill the whole thing with lf. The lander is pretty standard. It has about 3300 m/s and enough thrust to land on the Moho, Dres, Duna, Eeloo, and all the moons but Laythe and Tylo. I added chutes to make the Duna landing easier. The chutes would also work for Eve or Laythe, but that trip would be one way. I also took advantage of the door I didn't know existed until recently and crammed in some batteries and monoprop. The docking adapter on the bottom is used to redock on the transfer stage, then the CM docks to the top and the whole package can move to another location. I added a rover with a sky crane for scouting. This is basically the model included with the game, except I added fuel, upgraded the probe core and antennas, and added parachutes. I'm OK with this for now, but I hope to eventually improve it. Actually, I'd like to make a modular lander/rover where I could send down just the lander, just the probe, or both together and have enough dV to return from the same set of bodies. Here are the command module, lander, and rover attached to the transfer stage. Transfer stage gets 2800 m/s from the drop tanks, then another 4574 m/s from the center fuel tank for a total of 7374 m/s dV. That's enough to get from Kerbin to Eve/Gilly, then on to Moho. Another option might be Kerbin to Duna, Dres, and Eeloo. This is the full ship on the pad. Total pad weight is a svelte 5943 tons and the whole thing costs 3.4 million funds. ... and after getting into orbit. I had about 1000 m/s left, so there's room to either increase one of the upper stages a bit or reduce the boosters.
  6. I feel largely the same. I don't run any life support mods, but I do include a good bit of extra space for role-playing purposes. For trips to Mun or Minimus, I'm OK with 1 seat / kerbal, but for longer missions I would want at least 2, or maybe 3 seats each. For my Jool-5, I took a crew of 9 even though the level 3 mission only requires 5. I put a Mk3 cockpit and two 16-kerbal Mk3 passenger modules on the mother ship, which gave 4 seats per crew member. I figure that's enough space for the ship to have sleep cubicles, a small kitchen, acceleration chairs, etc. There were also 4 other Mk2 or Mk1-3 pods between the landers, so I figured that gave them space to go get away for a while if needed. I only use command chairs for surface landers on low-G worlds.
  7. I finished up the last of the MH missions, "Ziggy Kerman and the Spiders from Duna". The idea is to send a probe to Duna to verify the rumors that Duna is inhabited by giant robot spiders. Ship design required a probe with 5 instruments. Hardest part was just figuring out where to mount them. 1,000,000 credits for ship design was overkill really. I was pretty wasteful and yet at 554k I didn't feel like there was anything else the probe needed. Ship flew fine ... ... and made LKO with lots of dV to spare It was kind of silly having five science instruments onboard because the mission requirement was simply conduct/transmit any science experiment. And the pressure sensor didn't even work since the required locations were above the atmosphere. The very last task in the mission was to crash the probe into the surface at a specific spot. I managed to overshoot the designated de-orbit spot, so I had to fly the probe in a "J" pattern to hit the target. By the time the probe was finally heading in the right direction, I didn't have time to complete a suicide burn and it hit the surface at ~ 200 m/s. I could have reloaded a save and tried again, but I was happy with the mission result.
  8. I pretty much never use multiple vectors without an engine plate. I'm not sure how adding an engine plate at a fraction of a ton makes much difference when stacking 9 vectors at 36 tons of total mass and 9000 kN thrust though. I do feel the vector is a bit OP overall, but one thing that doesn't bother me is the gimbal range. TBH, it has too much gimbal and I typically scale it down to about 20% when putting them on. Otherwise I find that my rockets will oversteer and porpoise around the prograde vector or in extreme cases actually be torn apart by the extreme gimbal.
  9. Right. I figure that when NASA, SpaceX, or whoever designs a rocket it goes through thousands of hours of design, wind tunnel testing, computer simulations, etc. So if my rocket is a bit too draggy on the nose and it goes flipping engine up when I start the gravity turn, then I assume that's something would have been caught during the planning phase.
  10. Yeah, I was doing some testing at one point and thought I would see how throttle settings mattered by, say, hitting SHIFT 5 times before launch, then 6, 7, etc. I quickly came to realize that sometimes 6 taps would end up being more throttle than 7. It seems like a macro might be able to address this by having the macro correspond to holding down the CTRL/SHIFT key for X milliseconds. Then you could adjust the macro as needed. I don't know a good way to implement that though.
  11. I've found that pressing shift/control doesn't add a fixed amount of throttle, but it's based on how long I hold it. By doing a really quick tap, I've somehow been able to adjust it by 2-3% increments. For a "normal" length press, I seem to get about 8-10%. Unfortunately it's not completely reproducible, so sometimes I get more or less than expected from a single press.
  12. Nice, thanks. I had thought maybe they were a Fight Club type of thing that nobody ever talked about. Those seem like a good thing to motivate me to go visit some few new places in the system. Maybe I'll start a new a career game and work towards checking a few of those off.
