Starman4308

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Everything posted by Starman4308

  1. Starman4308

    Do you know what Advanced Tweakables are?

    Oui. You're probably going to see veteran players over-represented in this poll, though, so your statistics will be off. Unfortunately, like many games this complicated, things will slip through the cracks for new players as the game attempts to gently feed them with a fire hose, instead of the entire city's water output at once.
  2. Starman4308

    SpaceX Discussion Thread

    It's an iron-nickel-chromium alloy noted for corrosion resistance and resilience to temperature and pressure. It's commonly used in aerospace applications as a result; it's hard to work with, but quite robust.
  3. Starman4308

    What did you do in KSP today?

    Nothing special, necessarily, but: Test Flight gives unused engines with 0 Test Flight data minimum reliability. I was at roughly 60-70% of maximum data on these engines, probably on account of tech transfer from having used earlier versions extensively. By the end, know I was past 90% of maximum data, possibly all the way to 100%.
  4. Starman4308

    What did you do in KSP today?

    I'm not yet done with backlog, but this mission was kind of cool. All glory to Agathorn. The goal was to place a test satellite into GEO, using my new-generation Atlas boosters. All of the main engines were upgraded; an AJ10-42 became an AJ10-104, the LR105-NA-3 became the LR105-NA-6, and the LR79 (S-3D) boosters became H1 (Saturn 1 version) engines. Each and every one of them with more thrust, more specific impulse, longer burn times, and higher max reliability... and I finally had a restartable upper stage. Naturally, the first one had the LR105 sustainer fail to ignite, followed by deliberately dumping it into the ocean after clearing the pad. I usually catch failures-to-ignite before I release the clamps, but I wasn't paying enough attention The second time around, I was very careful to make sure all three main engines and both verniers were at full thrust before releasing the clamps. Then the LR105 sustainer suffered a loss of thrust, producing just 50% of normal thrust. I lofted more than usual, knowing that every meter/second of vertical velocity provided by the H1 boosters would be needed for any chance at an orbit. As the core slowly burned through its propellant with TWR < 1, I pitched up, first to 32 degrees, then 45 degrees, as I watched vertical velocity sink from +900 m/sec, eventually falling to -85 m/sec. But, burn through its propellant it did. Vertical velocity rose, and pitch fell, back down to 32, then 20, then 12 degrees. At this point, I became increasingly confident that the mission could be a success... if the core stage burned to depletion. The LR105 was rated to burn for 5 minutes 50 seconds, and the verniers for 6 minutes. It was now minute 9, and Test Flight's predicted chance of engine failure began to soar. I needed those last few seconds of LR105 burn time. While the margins were generous... they were not so generous as to permit the loss of over a kilometer per second of delta-V. Twenty seconds. Fifteen seconds. Ten seconds. Eyes on the Test Flight display. Five seconds. T = 10 minutes, 25 seconds, and nominal burnout from LOX depletion. MECO. Stage separation. Second stage ignition, and that AJ-10 was A-OK. While the satellite had to complete the last 250 m/sec of the GTO burn on the second pass, it had more than enough hydrazine reserve to still make it all the way to GEO with a healthy remaining delta-V margin.
  5. Well, I can't say this was unexpected. Every dollar spent on trying to communicate with Opportunity is a dollar not spent on many other worthwhile NASA projects, and it's been becoming increasingly clear that we're not likely to get Opportunity back. It's been a good run for a rover whose design goal was a mere 90 sols of operation. Beyond the mere science, the "rover that wouldn't quit" has become something of a cultural icon, a legend in the history of space exploration.
  6. This bit is being taken out of context. Except for the 3-line header, no part of this is about Blue Origin; it's about issues between Bezos and a man named Pecker, who runs the National Enquirer. Still, Blue Origin is out ahead of literally everyone except SpaceX, has what appears to be a more safety-conscious culture, and Jeff Bezos has deep enough pockets to ride out many years of not being the top competitor. After all, even in this era of Falcon 9 being incredibly popular as a launch vehicle, nobody's yet folded. ULA, Arianespace, Roskosmos, ISRO, JAXA, China: they're all still flying, often with commercial payloads. Northrop Grumman's even throwing its hat into the ring with OmegaA.
  7. Starman4308

