Iskierka

Members
  • Content count

    555
  • Joined

  • Last visited

Community Reputation

64 Excellent

About Iskierka

  1. Frankly, how? I've been searching for at least half an hour and there is no KK settings menu to be found. The .cfg in the folder does not have any obvious option for commnet support either.
  2. This seems like a very nice mod to have - however, at least in 1.2-pre, it appears to be disabling the click menu to add a manoeuvre or warp to. This unfortunately makes it rather unusable.
  3. I can concur on the problem of the new version not working, but I may have found the reason. Because you keep changing the .dll name, old dlls remain in the game folder, and may be given precedence over newer versions. I found an old one from the 1.1.0 beta in my GameData, which I think was loading first. This is why other mods don't change their dll name, so it's automatically overwritten by new versions and these problems don't emerge.
  4. Torchships drives aren't magical unknown widgets - torchships are just a generic term for very-high-power ships. Heinlein's original use of the term meant a handwavium drive that did direct conversion into energy, but this wouldn't be an engine that even creates exhaust, and isn't how anyone else has used the term. From the very page you linked, modern rule of thumb is that a torchship is simply any ship with a specific drive power of 1 MW/kg or greater. For reference, the Saturn V at full power was around 30 kW/kg. The description of a drive with only a photon exhaust would also be pretty terrible, too - photons have awful mass, and so you'll get no usefully high acceleration out of something with a photon exhaust no matter how powerful. Modern torch drives are either fusion drives, antimatter-boosted engines that absorb the energy into something much heavier, or a mix of the two. Occasionally insane ideas like the NSWR pop up, or less insane but still quite crazy ideas like Orion, but it's primarily the domain of large fusion devices. As for the drives being described in the books, there's actually little need to avoid the neutron radiation - they can be controlled, though are more difficult to, and the heat can be cooled off. You'd need very large radiators to do so, yes, but any sane future spaceship would have these anyway, and most of the neutron energy would be directed into heating the fusion fuel, or another expendable that's used to reduce Isp, as you actually don't always want the most excessively high Isp possible once you're beyond the limits of chemical propellants. Lower Isp would increase thrust possible, making it desirable for high-g manoeuvring ships. As a result, the most desirable option is D-D fusion, due to its large abundance - with He3-He3 being a secondary option if some particular design requirement means you do actually have to avoid neutrons, and you can actually create enough to supply your fuel.
  5. Even with ablatively cooled engines, we kind-of end up in the same situation, however, as the ablative material conducts heat very poorly, so the heat is absorbed into the outer layer, that layer breaks off, and then the heat is gone, leaving none added to the engine itself. Also, the ablatively cooled engines still generally use regenerative cooling in the combustion chamber and fuel pump, which are the two parts which you'd actually expect a failure in - particularly ones related to heat.
  6. The problem with the momentum approach is that that momentum is shared between the craft, fuel that is yet to be burnt, and fuel which you have already burnt and thrown out the back to gain that momentum. Calculating the distribution of this momentum sharing, you'll end up at an equation that should be directly equivalent to the integration approach, since the immediate suggestion of how to do such would be to convert the momentum equation into an acceleration equation, which then ends up at the same first equation.
  7. The issue in-game is that the engines neglect the actual method of cooling used, which is to pump fuel or oxidiser round the engine and absorb the heat, which is then burnt and thrown out the back, meaning that even though the engine is absorbing a lot of heat from its fuel, the net heating effect on it is negligible as the heat energy is expended from the vehicle. In KSP, engines simply produce a fixed amount of heat power as they run, rather than reaching a self-sustaining equilibrium, and this (very small, considering) amount of heat must be absorbed by other parts, or conducted, convected, or radiated away the same as, for instance, electrical heat, even though they're two rather different kinds of heating being experienced due to their cooling mechanisms. Now, real components -can- be slowly burnt through, but this is because of design or manufacturing flaws, not just a gradual build-up during operation. It's also specifically burning through the flaw - such as how on Challenger burning solid fuel forced its way out through the O-rings - not simply a heat build-up leading to gradual failure. Most materials, simply being heated up, won't suddenly and abruptly fail after being exposed to a certain amount of heat, they'll lose strength as they approach a failure point, and so these components will be designed to not move towards that failure point to begin with, as you don't want to play with how close you can get to failure on a weakening component.