  13. I've always wondered what those were. Is this from a challenge? As for me, I tried to do the Acapello (Apollo) 15 mission in making history. Tried is the operative word because it ended up as an exercise in frustration. First task was to build the ship including a Minimus lander with a rover. I really don't have much experience with rovers, but I thought it came out pretty well. Launch went pretty smoothly. The launcher wanted to flip when I jettisoned the first stage booster, but after a couple of reloads and a less aggressive gravity turn I made it into LKO with no trouble. I got an encounter with Minimus at the ascending node right away, and captured with plenty of dV to spare. Since the lander was still attached to the transfer stage, I decided to just use it for the de-orbit burn and then eject it before the suicide burn. Landing target is the center of the little lake down there, but for some reason it didn't show the target outside of map view. That made it hard to make an accurate landing, but I did my best and got close. I ran into the first minor design flaw when separating the rover. Apparently, I had attached the landing legs to the stack separator rather than the fuel tank. When I dropped the rover, the landing legs went flying. It's Minimus though, so no big deal. I just moved the lander and set it down on the engine bells. No problem. I did have an interesting Kraken experience with the rover the first time. The stack separator was still on the rover, and when Bill climbed in the seat it fell off and shot the rover up in the sky at about 50 m/s. Needless to say, I had to reload it after that. Once Bill got in the rover the second time, that's when things really started to fall apart. First problem is obvious - I mounted the seat facing down. I tried and tried to get it facing forward in VAB, but it just wouldn't go at that orientation in any position except on top of the battery (which is where it connected to the lander). I was able to control from the probe core, but it was 90 degrees off. Even worse, it took about 15 minutes to figure out why the wheels wouldn't work. Seems that some were turning forward and some backwards. On Minimus, this was a disaster because at any given time, different wheels would be touching. So when one pair of wheels was touching, the "I" key would move me forward, but when the craft rotated a bit, it would move me backwards. Ugh. I never got it completely sorted out, but after changing the motor direction of some wheels a few times, I at least got to the point I could move the rover. After all the work sorting out the rover, I realized there was a bug in the mission. Although it was showing that the next task was to go to the digging point, it wasn't displaying it on the map. The point you see on the nav ball above is actually the landing site even though "Land on Minimus" is marked complete. And nothing shows up on map view either. There's a lat/long listed, but I don't know how to tell my current lat/long to go find it. After about an hour messing with this, I decided it was a bug and gave up on this mission.
  14. Tonight I went through a couple more Making History missions. First mission was Sally Hut (Salyut) 1. It was basically just a glorified rendezvous mission: launch a station, then launch a 'Soy-ooze' capsule up and dock with it. Both docking ports were inline, and I did find that getting them to line up was challenging. I managed after two or three tries though and got the gold medal. The second mission was the Acapello (Apollo) 13 mission. This was a series of failures that made the real Apollo 13 look tame, plus the mission still managed to land on the Mun. I actually thought a lot of the failures ended up being pretty trivial compared to some of the self-inflicted wounds I've had from poor ship design. For example, failure 1 was an explosion of the 2nd stage engine. That would leave you short of fuel, except that when it happened, I still had 1150 m/s in the 1st stage. I used the 1st stage engines to transfer to / capture at the moon and arrived with an almost full CM. The second failure was that after Jeb landed on the Mun (they recommended I only send one Kerbal, and I guess he was the most expendable) the engine of the lander exploded on ascent. The instructions said to bail and use the EVA jetpack to get into orbit, but I found there was enough RCS thrust to get the lander into orbit and set up a good rendezvous with the CM. I didn't have enough left to slow down or dock, so Jeb did have to bail and swim the last few hundred meters back to the ship. The last failure was that the parachutes blew up on re-entry. The solution was to have the kerbals bail out and use their personal chutes. The hardest part was figuring out how to do it. You have to EVA a kerbal, let go, then immediately tab back to the CM. If you wait too long, the game will tell you that you can't change craft in the atmosphere, and anyone left in the CM is toast. So EVA, tab back, EVA, tab back, EVA. And then open chute, tab to next kerbal, open chute, tab to next kerbal, open chute. Once their chutes were all open, they stayed within physics range and I was able to just tab between them and land one at a time. I must have been too slow somewhere on the mission, because I only got a silver for it.
  15. Hi all, I did the Munar-1 mission in Making History last night. At the end of the mission, they ask you to splash the Apollo-style command module down at a point in the southern ocean. Lat -35; Long -85. I found this to be the hardest part of the mission. Coming from an equatorial orbit around the moon, I needed to do a plane change of at least 35 degrees to make it happen. Problem is that trying to get the plane change right and time it so that the target has rotated under the inclined orbit at the right time is really tough. What I ended up doing was setting up a plane change of ~ 40 degrees just after leaving the munar SOI (when it was cheaper), then capturing into an elliptical orbit around Kerbin. On the second or third orbit, the target rotated close enough to my orbit that I was able to get within the 150-km radius by applying several degrees of normal burn along with my de-orbit burn. This setup was far from ideal though. I had to burn over 1400 m/s of fuel, and I also had to burn a lot with RCS thrusters to tune things at the very end. I'm wondering if there's an easier way to target a location off-equator like this. Ideally, I'd like to be able re-enter directly from the mun for scenarios when the fuel budget is tighter. I've heard the trajectories mod will put an 'X' on the map at the location where it estimates your craft will land. Is that the best way to do this? Are there other options to make this easier?