hey folks quill 18 here and welcome to another episode of our guide to Kerbal Space Program for complete beginners and today we are going to cover getting to orbit and this is by far the trickiest thing for a new player to Kerbal Space Program to do it is the sort of thing that once you've done it a few times it really becomes easy and second nature and almost kind of just routine and trivial especially as you unlock new technologies which will make it a lot easier for you to ship into orbit with lots of fuel left over to do something exciting like go to the moon for example now there's going to be a little bit of theory that we're going to deal with first we're going to start with a little bit of theory about you know what is an orbit and how to get to orbit uh it's going to involve some photoshop type drawing and then we're going to switch back into here to uh build the ship so we're going to do that now if you want to skip it well then feel free but um I think you might find it semi valuable so over here we have a lovely diagram showing curb our planet here and a blue line that represents a path very similar to what we've done before with our launching of our ship and then coming back down at an angle right now we've talked before in the last episode we talked about why it might be bad to go say straight up can I not draw on this Frame hello oh that's not my brush this is the brush there we go uh going straight up and then coming straight down is quite bad because you might come down so fast and not have an air enough air me you but it's even more important to go up at an angle when we're talking about orbits because ultimately getting to space is quite easy we did it before we did it with very little reaching the edge of space over here where the air stops is very easy and then we come right back down the hard part is staying in space because staying in space is not just a matter of going up more or going up even more none of these things help you get to orbit what you have to do ultimately to stay in orbit is to go sideways very fast because what you're trying to do is make it so that instead of falling down here or falling down here or even falling down over here you're trying to make it so that you fall down over here and fall down over here and fall down over here and fall down over here being in orbit does not mean you are not affected by gravity in fact as it turns out that when you are in Space over here you're still being affected by like 99% of the same gravity that you are on the ground for example it's just that if and that and we know that because if we go straight up you know you're going to come down really fast so clearly gravity is still a thing over here but if you go sideways far enough when you fall you will constantly miss the Earth or kbon in this case and that is our goal now you can't just launch in some way that instantly and magically puts to into an orbit you will always launch in a fashion that ends you up with some sort of curve like this it might be it might be a little bit more narrow it might be a little bit wider But ultimately you end up with a curve like this which means that you come back down to the ground at some point what you have to do is you have to do one more maneuver and you're going to be doing this at the top of your Ark Okay the reason is what you have already what you've got here with your launch and then what's going to be your Landing you actually already have a circle it's not an arc it's actually a circle but you can't see all of it because most of the circle is underneath the ground over here um and it's invisible what your goal is to orbit is your goal is to take this circle and make it so big make this circle so big uh hold on I need to make sure that the Anchor Point is set over there to demonstrate properly is so big like this that it pops out the other side of the planet and ends up high enough that the lowest point in the circle right so if we do this then this is the lowest point in the circle this is the highest point this is the lowest point those concepts are going to be very important soon you want the lowest point in your circle to be high enough that it's above 70 km which means it's outside of the atmosphere because if at any point in the circle it goes so low that you hit the air you're going to slow down and eventually you're not going to be in orbit anymore eventually you're going to be landed one way or another because the air will keep slowing you down so our goal is to end up with a circle that is all 70 km above the surface of the ground by the time you are you're all said and done now I will say this the interesting thing is the only reason we have to go up at all how I can't just undo this there we go the only reason you have to go up at all when you take off is just to get out of the air if we were on something like the Moon which has no atmosphere whatsoever right um then the best way for you to reach orbit would actually be to take off completely sideways because that would end you up with a circle that is all most orbital to start off with you are still at whatever your highest point is you're still going to have to do something that will cause the circle to grow into a proper orbit of some kind but if you were on the moon you would only ever have to go high enough so