Birdco_Space

My suggestions for building space stations. 1) Use Senior Docking ports to join station modules, much less bendy 2) Make your modules of a standard mass ( I prefer 8000 kg), this way you can flat pack a station onto a interplanetary booster without too much work of load balancing (or overpopulation of reaction wheels), send a station anywhere, and build it there. 3) Have a probe core near the center of mass of a station, give it the stations reaction wheels, and control station from there. Cuts down on the kraken attacks. 4) if you use mods, Nertea's Near future construction has nice square cross section struts and docking ports that eliminate alignment issues (once you get them docked together). It's surprising how noticeable a 1 degree misalignment is when the component has solar cells sticking off of them. The square cross section trusses also have tanks that can be inserted inside that help with part count if you are building big.

Where your "control from here" is makes a huge difference on the long term stability of a station. My Rapid unplanned disassemblies occur when the "control from here" is located from a component far from the center of mass of the station, SAS is on, and there are reaction wheels on the station. Same applies for large vessels assembled in orbit My fix from a design standpoint. Have a probe core near to the center of mass of the final station or ship, and set it to "control from here" Auto-strut Reaction wheels to "heaviest part", or "root part", depending on which gets them closer to the "control from here" probe core. this will help ensure the reaction wheels work together on the station, and limit how much the cause docking port joints to flex. Limit the number of reaction wheels, and where possible, keep them close to the center of mass probe core. The greatest potential danger for a disassembly occurs when a component with a reaction wheel docks with the station. Have the reaction wheel on that vessel auto-strutted to heaviest or root part has been generally successful for me in preventing the station from detonating on a docking event. Also, use F5 a lot.

In my practical experience (I go to Moho a lot, its a fun place to go), there is a minimum TWR needed at each stage of the voyage to do it for the minimum possible delta-v for Phase 1 ejection, which is around 2200 m/s of delta -v, if the launch is timed right, a TWR of around .4 to.5 is around the minimum needed to get an accurate ejection to Moho. going much less makes the voyage there much more expensive in delta-v, by hundred of m/s in correction burns. for phase 2, this can be done at .1 TWR, though .2 TWR is more efficient. Ion engines shine here, as you only need a quarter of the solar cell mass per Ion engine, therefore it is easy to build the 2000-2500 m/s delta v stage to capture. However, you will more than likely need to capture in a retrograde orbit (not a big deal given Moho's relatively slow rotation Phase 3, landing, you need at least a TWR of .55 to do it easily, lending itself to a stage with around 1200 m/s delta v for just a landing, 2500 for return to orbit as well, with a small vacuum optimized LF O engine. Ions work for return and Kerbin Capture, but you'll need about 4x the mass of solar sells, or a sizable mass budget of batteries for the kerbin capture. Breaking this out: A 1.25 or 2.5m vacuum LF O engine for kerbin ejection. A Ion stage for moho capture, and small LF O stage for Moho landing. Round trip requires a sizeable Ion stage, and docking in Moho orbit. My unmanned surface probes to Moho are launch able with 1.25m parts and asparagus staging, or more simple 2.5 meter rockets.

I name my manned interplanetary ships after British or American Warships, Using names such as Endeavour, Enterprise, Essex, Invincible, ect. Everything else is named after what they do, (Jool heavy probe, Moho ion probe, ect)

The answer is: It depends on what you are trying to accomplish. If you are looking to build a station, higher orbits (within reason) have added value for greater ease of plotting maneuvers to get ships/components. its hard to catch up with a station ahead of you in orbit if the station is at 75km. For relatively high TWR interplanetary missions (talking around 0.5 TWR) with thin Delta V margins, the lowest possible parking orbit is desired, to make the most of Oberth effect. For relatively low TWR interplanetary missions with ample delta-v, higher orbits allow longer burns to be made accurately (or without causing pe to dip into atmosphere during burn). If the final stage of your launch vehicle is very low TWR, higher orbits are easier to obtain, as there is more time before the vessel re-enters the atmosphere to add the required delta-v to obtain orbit. I had a Whiplash/ Dawn powered SSTO that I couldn't get into orbit with a apoapsis below 100km, but it had all the delta V in the world to get anywhere. Bottom line, there isn't one answer to the question, it depends on the entering argument. Personally, I like 90km as my standard parking orbit. easy to get to, Oberth is pretty good there, easy to set up Rendezvous there even if you botch the timing of the launch, it is tolerant to relatively low TWR interplanetary burns

Not easily without mods. 2 mods that may help. 1) Navyfish's Docking Port Alignment indicator (DPAI). in the alignment indicator, there is a readout of the relative rotation between the 2 docking ports. using this you can get relative rotation within a few tenths of a degree of desired orientation. 2) Nertea's Near future construction: Has a docking port that will only dock if they are precisely lined up in relative rotation (at 0, 90 180 and 270 degree relative rotation). This one is important if you want to radially dock something to a spacecraft that will provide thrust axially. The few tenths of a degree accuracy of the DPAI not enough to keep the craft controllable with radially docked engines. Without Mods, there is the old dual docking port method, where you dock to something else using 2 docking ports. This one has always been finicky because to successfully dock both ports you have to be exactly lined up in pitch roll and yaw axis, else only one docking port would successfully dock.

