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KSP2 Release Notes
Everything posted by DerekL1963
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Yeah, no. Dangerous is dangerous. If an ocean vessel, which is a threat to a port where millions of people can live, are legal to own - then it doesn't make sense to limit the ownership of spacecraft on the same basis. (You're forgetting the cargo shipmate - that's a much larger threat than the hull itself.) And there's marginal shipping companies aplenty moving dangerous cargos across the oceans. (One such finally got caught, and it was their seized and improperly stored cargo that took a chunk out of Beirut recently.) And when it comes to Han Solo, same mistake. There's plenty of airliners and large bizjets in private hands.
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totm october 2020 Airplane Design Q&A
DerekL1963 replied to mikegarrison's topic in Science & Spaceflight
Ramjets want high speeds and high altitudes for maximum efficiency (or even decent usability), and that's a pretty niche application. Scamjets are still in the process of consuming flaming truckloads of money in hopes that they'll someday be a) practical, and b) useful. Given that they also (like ramjets) want extremely high speeds, I have my doubts about "b". -
TFW when your lifter is just a hair too efficient...
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Your complaint isn't that MJ isn't working, your complaint is that MJ/KSP has a graphics bug. These are nowhere near the same thing. The best place to report a bug is in the MJ support thread.
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I'm looking at it right now, and there's no text about making a copy. A version number/effective date would be of the date you released it into the wild. You only need one, so people can compare to their personal copy.
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So. Much. This. It's also why I laugh uproariously at the fanbois who go about "getting off this rock so we can survive an extinction level event!" Getting off this rock is the easy part. Surviving Thriving after a complete loss of support from Earth (as opposed to merely prolonging the agony) - that's the hard part. But they never talk about working on that part. Just the easy, sexy parts.
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It's not impossible to do. The trick is to ensure your burn time doesn't exceed 1/4 of your orbital period. (Preferably closer to 1/8.) If you have a 20 minute burn, you want to be high enough to be in an 80-160 min orbit. That minimizes the amount of correction you'll require because of spending too long thrusting off prograde.
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For Questions That Don't Merit Their Own Thread
DerekL1963 replied to Skyler4856's topic in Science & Spaceflight
Just a suggestion.... Getting your information from YouTube is only slightly better than getting it from an Oujia board or from a random text generator. On any given topic, there's a couple of folks who know what they're talking about... But they're vastly outnumbered by the 99.99999% of Tubers who haven't a clue. -
Welcome to the wonderful world of KSP! As always, YMMV... No offense intended, but you're wrong. MechJeb doesn't do "everything" for you... You still need to properly design the vehicle and the mission. (MechJeb doesn't design, doesn't tell you if the design is good or bad, and can't save you from a bad design.) You still need to make key decisions, even if MechJeb then executes those decisions. (Such as deciding on orbital altitude, when and where to land, etc... etc...) MechJeb is a tool, not an "easy button". I use MechJeb for two reasons: - My enjoyment from the game comes from engineering the vehicles and designing the missions and mission techniques. When my lander plops down on Duna, it's because I did all the hard work and skull sweat that it made it possible. All MechJeb did was (essentially) execute the script I wrote on the hardware I designed. (I say "essentially executed the script" because you don't actually write a script, you punch buttons when it's time to punch them. But you decide when it's time.) - With my eye/hand coordination (or more correctly, the lack of), it would be impossible to play KSP at all. Use MechJeb or not, either way is fine. The only mistake you can make in this regard is to listen to the fools who talk trash about MechJeb, who misrepresent what it does, who call it "cheating", who try and imply that you're somehow a lesser person for doing so. It's your game, play it your way. There is no One True Way to play.
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Need to add a note at the top with a version number or effective date, and telling people they need to make a copy to use it themselves. Other than that, great contribution to the community!