that you're taller you're higher up than any of the mountains so that when you go sideways you don't Smack into a mountain that would be your only goal on carbon it's a little bit more work because we have to go up high enough so that we don't Smack into any air that is our goal over here now one thing uh I think this is is this going to be the last part of our Theory almost one thing we're not going to want to do is go straight up and then Turn and Burn sideways the reason we don't want to do do this is well it's actually quite simple what we don't want is it's the park problem right let me go and do a little demo here let's say you were trying to cross a park okay so this is a park over here you are on the bottom corner of the park and you want to get to the top Corner over here what you could do is you could walk over this way and then walk over that way now if this side of the park is 1 km and this side of the park is 1 km then you will have walked 2 km however if what you do is you cross the park diagonally then you won't walk as far you'll be walking what the square root of two which is I want to say 1.4 question mark something like that but no matter what you will have walked less than 2 km if you just go diagonally and that's exactly what we're trying to do over here if if we go straight up and then burn sideways we are doing that walking around the park instead what we want to do is we want as much as possible to go diagonally over here because what we want to do is minimize that sort of distance and we end up in exactly the same kind of place okay um now we don't want to actually take off from the ground at this angle the reason we don't want to take off from the angle the ground at this angle is twofold first of all if we literally just set our spaceship like sideways ways like that what had happen is we'd sort of probably end up flopping over like that and bad things would happen um it is much easier it is much better to control your spaceship generally speaking to take off straight up until you reach a certain speed and then there's sort of like aerodynamic stability that starts to happen and whatever but that's only a small part of it the real reason you take off with your spaceship mostly pointing upwards is because the air on the ground of kbon is very thick you know at sea level up to about I don't know 10ish km or something like that the air is very very very thick the longer your spaceship spends in that thick thick air the more speed you're going to lose just from aerodynamic drag the air is so thick it slows you down so what we want to do is kind of split the difference in a weird way we know our goal is to go as sideways as possible but we can't go sideways that much right from the start as such we end up taking off straight up and then we start to turn a little bit as the air thins out we turn more and more and more and more there's a couple of different reasons for for for doing this structure you know gravity drag and all kind I I like to really think about it as you go up vertically through the thickest part of the air so you can leave the thick air behind as quickly as possible and then you work your way to turn over to the side because ultimately this is the direction we want to end up in when you're in orbit think about it it when you are in orbit and you've defined your full circle at any point in your orbit what direction are you moving in you're always going to be moving perpendicular to the ground sideways to the ground all right I think that's all the theory there's one more bit I want to talk about going back to our uh little blue circle over here oop not that one this is the blue circle I'm really confused you excellent um one more thing I want to talk about with this circle is the idea that this circle the the path defined by this circle the size of the circle depends on how much energy is into your orbit if you add more energy to your orbit the circle gets bigger if you take energy away from this the circle gets smaller okay keep that idea or if you add more speed to the circle it gets bigger and if you take speed away from the circle it gets smaller and the way we're going to do that is by burning by by lighting our engine and burning our engine in a particular direction to add speed so we're going to take off and we're going to be moving leftwards okay there's going to be a really good reason for that uh I guess I could explain it now if we looking down so this this is the North Pole we are looking down onto the North Pole of the planet which means that um this way is east okay East or from the bottom right East like that if we're looking down on the North Pole of the planet that happens to be the direction that the planet is rotating in the planet it rotates like this which means if we take off going east what it h what happens is the natural rotation of the planet is giving us a Kickstart a really substantial Kickstart it is much much harder and takes a lot more fuel to travel West instead much more work because you have to first cancel out the natural rotation of the planet and then add in that much more just so that you can break even with what happens if you take off towards the east so we are going to take off to the east because it gives us a little bit of a boost okay um yeah so anyway so we're always going