    Rescue in LKO

    The orbital elements don't need to be terribly similar for the intercept. All that matters is that: You have a close approach You have enough delta-V to kill your relative velocity at the intercept The intercept is not so incredibly fast that it's hard to get an accurate velocity matching maneuver. A 40 m/sec relative velocity is easier to eliminate than a 4000 m/sec relative velocity. The orbital elements will match up quite well once velocities are matched. Before that point, a near match helps, as it'll reduce the magnitude of the velocity matching maneuver, but it's not strictly necessary.
  8. Starman4308

    What did you do in KSP today?

    Going to clear some more backlog... It can be hard to get a good shot of LES jettison, since they have such a high TWR. As is my custom, it separates shortly after second-stage ignition. First unmanned lunar landing of the career: Pioneer 1 approaches Venus This happened to Cheryl Taylor. Twice. Fortunately, the second time, she was close enough to orbit to finish circularizing on the service module. For my second GEO constellation, I decided to send all four on the same rocket and do the whole "transfer bus at 3/4 day period" trick. Another Pioneer probe swings by Mars This rocket was known in development as "Titan 1", and later renamed to "Titan Fun". Pioneer 3 on its kick stages, heading to Mercury.
  9. That... actually gives me an idea. I'd been assuming a Dragon mounted in the top, with a pyrotechnically separated panel in case it needed to separate in a hurry. But what if... we bolted a Dragon to the side of the Starship? Relatively minimal modifications to the Starship, less damage to the Starship if the Dragon separates in a low-stress environment (such as if the Starship heat shield isn't fully trusted yet)... It'd play havoc with the aerodynamics, yes, but with the sheer excess of payload capacity and non-trivial gimbaling capacity on the Superheavy, it might be doable.
  10. Starman4308

    Looking for "Engines GUI" Mod

    I'm pretty sure that's part of SolverEngines, which is bundled with Real Fuels. I'm not sure it's intended for standalone use.
  11. Starman4308

    return of a newbie/ help Duna

    The simple solution is going to be to disable CommNet in the difficulty settings. This is the WIki article on CommNet: I cannot verify whether it is accurate, since I don't play with stock or CommNet (I use RemoteTech instead). If the Wiki article says "only when close", that means it can reach when the planet is close to Kerbin, whereas if they're on opposite sides of Kerbol, it may not reach.
  12. Starman4308

    Multi stage help

    When optimizing for mass, frequent staging should be your preference, especially asparagus/onion staging. The quicker you shed dry mass, the better. Dry mass is the enemy of the Tsiolkovsky equation. When optimizing for cost, it gets a lot trickier, since engines and decouplers are fairly expensive relative to propellant tanks. Because of that, cost-optimized launch vehicles tend to be a bit propellant-overloaded, becoming heavier and likely incurring extra gravity losses relative to a mass-optimized vehicle. Stock is relatively forgiving in terms of how often you stage, since fuel tanks are relatively heavy and expensive. Staging "too early" helps your delta-V, ameliorating the cost of excess decouplers/engines. Staging "too late" likely means a slight propellant overload, and while fuel tanks are relatively expensive... they're still cheaper than engines.
  13. Starman4308

    More Long-Term Living Spaces

    Yeah, it's totally ridiculous. After all, we know 100-year grand tours are best done in a chair in an unpressurized 1.25m service bay. In the absence of any sort of mechanic to force players to use actual living space for their Kerbals, I suspect additional passenger compartments are a low priority for development. That said, plenty of mods do add big passenger compartments, and at least Kerbalism (and probably at least one other) forces use of something more than a chair.
  14. Starman4308

    SpaceX Discussion Thread

    While I do suspect the Starship will have a lower ballistic coefficient, that isn't strictly true. The Shuttle payload bay was (usually) empty, the crew cabin had a reasonably amount of empty space, the OMS tanks were drained, etc. Granted, none of that stopped the Shuttle from being something that didn't glide so much as it fell to the runway.
  15. Starman4308

    So what is Serenity?