  8. I'm not sure why people are trying to bring in more complex factors when the calculations in the initial post are wrong. If a plane is travelling at 200 m/s forward, and ascends to the point that it reaches 180 m/s, then regardless of the rate it does so at or its aerodynamic efficiency, the absolute maximum height it can gain is: E1 = 1/2 200 ^2 = 20000 J/kg E2 = 1/2 180 ^2 = 16200 J/kg E1,2 = 20000 - 16200 = 3800 J/kg h = E/mg = 3800 J / 9.81 m/s^2 = 387.36 m Which is drastically higher than initially calculated. Of course, it'd never be able to reach that height, as drag would steal energy on the way, and it'd have to follow a ballistic ascent, meaning non-linear vertical speed, but that's the maximum possible without engines adding in energy. If you're considering engines, then the arguments about energy exchange go out the window since you're able to constantly add more. As for your calculations with the vertical acceleration, they're even more wrong, as you're starting with a plane that is travelling 200 m/s horizontally (or mostly horizontally), but then trying to determine accelerations from its vertical motion, which is unknown without quite a few further calculations. Addendum: it's also kind-of a wrong question. If you'd started with the correct values, then you might've come up with a particular minimum deceleration the aircraft experiences. You then ask what happens if it accelerates less than that, and surprise, the numbers that come out say the aircraft has managed to gain energy - well, of course! That's why that's the minimum deceleration, because a lower deceleration breaks physics, and is therefore impossible. It'd be like if I gave you a baseball and asked you to, using only your own arm and no extensions, throw it a kilometre up - there simply isn't the energy available in human muscles to come close to that. You can calculate what it'd require - 1.46 kJ of energy and a starting velocity of 198.1 m/s - but that doesn't mean the system we're considering contains the capability to achieve that.
  9. For IAS to increase as TAS decreases takes a very specific, very shallow (and notably, not dangerous) dive. Additionally, the dangerous mach tuck dives are caused when mach tuck reduces control authority on elevators to the extent that the aircraft cannot remain level - not only do you lose control and thus would be unable to pull into a safe dive, but you would likely over-stress and destroy the airframe in the process, so such a dive is something you'd just avoid altogether by providing sufficient control authority. If your aircraft did survive, it most likely stalled, then being at very high alpha it'll have very high drag, so it'll slow down by itself, regain authority, and you'll just perform regular stall recovery manoeuvres, totally unrelated to attaining a specific dive rate that causes IAS and TAS to trade. And such a shallow dive would most definitely be deceleration - by all external measures, the aircraft is losing speed. IAS is not a measure of actual speed, only an equivalence for getting reference aerodynamic performance, as things like the maximum L/D point remain almost unchanged IAS across all altitudes. Thus increasing IAS is not an indicator of acceleration or deceleration, so we only take TAS, the one that actually represents something external to the aircraft's dynamics.
  10. Actually, sound doesn't get quieter faster in space by significant amounts. In space, the problem is that there's not enough air to create a sound in to begin with. However, if you have say, some unreasonably large cymbals, and crash them together in very low orbit (definitely under 200km), they may still be able to make an audible sound, and that sound will still propagate at a similar speed to sound at the surface. Only similar, however, as it may actually travel faster, since the uppermost reaches of atmosphere can be hotter. EDIT: reconsidering, there's probably no orbital altitude where even unreasonably large cymbals could create audible noise, and the velocity of orbit would interfere. But say you were on a floating platform at 50 km or more - pressure is getting remarkably close to vacuum levels. Here, such cymbals may be able to make some audible noise - but it would only barely be audible. However, as suggested before, that sound would travel just as fast - by the graphs provided before, around 330 m/s at 50 km, versus 343 m/s at sea level. As for your other question, I'm not sure what you're trying to ask, honestly. A plane in a dive will experience a "forward" force component from gravity as its flight path is tilted, and at any significant tilt, this will always cause acceleration. It's only possible to keep speed under control in a descent by taking it very gently - for modern airliners in a clean configuration, this can easily mean descending at less than a two degree angle, to keep the aircraft at a constant speed, because the airframe is so efficient that it requires that little forward pull from gravity to go forwards.
  11. SR-71 doesn't actually "fly perfect", it's a very limited airframe. But, that does not mean you got the balance or shape correct at all, and aircraft are highly sensitive to even small changes. Just visibly looking, I can tell your vertical tails are too vertical, too far forward, and too long, and your wings are too narrow if you were trying to make a replica. But these things aren't necessarily your problems, and you definitely should go look up advice on how to build aircraft if you want to make something that works in FAR. As for stock supermanoeuvrability, that's because stock aero doesn't model even basic things like stall that old FAR did, making very extreme-performance designs very easy. Extreme performance is possible in FAR, if to a slightly lesser extent, but requires much better design.