to be traveling in this direction over here and on your navball we've talked about that Circle that PR grade marker which is sort of like a yellowy maybe green I see it as a yellow some people call it green um it's the circle like this that's got the two wings that come out the side and the top Circle over there on your navball that Circle represents the direction you're currently moving in therefore the way we add energy to this system is if uh especially right over here ideally here you can do it anywhere actually that's something I should mention in a second okay let's say you're here and you're facing the prograde marker that one over here so your um your orangey uh little like I don't remember exactly the way it's shaped is it like something like this something like that but the orangey thing with the little yellow dot it's more like from the bottom right anyway is in the middle of the prograde marker and you light your engines what you are going to be doing is you're going to be adding energy to this circle and causing it to grow the opposite side if you were to um Point towards your retrograde marker the retrograde marker is the same color as the prograde marker which is that sort of greenish yellow it's the same color like that and it still has the top little like Rudder bit but instead the wings are broken or pointing down that's the way I think of this this is like an airplane with wings which means you're going I think of it that way but if the wings are down if the wings are broken that means you're pointing backwards if you point your ship towards retrograde and you're pointing backwards and then you light your engines what you are doing at that point is you're taking energy away from the system and making your circle smaller now you'll notice that this spot here where you are that's where I keep putting that little um that little Anchor Point here you're growing from out of that you're either shrinking from out of that location or growing from out of that location and that is always true wherever you are now that doesn't change your the that spot in your orbit will not change if that's where you're doing the burn from all you're doing is changing the rest of the orbit in particular you can think of this very much as pushing out the opposite side wherever you are here if you burn prograde you're taking that spot the opposite side of your orbit and pushing it outwards and upwards or if you burn retrograde you are again taking the opposite side of your orbit and bringing it in you're shrinking the circle or lowering that part of your orbit over here at any given point the highest point in your orbit is known as the apoapsis which is marked as an AP and the lowest point is marked is is known as your periapsis which is marked with a PE so um whoops so in this case over here right like this this is the highest point in our orbit this would be the apoapsis this is the lowest point in our orbit which would be the periapsis but if we keep burning here what's going to happen is we keep raising the opposite point and at some point over here suddenly this is now even though we haven't actually changed anything about this spot this is now the lowest part in our orbit because we pushed out the other side so much this becomes the periapsis this becomes the apoapsis it's important to note that at some point these two sides the apoapsis and periapsis they swap this is the lowest point all of a sudden it's the highest point this is the highest point all of a sudden it's the lowest point at some point in doing this they will swap okay with all that I think we've gotten all the sort of orbital mechanics out of the way and we can go ahead and start designing our ship there is one more technical thing that we're going to talk about as we build our ship but uh we we can wait a little bit for that uh we're going to double check mission control again there's many contracts in here I only have one that I have active right now which is to orbit cban that will be my sole goal for this particular mission in fact I'm not even going to be bringing science with us because I want to keep this as dead simple as possible however you will probably want to still continue to acquire much science as you go forward and again you can get science from these extra biomes over here you can get sence from the highlands and the mountains over here if you want and as usual if you spend your sign science to unlock more science you can get more science experiments like the science junr which allows you to keep getting the science over and over also remember that you can repeat any one science experiment in any biome in any different biome so you can do a crew report from the Launchpad one from the runway one from the highlands one from the shores same thing with mystery goo same thing with everything and including lower atmosphere upper atmosphere and finally in space you don't actually have to be in real orbit to do science from space but it is a little bit more convenient because you have a little bit more time to plan things now I have some science I don't know how much you've got maybe you've done exactly the same thing I have therefore you have as much science as I do however I don't know 100% what you've got and I actually want to show how little you need to go into orbit now