    You're right. My post shall be edited to better reflect what the players want.
  16. Starman4308

    "Electric charge not generated"

    Stock KSP has both solar panels and RTGs (Radioisotope Thermal Generators), although I don't think they're unlocked at the start. Before that point, many liquid-fuel engines generate electricity when running, though obviously that consumes a lot of LF+O and moves your craft. Fortunately, in stock, I'm pretty sure antennae only consume electricity when transmitting science; so long as you're not reckless about turning your ship and transmitting science, battery life should be enough.
  17. Starman4308

    So what is Serenity?

    If this were true, then... Serenity is going to combine a massive bugsquash, introduce a high-performance rigid-body physics engine, add surface experiments and reasons to actually establish a surface presence, give Duna/Ike a barycenter, rebalance stock part costs and masses to make sense, add GP2, add a suicide burn timer and more easily accessed true-altitude and vertical/horizontal speed indicators, add larger-sized NTR/ion engines, let Kerbals know about the magic technology of "ladders" sooner, add tiny RCS blocks early-game for people who don't want to abuse the reaction wheels, and fix inconsistencies and outright weirdnesses with the aero model. EDIT: And a pony.
  18. To clarify: I'm not suggesting reaction wheels be removed, or even necessarily nerfed. I was attempting to humorously point out that there is another way to make monopropellant necessary. After all, I did put reaction wheels on a whopping four probes for the 1977 Grand Tour alignment. What decadent luxury!
  19. For P2P, you have the issue that you need a landing site that doesn't catch fire when hit by tons of burning methane... and approach control, and owners of very expensive rockets thinking "Hm, it may only cost $9 million to fly... but likely over $1 billion to replace if something goes wrong at the other end". I find it unlikely that somebody would risk landing a Starship at anywhere but a pre-built, designated landing site. For emergency humanitarian efforts, the Starship has to be compared to the dozens of air transports that can be there in less than 24 hours (substantially less if they start nearby), can literally drop non-fragile cargo onto any reasonably open area, and can be based from anywhere with a sufficiently large runway. For more regular commercial traffic, you have to compare it to aircraft that can launch from and land on a very wide selection of runways, can be refueled with standard jet fuel (no cryogenic methane and oxygen), have well-understood all-weather capabilities, and are presumably easier to load and unload. There's also the issue of payloads. Again, this is going onto an enormously expensive launch vehicle, so payloads will need to be vetted for "will not destroy the Starship". That's true of aircraft as well, but A, that's much better understood, and B, there are many payloads that will survive low-pressure, low-altitude flight... but not outright vacuum. Shaving some hours off transit is all nice and well... but air transport is much better understood, has a lot more infrastructure behind it, is more flexible, and a big chunk of the total shipment time is in handling, not in transit.
  20. Starman4308

    Vanilla NO MOD maximum ship speed

    Breakthrough Starshot uses speculative, untested technology to claim they can hit 0.2c. Nothing based on well-developed technology is going to get us to 0.01c. It's not charting a course that's hard. Space is rather empty and positions are well-known. It's getting to the staggering velocities required that is the issue. While there are mods that present players with what are functionally warp drives, the stock game restricts itself to chemical, nuclear-thermal, and ion propulsion. The Dawn engine has a specific impulse of 4200s. To send a 1 kg probe to velocity of 0.01c with that specific impulse, you would need about 4*1031 kg of xenon propellant as a hard lower bound. That is 20 solar masses. The highest specific impulse ion thrusters yet built top out around 20000s. That would require a mere 4,400,000 kilograms of propellant... which is more mass than the entire Saturn V rocket, nevermind the question of how you get 4,400 tonnes to orbit (since ion engines have far too little thrust to launch themselves to orbit).
  21. Starman4308

    What did you do in KSP today?