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LOST... Old concepts to project never going off paper
DerekL1963 replied to a topic in Science & Spaceflight
They used it to some degree on practically every flight. This file [warning:PDF file] only runs through STS-88, but it shows the amount of cross-range used on each landing. Not quite. Certainly they may have had Edwards planned as a contingency (in case the weather was bad at the Cape), but just because it was planned (whether a nominal landing or a contingency landing) doesn't mean they didn't use the Shuttle's cross range capability to execute the landing. For example: STS-79 was planned for KSC [warning:PDF file], landed at KSC on schedule in the first planned window, and used 777nm of cross range (see first link above) to do so. That's why I said what I did above: You could argue they used the capacity because they had it... And I wouldn't disagree. But you can't honestly deny that it's a useful capacity. (It would probably have been better to provide it via OMS than wings though...) -
LOST... Old concepts to project never going off paper
DerekL1963 replied to a topic in Science & Spaceflight
I didn't say there were aborts on EDL... What crossrange does for EDL is increase the number and width of landing opportunities. With no crossrange, your orbit has to pass more-or-less directly over your landing target... How often does that happen? The more crossrange you have, the further your ground track can be from your landing target and still be able to reach your target. It increases your abort-from-orbit options, but I don't think you can do much about increasing your EDL options by any significant amount. Yes, the US has plenty of airports. However, it doesn't have many airports that can be shut down and all traffic diverted on short (<6-8 hour?) notice without massive (and unacceptable) disruption. And few of those remaining are going to have the capability to recover a shuttle... Ground support is an issue, as is the ability to support ferrying. (If you're talking a fantasy beast that needs no more support than a conventional airliner and can self ferry... We need to be over in the SF thread.) The jet engines were there to modestly increase cross and along track capabilities. (I don't believe any but the most far-fetched designs were capable of self ferrying.) I don't think swing wings will save mass... You still need 'x' wing area for 'y' capability - and you add in the weight of the hinging mechanism. And if you want cross range, I suspect they're going to have to deploy prior to entry anyhow. -
LOST... Old concepts to project never going off paper
DerekL1963 replied to a topic in Science & Spaceflight
The question is: How small, really? Reading Jenkins, crossrange (or the lack thereof) was already becoming a problem even before the USAF was dragged onboard. Even without the USAF's high crossrange requirements, crossrange is Really, Really Useful in routine operations. Crossrange allows a wider range of abort options and widens landing windows/creates landing opportunities (as compared to less or no crossrange). Increasing crossrange trades weight for safety and operational flexibility. (And it should go without saying that all real world designs are the product of endless trade-offs and compromises.) I've said it before, but it's worth saying again: You have to be really careful using concept art to evaluate "what might have been". There were multiple configurations being examined in parallel, so there's no "one path" of evolution to trace. Also, some proportion of that art is all but outright fantasy - they needed a Shuttle in the picture, and so they put a Shuttle in the picture... It may or may not trace back to an actual design study. -
No, you do not understand me... You need only one node to depart Dres. Once you're out of Dres' SOI, then you set up a "Fine Tune Closest Approach" node for a mid-course correction to correct for any errors in the departure burn. It's unusual to miss that far, but you can correct with "Fine Tune". That (estimated) total d/v covers departing from Dres, and capturing (circularizing) in Kerbin orbit, you can't set up the latter burn until you're actually in Kerbin's SOI. MechJeb does not account for mid-course corrections, it has no way of estimating the required size of the correction because that's unknowable until after the transfer burn. MechJeb is a tool, and the best way to understand it it to actually use it.
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Honestly then, I have no idea what's causing your problems... assuming you're running 1.10 or 1.10.1, you've got the correct version of MJ.
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You've got something very weird going on there... You don't have any physics or game altering mods installed do you?