technically we can go into orbit with what we've got here I've done a test and confirm that you can do it but it's really really tight margins to get to orbit with exactly what we have unlocked so far so I am going to go ahead and unlock one more Tech which is General rocketry over here and the main reason I'm unlocking this is because it will give us a new fuel tank that is simply twice as big as the old fuel tank it's twice the weight twice the capacity it's basically the same we could use two flt1 100 fuel tanks to do the same as a single FLT 200 fuel tank there is no advantage to the ladder except that we currently have a 30p part limit for our spaceship so if we can use fewer parts then it gives us a little bit more room to work it's also going to give me a cool opportunity to talk about the difference between a couple of different engines so I'm going to go ahead and unlock this technology general rocketry which only costs 20 science leaving us with plenty left over in practice I will say this you will probably want your you're getting to orbit is much much much easier if you were to also unlock Advanced rocketry and the reason for that is Advanced rocketry gives you the terrier liquid fuel engine this engine is not very powerful but it's super fuele efficient in space which means you can use this as a final stage in a really efficient way we'll talk about that later but I'm going to only pick up General rocketry and we're going to build our our Orbiter with just this technology all right so we're going to go leave the facility the other thing that can make your life much much easier is if you upgrade your Launchpad if you right click on your Launchpad right now your Launchpad has a weight limit of 18 tons if you were to spend 50,000 Kerbal bucks you could upgrade your Launchpad to give you a maximum weight of 140 so from 18 to 140 you also get a lot more leeway towards your max vessel size uh the other thing that can make your life a little bit easier is upgrading the Vehicle Assembly Building this is considerably more expensive you you might have to run some contracts to be able to guarantee that you have enough money for everything but this will increase your part limit from 30 to 255 still we don't actually need that it makes your life easier it lets you build more powerful vessels which will have an easier time reaching orbit with a bigger margin but we don't actually need that so in the Vehicle Assembly Building we're going to start assembling our ship so we are definitely going to start with the mark1 command pod we are still going to add a parachute to the mark1 command pod so that we can bring jebadiah or Valentina home we are then going to still add a heat shield underneath the command pod and this is everything that's going to be coming home again you may especially if you've upgraded your VAB so you've got a higher part Li you might want to stick some experiments on here especially if there's something that you haven't done but I am not going to be running any science on this Mission we are obviously going to need a decoupler underneath this so that we can still drop off our Ascent stage so go into coupling grab the TR 18 in a stack decoupler and put that down there that ensures that we come home with just this pod and nothing else so now we have to develop our Ascent now we talked about before the idea let me go and just say stick a few fuel tanks on here okay we've talked a little bit about the idea of thrust if we look at our swivel liquid engine over here it has a Thrust at sea level right thrust at sea level of let's call it 170 kons and further more our ship has a weight right now of about 6 tons and the force of gravity on curban just like on Earth is 9.8 m/s although we said we'd round that to 10 Let's Pretend the force of gravity is 10 the weight of this ship is 6 6 * 10 is 60 60 kons is how much gravity is pulling down on our ship gravity is pulling down on our ship with 60 kons our engine is pushing us up at 170 170 is clearly bigger than 60 therefore we will go up now if and again this is a little bit of a repeat before but we're bear with me here if our ship was uh weighed say 17 tons which means gravity was pulling down on us at about a strength of 170 kons which would be about the same as the strength of this liquid fuel engine then clearly we wouldn't go anywhere we'd be breaking even we'd be sort of hovering and nothing would happen uh which would be bad it also wouldn't be very helpful if gravity was only slightly less than our engine because then we'd be spending about 99% of our fuel canceling out gravity and only 1% of it going up so clearly that's not great either we want to make sure that we have a fair bit more thrust than the force of gravity the question is how much right now we have a lot more thrust again we have 170 kons and this ship here would be bet getting pulled down by about 60 so we have um almost a 3: one not quite but almost a 3:1 ratio of the thrust to gravity over here or kind of a a 300% % I guess you would say thrust to mass ratio is that is that enough is it too much is it not enough well this is the sort of thing that you will sort of like develop over time get a sense of um but it is so much here it is so powerful that um while that's good and we will go up quickly it really means we have more