    As per usual when I take a break from KSP, I think "I can totally just catch up on the WDYDIKSP thread then post". I've... given up on that. So: backlog of imagery, from an RP-0 campaign, then the RP-0 campaign after I realized I didn't have part unlock costs, then RP-1 after I decided to check that out. A totally safe vehicle returns to Earth from a suborbital flight. Incidentally, on one of these, I accidentally steered south, so I can only assume the pilot was defecting to Cuba. A historically implausible rocket: an RD-108 powered core (straight out of the R-7 Semyorka), an AJ-10 powered upper stage (similar to the Able), and a half-dozen A-9 boosters. This is a Soviet core stage, with an American upper stage, and boosters made from an American improvement over a... German rocket. I'm lucky that, even in its few flights, I had only one loss-of-performance on an A-9 booster. Those are not exactly paragons of reliability. My first lunar impactor of the campaign. Vernier engines were used in place of anything restartable, since I didn't have any high-thrust restartable engines at the time. This rocket, which is clearly not a ripoff of the R-7, separates its RD-107 boosters from the RD-108 core stage in what is absolutely not a Korolev cross.
  22. To the best of my knowledge, those are still random Internet commenters and space enthusiasts with no more authority on the subject than you or I. Preaching to the skies about "airliner-like reliability" won't make Starship as reliable as an airliner. Flying it tens of thousands of times will... and there just aren't enough payloads lined up for that in the forseeable future.
  23. Or remove magic torque machines from the game! I've been playing Realism Overhaul for years now and haven't used reaction wheels in around a year. I've forgotten how. Please send help. In a more serious suggestion, I'd maybe see about making the Puff very cheap (and possibly unlocked early) relative to the Ant, so if you have a small vehicle, the Puff may be your go-to, with the Ant as the expensive high-performance option. To expand on answers to this: unlike most nozzles, hydrazine monopropellant is cool enough that you can conceivably skip any sort of active cooling and just have a bare metal nozzle. Without ablative or regenerative cooling, main engine nozzles should be an incandescent mess of rapidly melting metal, but hydrazine is relatively cool.
  24. Right now, PF is distressingly large for orbital launch vehicles. There is no indication Starship/Superheavy will be any different. And separating (PF,PA) just makes things needlessly confusing. For the purposes of this discussion, "failure" is failure to protect passengers. Furthermore, there are reasons beyond that simple mathematical equation for having or skipping safety features: 1) The safety feature is expensive. This is most likely the case for something like a cargo aircraft: the probability of failure is so low that nobody's willing to shell out for expensive ejection seats. 2) The safety feature has an excessive penalty to performance. For example, by the time you add ejection seats to an attack helicopter, you might have added so much mass that you've made it more dangerous by reducing its ability to not get shot down in the first place. 3) Cultural/bureaucratic inertia. See the lack of seatbelts in many buses. 4) Marketing (which is a bit part of Tater's point). 5) There is sufficient uncertainty in failure probability to confidently skip safety measures... like an experimental vehicle that most closely resembles a set of vehicles with an awful habit of exploding. I'm also pretty sure that, like most probability-based things, it's going to be a product, not a summation. Probability of increased failure caused by a Starship LES should be fairly small if it is kept simple and you're not the 1960s Soviets who have been launching orbital vehicles for less than a decade. Ejection at supersonic velocities is very unsafe... as is ejection at hypersonic velocities in near-vacuum. I do not consider them a viable LES. Also, Gemini would've been a better example... for which the ejection seats were considered borderline useless. [Citation needed]
  25. Starman4308

    NASA SLS/Orion/Payloads

    Man, that better not be the case. If that's true, then it might be the next President who gets to unfairly claim credit for a project started by the prior President, itself a near carbon copy of a project started by the President before that, attempting to use 1970's era hardware in a way best designed to funnel money to 1970's era contractors. And that would be... bad? Anyways, I seriously hope nobody dies as a consequence of the SLS, which is composed of so much pork that it could probably win Midwest hog-raising competitions without the judges any wiser.