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LOST... Old concepts to project never going off paper
DerekL1963 replied to a topic in Science & Spaceflight
You need to have customers willing to buying the services, then you'll have outfits willing to spend the money start popping up. That's the chicken-and-egg problem that's been holding back development for decades. You can't get customers without the capability, but you can't get capability without customers. -
Yeah, that's an ongoing bug in MJ. Usually I delete the node and try it again.... Either way, if it creates the node and the results look good on the map screen, you should be good to fly that node. If you're departing Dres (actually most situations), one node is all you want, one node is all you need. (Setting up more than one node can cause problems, because subsequent nodes need to take into account any errors in previous nodes/burns.) Once you're clear of your departure SOI, you can set up a "Fine Tune Closest Approach" node. But looking at all the information on the screen, I think I see the real source of your problems, and it's not MechJeb. It's your TWR, .06 is insanely low. Trying to fly that lengthy burn time directly from low orbit is invariably going to lead to gross errors and significant correction burns. My rule of thumb (honed over many years) is that your burn should be no greater than 1/4-1/3 of your orbital period, and preferably closer to 1/6-1/8. (And even with that method, a TWR of .06 is still insanely low.... Long burns and accurate burns are all but mutually exclusive.) With a TWR that low, if you want to depart from low orbit, you need to be departing Dres using a series of periapsis kicks - which MJ doesn't do.
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LOST... Old concepts to project never going off paper
DerekL1963 replied to a topic in Science & Spaceflight
Quoted for truth. We'd finally be able to sort out the ones that just might work with some development from the batstuff insane ones for starters... Some of the stuff they were suggesting in the 60's, well they didn't have the information. -
LOST... Old concepts to project never going off paper
DerekL1963 replied to a topic in Science & Spaceflight
0.o The DC-X/DC-Y/Delta Clipper series of experimental vehicles were designed to prove exactly that - that a booster could be landed vertically. Yeah, the Delta Clipper was supposed to eventually grow into an SSTO somewhat akin to Roton. It's not impossible that it could have done so, but most folks who worked the numbers thought it unlikely. But the real point is that people were talking and thinking about landing large spacecraft vertically while Elon Musk was still in college. Yeah, there were other folks chasing other means, but that doesn't invalidate the existence of the people thinking and talking about vertical landings. There's a lot of people, people who know what they're talking about, that look at the F9 and look at the Delta Clipper series and regard the latter as a huge missed opportunity. I've tuned out on that discussion because it's a waste of electrons, what's past is past. Ultimately, no. As with so much else, SpaceX stood on the shoulders of giants and got across the finish line first. Musk's magic isn't in the concepts. Nothing SpaceX has done, is doing, or is planning on doing is really new... Musk's magic is in having the money, and talking other people into committing the money, to actually try those things at scale. -
LOST... Old concepts to project never going off paper
DerekL1963 replied to a topic in Science & Spaceflight
A popular misconception, but completely and utterly untrue. Not only did people think it could be done - but DC-X actually did it... in 1993. (And the planned but never built DC-Y would have done so from a suborbital trajectory) I think Armadillo Aerospace was also playing around with the concept at a smaller scale in the late 90's. Found my old blog entry... Also, Armadillo was hovering a small scale rocket powered test vehicle in the early/mid 00's. (IIRC, they intended to scale it up into a full-scale X-prize competitor.) I don't think off the top of my head that they were the first... ISTR to recall a Japanese company tossing around the same general idea around the same time. Despite the nonsense tossed around by Space-X fanbois and ill educated space advocates (sets between which there is considerable overlap), Space-X didn't invent the concept and weren't even the first to try it. Nobody intelligent (or at least not having a dog in the race) thought it was impossible. More difficult than it turned out to be, but nowhere near impossible. -
Mistyped because I was also paying attention to something on the stove... "The initial departure burn _should_ provide a much closer encounter."
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Yes to both. I'd launch with closer to 4k d/v, preferably 5k... but that's just me. The initial departure burn _should_ be much closer, and then you do a "fine tune closest approach" burn. I have no idea what it isn't or why your d/v counter is changing.
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The easiest way is to launch into a parking orbit, and then select "transfer to another planet" from the maneuver planner. If you don't depart in the proper window, you'll consume massive amounts of fuel. Eyeballing your vehicle, you're going to be cutting it pretty fine as it is. I hope you're not planning on Jeb coming home...