room on the ship for more fuel because here's the thing you have to remember your thrust to weight ratio tells you how fast you will accelerate but it doesn't tell you how far you will go imagine the situation where you have two cars they both have a fuel tank that is exactly the same size one of the cars is a insane uh superar with like a V12 engine that goes from 0 to 60 in you know 2.5 seconds and it's being driven by uh Jeremy Clarkson who just wants power right when when when he goes he's going to put the the the pedal to the metal he's going to accelerate really really really really really fast he's going to hit get an insanely high top speed um and he's going to go about 10 Mi and then the car will run out of gas because that giant engine is built for power and rock acceleration but not fuel efficiency whereas next to him is a little hybrid car with a really efficient engine it's only got a top speed of like you know 100 km an hour it can't go very fast at all but it is so fuel efficient that it will be able to cross the entirety of Europe on a single tank of gas even though they had the same fuel tank to start off with that's the difference between an engine that is powerful or one that has very very high thrust and one that is very fuel efficient now we are we are just going to be using one engine throughout over here the swivel but when we're talking about the balance between how much fuel we bring versus thrust that discussion becomes important we need just enough thrust that we move upwards at a comfortable rate and that we don't feel that we're wasting 99% of our fuel canceling out gravity so in practice what you try to Target is probably something like your thrust should um be higher than your the force of gravity by maybe about 25ish per somewhere around there maybe a little bit more than that depending on your shape and different things like that as long as you got at least about 25% more thrust than the weight of your ship you're you're in really really good shape and therefore usually the best way way that you will go further is to add more fuel um there's there's whole discussions about Delta V that is probably outside of scope of this particular tutorial and a lot of the straightup Delta V math mostly comes into play once you're already in orbit but that is going to be our goal we want to go um we want to go and add as much fuel as we can while still feeling comfortable with our oomph and with 170 kons of thrust I'm going to say that we can have a weight of 13 maybe 14 tons and still be happy so if I go and if I click on the top fuel tank I will just rip the whole thing apart if I hold alt and click on the top fuel tank it will copy so let me do that uh and maybe add a little bit more and just to say what do we end up with over here we end up with a ship here we're sitting about 13 tons so like we're kind of getting close to the ballpark over here now there's a slight issue with this ship um in terms of getting to orbit because again getting to orbit is all about your mass managing your weight versus your fuel as we go and we we launch and we start burning fuel what's going to happen these fuel tanks are going to start to empty and empty and empty now as these fuel tanks empty our ship gets lighter because the weight of the fuel is calculated into your ship so our ship will get lighter and we'll go faster and hey that's great but you start to realize by the time we get sort of down here and we only have three fuel tanks of fuel left we are still hauling all these empty fuel tanks to space okay we're still hauling all these things to space and they have weight yeah not as much as when they're full of fuel but they're still heavy and therefore we're spending a ton of our energy hauling empty fuel tanks of space and that feels pretty stupid to me and indeed that is true now adding more engines to a ship let's say I went and did something like this right adding more engines to a ship will give you more thrust you will accelerate faster but quite frequently doing something like this will not let you go further what you're doing here is you're building your superar instead of your really efficient hybrid um I don't know Prius or or whatever and what we're looking for almost always is we're looking for something that gives us more distance more change in velocity actually but let's call it for for this purpose more distance as opposed to just more raw speed so adding more engines is often a bad thing and why is that while it gives you more thrust engines have weight adding an engine these liquid these swivel engines weigh 1.5 tons that is 1.5 tons that is not fuel the only time you want to add more engines is when you need more thrust if you don't have enough thrust to take off from the Launchpad then that's a situation for adding more engines but generally adding more engines means you don't go quite as far uh with caveat for Gravity drag which we're not really going to get into over here but anyway that being said there is a case where adding more engines does make you go further but it might be somewhat counterintuitive what we're going to do is I'm going to grab this fuel tank over here I'm just going to set it aside I'm going to add another swivel engine here then I'm going to go ahead and add another decoupler underneath that and then