  12. As mentioned later in the post - instead of building just one $500 million satellite that you lose, build two for $200 million. This makes the satellite itself cheaper, and eliminates most insurance cost - as the insurance would be paying out for lost revenue and replacing the satellite, the former of which is drastically reduced, and the second of which is non-existent, though will re-emerge at much lower value if the second has to be launched. Also, your packaging argument is poor. Even if demand was raised, manufacturing significantly more rockets than currently are would be very difficult. Flatscreen TV production is not limited by your ability to produce cardboard boxes, nor their odds of exploding in-transit. Airlines, as much as you try ignore it, are a much more apt comparison - people, like satellites, are very expensive things to lose, much more so than the vehicle carrying them. Aircraft have many of the same expectations of reliability as rockets - arguably even more so, as a lost passenger is genuinely irreplaceable, and comparable value to a small satellite. This isn't a one-way street - dramatically cut down insurance cost, and bigger risks are taken as a failure can be financially endured. I'm talking about precisely the reverse effect, where a smaller insurance, launch, and satellite cost means bigger risks are allowable, which in turn means that satellite costs are cut down further. Cite where an airliner has been taken out by one engine failing, as its dominant flight mode is aerodynamic and thus has the same capabilities? TPS failure is not a launch concern, so would only affect payloads that have already failed in another way, structural is no more likely than any other vehicle, RCS failure is a risk for rockets also and very rare, airliner landing gear is already fail-safe, avionics is reliable, and you're not specifying anything with high chance of failure. It contains precisely one unproven technology, the engine, which will be proven in ground tests long before a vehicle is ready. As a result, none of these failures are any more likely for a vehicle such as Skylon, which also has more fallback capability, as it is designed to be the first LV with sensible RTLS capability. And given the number of failures that are directly as a result of staging, either by mechanism failure or by one of the multitude of required engines failing, I'd more trust a vehicle that has only 4 rocket motors and one OMS to check over, than any staged vehicle. I have, as reduced launch cost and more reliability, or ability to be re-launched when reliability fails, allows satellites to be manufactured to lower standards (the high cost is because of the sheer level of quality required, not that the tech is inherently expensive at any quality). Scaled economies and standardisation are not required, though would help - if you read up, another post cited a very clear option for one kind of satellite that would benefit these, though yes, most satellites are specialised enough to not. As for how many are needed - more than current, else the launch slots would not be booked up for at least half a decade. If launch costs were lower, then also more options could be considered, such as using lower altitudes for comms, and thus getting less latency. For this, you need greater coverage, which means more launches. Currently such a market is limited by how many it is sensible/affordable to launch, not what provides the best service. Lost sale fallacy that we see in piracy arguments so often - if you set up your launch service by dramatically over-specifying and delivering far more LVs than are interesting, sure. Having one LV that achieves 70-80% utilisation is not lost money, however - it will not incur significantly higher maintenance costs by sitting around for a week after each launch. Could earn more money, is not equivalent to losing money, so long as profits are coming in. And having sub-100% utilisation on a reusable vehicle allows, as said, for quick-inserts such as replacement launches when a spare satellite was on hand, or for a payload that was with another service to transfer over should a failure occur and their launch be cancelled. It is a poor way for disposable rockets to operate, as you're literally making more of a thing than you need, but making one of a thing that can do more than it needs to is not inherently flawed. Airliners are almost always at sub-50% utilisation, yet airlines are functional as a very low-margin business - if it didn't work profitably, they're the last business that would be allowing it. Depends on mode of operation. The previous flight proves the components on the vehicle work - so long as high-wear components are checked and verified, then low-wear components are not a risk, and this previously-used vehicle is therefore more reliable than a twice-tested-now-launch component seen on a disposable rocket. SpaceX certainly realise this would be the case, allowing them to repeatedly recycle engines, and then dispose of older ones on the upper stage. And this mode certainly works for aircraft, which have a much higher safety requirement than rockets. Again, only reason to go for the $500 million sat is because you only have one shot at the launch. If you can relaunch soon in the case of failure, then making two for less is a better option. And insurance cost will be dramatically less for two $100mil sats, as the insurance doesn't actually have to pay out any significant money in case of failure, as you already have your spare and aren't losing revenue. Insurance will only have significant cost if the first fails and they then have to fund the second - and the second launch is going to be more reliable for little extra cost, as the failed components can be checked and verified more thoroughly.