I have a question on how we define payload? Is this weight of craft to orbit, or weight of just the things to complete the mission? do we factor recovery cost into this? I have a SSTO space plane that costs 32k funds, but if recovered on the runway only expends around 800 funds in fuel (plus a few hundred funds on the occasion I derp the landing and remove a wing). The functional payload is only 3 kerbals, but I get the whole aircraft to orbit, which weighs around 5 tonnes when in orbit. So this could be considered tremendously efficient working the numbers right (800 funds for a 5 ton spacecraft to orbit, equating to 160 funds per ton), or not so efficient (32k fund spacecraft to get 3 80kg kerbals to orbit, for 200k funds per ton)

My recommendation for you is to open up the Atmo readouts for KER. This gives you a lot of useful information about optimizing your rockets. The most efficient rockets I have come up with are Solid Rocket stage, Atmospheric rated Liquid fuel stage, then Vacuum rated liquid fuel stage, with the SRM and 1st liquid fuel stage firing at launch. The different stages should be sized as such. The 1st liquid fuel stage should have enough fuel, when combined with SRM stage for about 3000 m/s delta V in vacuum, with a rocket sized to provide 1.3-1.4 TWR at 5km altitude after the SRM have burned out. this frequently involves turning down the thrust on the rocket tweakables. the SRM stage should be sized to get launch TWR at 1.4-1.5 at the surface. This involves tweaking both the main liquid fuel engine and the SRM engine thrust, and where possible having the liquid fuel stage set as low as possible to get the 1.5 TWR at surface, and the 1.3 TWR at 5km once the SRM have burned out. The final stage should be sized for an approximate 0.3-0.5 TWR, with sufficient delta-V to get to your ultimate destination plus the around 400 m/s needed to pay the 3400 m/s delta V bill needed to get to orbit. The more of the 3400 m/s to orbit you put on the launch stage, the more towards 0.5 your vacuum TWR needs to be at stage initiation. With this design, I can get 7 kerbals (payload around 8t with cabins and needed re-entry gear) to orbit for 30k (without recovery), using a gravity turn, and throttling my engine to keep time to apoapsis around 50 seconds until desired Ap altitude is reached. my cargo launches are similarly efficient.

Drop the intercoolers and put a shock cones instead. The flat surface of the intercooler is really draggy. this may also be impacting your controllability.

I think it is important to note, Lift in KSP is a function of lifting surface area and angle of attack. A lifting surface with 0 AOA to direction of travel generates no lift. What the deploy flaps does allows for more lift generation at a shallower angle of attack for the main wing. What I have found is that well placed flaps actually help get aircraft off the runway by generating lift when the main wings themselves may have only a very small AoA, especially for aircraft intolerant of significant rotation on the runway or approaches at significant angles of attack.

I tend to put high power relays in extremely elliptic polar orbits of Eve and Duna. These 2 relays, along with Kerbin, will result in a very high percentage of time in contact for nearly every body, with slightly less effectiveness for Jool and Eeloo, but a lower power relay attached to a normal Science probe can assist in closing these gaps.

To make career more challenging: Turn Technology unlock costs on: Require both science and funds to gain access to new parts. Frequently drives strategies to turn science into funds, and delays full tech tree unlock until you visit bodies outside Kerbin and its moons. Turn off the extra ground stations. Drives an absolute requirement to build out a comsat network, especially if you are trying to get unmanned missions into space. it also limits the approach vectors you can enter other planets at, so you have comms contact when you make your insertion burn. Drive need to place high powered relays at strategic locations in the Kerbol system, or use pilots using relays to control things in system Require comms network contact to control probe cores: the above reason, and it makes your first comms satellite more challenging to launch. Turn re-entry blackout on: added difficulty returning unmanned probes and reusable launchers Increase re-entry heat: works to prevent Mk-1 spaceplanes, which can be ridiculously efficient in completing Kerbal rescue missions in LKO. a well designed Mk1 space plane can recover a kerbal from LKO for under 2000 funds if you land back on the runway, making these stupidly profitable (70k made for 2k in expense, and don't have to hire the Kerbal). Drives the need to use Mk2 or Mk3 space plane parts if you are looking to go to orbit off the runway, or drives design compromises with Mk1 space planes to use them for re-entry.

I'll one up you. I'm and American living with Greece (temporarily), with children going to a local Greek school, but who will, in a few years, be in a school in the U.S.A. We use imperial units at home, when everything else is in metric. every day from my wife "what's 425 in Celsius", "how many grams in an ounce" and "how many milliliters in 2 cups" because all our recipes are in cups, oz. and degrees Fahrenheit, and our oven, scales and ingredients are in metric. Being an engineer, I am fluent in all the measurement systems, but it is hard explaining metric in relative terms. Imperial is definitely easier in that regard. And even more, I'm a mariner by profession, so I think of distances in nautical miles (6076 ft, or 1 minute of latitude (1/21600 of the earths circumference, measured through the poles). That unit is by far the most logical measurement of distance for me, and I can directly relate it to the coordinate system we use for charting. The most efficient way of capturing the energy from splitting the atom is by using water as the medium of heat exchange, and water in its gaseous form is extremely effective at turning turbines, converting the tremendous thermal energy of the fission of uranium into usable mechanical and electrical energy. I'm both an electrical engineer, and a nuclear engineer. the NERVA is my favorite engine in KSP, because I trained at one of the locations the engine was designed and tested (though long before I trained there)

KAC only works when you remember to set alarms (or have the mod set them for you). +1 Vote for KAC being stock.

All you really need for docking, if you are a fan of mods, is NavyFish's Docking Port alignment indicator. Once you learn the interface, it makes docking so much more efficient, and easily accomplishable with just SAS heading hold. Most of my docking maneuvers are accomplished with about 5m/s of RCS delta v once you finalize the intercept and match velocities with your main engines. For RDVU, the most important thing to remember that adding thrust with your heading offset from your retrograde velocity marker pushes your retrograde velocity vector away from your heading on the nav ball, and if your retrograde velocity is sitting ontop of your anti target marker, and you are relatively close to the target, you should have a close RDVU. How I work this is to set up an initial RDVU with a maneuver node either a half or a full orbit ahead ot the expected intercept. warp to a position about 3 minutes before RDVU, then gradually (and occasionally) retrograde burn, off setting slightly to line up retrograde vector with anti target marker. Keeps your engines pointed in the general direction of target (allowing for emergency stops) and gets you there relatively quickly.

Why does Squad inflict upon us the coldly logical mathematical progression of timewarps (x5, x10, x50,x100, x1000, x10000), when a much more natural and humanistic progression is available? (x6 (1/10 min per second), x30 (1/2 min per second), x60 (1 min per second), x 360 (1 hour per second), x2160 (1 kerbal day per second), and x15120 (1 kerbal week per second)). That would make it so much easer to anticipate how many seconds I can hold a time warp before I send Jeb catapulting past his maneuver nodes. I'm also waiting for a mod that shows my masses in slugs (or pounds mass), forces in pounds force, temps in degrees Fahrenheit and distances in miles. I got my engineering degree in the U.S., and all these conversions from metric into the English units I understand makes my head hurt.

1 fund is worth about 1/20,000 of a single Kerbal trip to orbit using a LFO powered rocket (and yes, I can do it for cheaper using SRB). Until we get a cost of a snack, this is probably the only measure of exchange the Kerbals we know care about.

I second this. Laythe encounters are generally easy to arrange when coming in from interplanetary, and it has the mass and orbital velocity to easily capture the vessel in Jool Orbit.

1) Science labs: I play Community Tech tree, and the 10k science node can be hard to get to without a few labs scattered about. 2) Kerbal Accumulation point: I run a lot of rescue missions to fund my space program, and find victims volunteers for my planetary colonies. It is far more efficient to pick them up in a RCS powered lawn chair, gather them at a station, then recover them in groups with a single orbital launch. 3) Tourist Hotel: allows me to use my high capacity Kerbin LKO launcher efficiently to move groups of tourists to orbit, then send them to their destination with high efficiency, space only ships 4) Spaceport: Like an airport, but in Space! 5) Fuel depot: All these interplanetary missions are far more efficient if you reuse craft, and skip the Kerbin to LKO step. also, all those places its easy to get fuel into space are not necessarily the places you need all the fuel.

This mod enables and simplifies the building of multi piece interplanetary ships and space stations. This mod ranks with Kerbal Engineering Redux, Kerbal Alarm Clock, and Transfer Window planner as essential mods that give players the info they need Plan, design, build and fly their missions with the tools available to any competent space program. Thank you so much for the work you do on this mod.

How beautiful and utterly Kerbal. The launch rig must be equally kerbal.