  13. A quick google will immediately reveal that is false - example, $290 million for a hurricane-tracking satellite. $390 million for something that can track missiles, for example, to give warning to people in the various civil war zones around the planet. "Dozen million" might be the cost of a Soyuz-launched satellite, but hundreds of millions is normal, and not even high-end, for larger satellites with significant jobs. Notably, Soyuz-satellites would already be experiencing a number of the effects I'm referring to, as Soyuz has relatively very low cost and very high flight rate and reliability, significantly reducing risk and allowing more to be taken.
  14. Also consider that the biggest reason space costs so much is because it is a high-risk venture. First, you need to trust that the LV won't fail during launch, and will deliver you to the required altitude, then that your circularisation will work, and then that your own satellite won't fail. Satellites cost hundreds of millions to billions of dollars because of this last point - any of these failures mean you don't have what you wanted in orbit, and you don't want it to be that your own satellite failed being what's losing you money. Plus, the next launch slot is years away, so even if you had a spare satellite, you might endure dozens of months of lost revenue. A rapidly reusably launch vehicle, however, drastically changes this landscape. Suddenly, the next launch slot isn't years away, it's weeks away even if they only get a small improvement in flight rate. With a big improvement, you might fail on Tuesday and be trying again on Thursday. This allows companies to take a bigger risk on their satellites, dramatically cutting their cost. If SpaceX considered something like trying to reland the entire stack in emergency, including upper stage and payload, they could have a non-destructive abort method for problems that emerge early in the first stage - a rather limited circumstance, but one that could save the customer significant money if they're not losing their payload. And a reusable SSTO such as Skylon is unrivalled in this situation - a failure at any point, including satellite activation, is not a permanent one, but one from which you simply re-attach the payload and fly back to base, to allow repairs to be made. To have a catastrophic loss, Skylon would have to suffer either total hydraulics failure or a simultaneous quad-engine-failure, both of which are immensely improbable. Any stage of this cost reduction from reusability also reduces cost of satellites, as above. Space is a very limited market because only people who are -absolutely sure- that their billions are worth it are willing to risk it. If you bring that down to hundreds of millions, then that dramatically increases the number of people who will consider risking the money, as there are always more potential uses of space, even if they're only some variant on Earth observation. I'll bet the companies that now provide farmers with maps of where their crops need fertiliser the most took a significant risk before it paid off, and lowering the cost allows more similar risks. If you bring the cost down to tens of, or even just millions, by almost totally removing risk from space, then you dramatically widen the market, as more and more potential uses can be seen, and at those prices, even universities may justify the launch cost on occasion, and make use of the opportunity to conduct all kinds of new research. In the end, even if a higher flight rate does not get utilised, the fact it exists dramatically reduces risk, and will in conjunction dramatically reduce the cost of satellites. Two $100 million satellites are, between them, much less likely to fail than one $500 million satellite, and you don't have to go through years of lost revenue should the first fail.
  15. One thing about the shuttle is it massively over-promised, as quite late in the program after many conflicting requirements massively cut down anything it could realistically do, they were still using early quotes from simpler, more functional designs that would have had more development funding available, and thus been able to be made much more capable. The final product was one different to what they were advertising. Big difference with everyone else, including SABRE and Skylon, as well as all the partial reuse options, is the proposal being offered is the same as the one intended to be provided, since they won't have massively conflicting requirements placed on them by governments and militaries. They're simply developing whatever they think is the best option and giving realistic reusability figures for the actual proposed vehicle, instead of one only tangentially related. Effectively, the shuttle's quotes were lies, but they were forced to lie, because they couldn't be honest about how bad the conflicts were making the vehicle's performance. Yes, projects can over-promise and under-deliver, but in the shuttle's case, you only over-promise and under-deliver that badly when you're forced to deliver a vehicle that wasn't what you were promising.