Its all about energy and momentum. The energy of propellant is a function of the energy input, divided by the mass flow rate of the propellant, and this energy goes into bulk kinetic energy and thermal energy. The bulk velocity of the exhaust (and in turn ISP) thus increases roughly with the square root of the increase of input energy (minus Thermal losses) The overall change in velocity is a function of the fraction of the rockets mass thrown out the back and the velocity of that stuff. The momentum change of a rocket increases linearly with the mass flow rate of the propellant, and with the square root of the kinetic energy of the propellant. This correlation roughly equates to thrust as well (since force = change in momentum per unit time) When a rockets propellant is reacted with (be it combusted, heated, or fused), the resultant energy in the rocket exhaust is nearly all thermal, requiring nozzle design to convert this thermal energy into bulk kinetic energy. A perfect nozzle would convert all the gasses added thermal energy into bulk propellant kinetic energy. However, in reality, the more the gasses interact with the nozzle to covert thermal energy into kinetic energy, the more energy is lost to the rocket nozzle in the form of waste heat. On chemical rockets, and fusion rockets, energy imparted into a specific propellant is constant per unit mass, thus thrust increases linearly with increase with increase in mass flow rate (more fuel flow = more thrust) Changing propellants can change the energy density of the combustion (or fusion), and lighter combustion products have greater molecular velocity for a given thermal energy, which increases the theoretical maximum exhaust velocity. However, waste heat generated increases roughly linearly with the energy density of the reaction imparting the energy to the propellant for a given nozzle design and mass flow rate. Fusions massive energy per unit mass also comes with a lot of its own losses, such as photons, neutrons and neutrinos. (Bigger bang = hotter engine) To increase exhaust velocity for a fixed propellant and mass flow rate, one needs more nozzle, which means more of the propellants energy lost to waste heat of the rocket itself, and the exhaust velocity only increasing by the square root of the increase of the kinetic energy of the exhaust gas. In general, this means the waste heat that needs to be dealt with increases as rocket efficiency increases. (faster gas = hotter engine) Thus for a given waste heat rejection capacity and propellant, you can have greater exhaust velocity, but at the expense of a lower mass flow rate. (more ISP = lower thrust) All these factors add together to make it very difficult to raise both thrust and impulse, because it means you have a lot more waste heat to deal with. Logic on NERVA and Ion efficiency is a little different, because of the processes involved. NERVA have a roughly fixed thermal input to propellant, thus more mass flow means lest thermal energy imparted per unit propellant, and thus less exhaust velocity and impulse. Therefore, more thrust for a given core thermal output means less efficiency Ion engines require both ionization energy and acceleration energy on the propellant gas. Ionization energy is fixed for a given mass of propellant (an atomic property of the propellant), The acceleration energy added to the propellant is extremely efficiently transferred into propellant kinetic energy, with little loss to engine heat or propellant thermal energy. A more energetic thruster can get the same mass flow rate moving somewhat faster (slightly more thrust, and improved ISP), or more mass flow at a significantly slower velocity (much more thrust, at the expense of ISP) because of the sunk cost in ionizing the gas, and the greater impact mass flow has on thrust compared to exhaust velocity. TL;DR: You cant have your cake an eat it too, unless you want to invest in a lot of radiators (which have mass, costing total delta V)

But apparently Dres does not... At least that is what the Flat Kerbin Society seems to think. Back to topic The motivation I have in Career is more to accomplish everything, with the financial and research constraints imposed by the Career Mode of playing. Sure a Eve return mission is doable, but to do it sufficiently profitably so you can afford to do it with contracts is the real challenge of career. Career mode is not the purpose of the Game, exploration and building truly Kerbal contraptions is. Career just creates a different experience in the path of sending the Kerbals to the stars. "We will build a surface base on Tylo, not because it is useful, but because it is there." - J.F. Kerman

I've found that a relay in a highly elliptic polar orbit (with the Pe and AP lining up with the pole) gives a very high percentage of coverage of the body, and any of its moons. Putting these around a few planets and moons in the Kerbol system, especially if these are stacked Ra-100, or Snark's modded relay antenna, gives good coverage nearly everywhere. Not necessarily 100%, so planning to ensure capture burns occur within view of Kerbin is a factor in planning. I tend to put these polar relays at Eve and Duna, because they are easy to get to, and quickly add possible paths for comms to go through when the direct path to Kerbin is obstructed BTW, I play extra hard on the comnet, with the only ground station being KSC. The Keosynchonous satellite above KSC is the most important relay I have

Its the Dawn mission to Vesta and Ceres. It spent 100s of days thrusting and coasting on Ion engines, getting a mars gravity assist. It was basically just slowly raising its solar orbit until it matched the target asteroid when it arrived, avoiding the need for large deceleration burns