I'm going to put the stage back in and what have we ended up with here we've added another engine and that is adding an extra 1.5 tons of weight to our ship but I've actually added it in a way that it's not even going to help us on takeoff why would I do that well the reason I'm going to do that is because when we take off we're going to burn with this engine and yeah this engine's going to be working a little bit harder cuz it's got a lift an extra 1.5 tons and you know so that that you know it's a little harder our ship's a little heavier at 14 and 1 12 tons now but at some point when these six fuel tanks are empty we're going to be able to decouple over here and drop this stage away and then we end up with it's the same same swivel engine same stats but this is a swivel engine that's not having to carry a whole bunch of empty fuel tanks to space even though this design adds 1.5 tons of dead weight at takeoff this design will go much further I.E have a bigger change in velocity bigger Delta V this design will go further and therefore will get to orbit a lot better than if we didn't have the extra engine now this is where that Terrier engine I was talking about a minute ago the terrier engine Terrier engine is a really good fit for this stage because it is it's not quite as powerful it's only got a um a Thrust strength of something like 60 kons in fact I think it's only like 18 at the surface the terrier is really bad in at the in the atmosphere but it's not bad in space 60 kons isn't as powerful but once you're sort of in space and in orbit you don't need as much raw thrust as before because you're not even though gravity is still there you're not really working to cancel gravity anymore so having less thrust isn't the problem but the important thing about the terrier is it's really fuel efficient it delivers the thrust that it does with all by using up a lot less fuel than the swivel one does and the terrier is also a lot lighter I think the terrier weighs half a ton instead of 1.5 tons so it again saves a lot of weight and becomes a lot more efficient but you want to make sure the terrier is only ever going to be used in space or maybe the very very high atmosphere where there's very little air anyway otherwise you there's you're not really gaining advantage of it but we don't have access to it so we're going to go with something kind of like this now your balance of fuel tanks at the top versus bottom you you can experiment with different things generally speaking you want less up here than below um and anyway so we're in this kind of situation that's not bad we've only used 16 Parts um we are almost certainly going to want maybe a few basic fins now I'm going to go and I'm going to be yet in this triple symmetry over here three fins is actually all you need to get the entire job done because it doesn't matter I guess I can't actually see the fin that's kind of annoying uh does if whether you're going left right or backwards and forward there's still going to be uh a surface there going to work so three fins just is just as good as four fins and it's slightly lighter and slightly cheaper so that's good now um at this point if we were to take off now I'm just a little bit worried because our ship's a little bit heavier that we might be spending just a little bit too much of our fuel getting ourselves moving in the first place and I would like to give us a little bit more of a kick to take off when you're thinking about wanting a little bit more kick to take off that's where solid rocket boosters Excel solid rocket boosters are a great example of those superar situations they give you a lot of kick for it's really cheap actually um but they don't burn very long right they're just about sort of raw acceleration and then you dismiss them um and I think it would be a great idea for us to kick things off with a hammer solid fuel booster because you can see that its Max thrust is around 200 kons so it's going to be quite good at lifting giving us an initial um an initial go over here now there are a lot of Guides Online that recommend not exceeding somewhere around 300 m/s um at least in the early phases of your takeoff and there there may or may not be uh different arguments to be said about that the reason for it is um in in thick atmosphere once you exceed about 300 m/ second you're going to run into um supersonic forces and lots and lots of Air drag that might slow you down um I'm I'm sort of going off on a tangent here but anyway the point is that the hammer will probably Speedy us up to around there and then sort of like run out of juice and kick off it it should time out really nicely um any anyway yeah I'm sorry about that let's get back to building the ship so let's add another stage over here we're going to want a hammer underneath all this so we're going to need another decoupler and then we're going to go ahead and throw a hammer down there like that excellent oh almost excellent we are actually slightly overweight again because I did not go and upgrade my Launchpad I have a weight limit of 18 tons this ship is going to weigh 18.1 tons so I'm going to go ahead and shave just a little bit of weight off what I'm going to do is grab um one of these fuel tanks let's let me grab this fuel tank over here and I'm just going to replace it with the FLT 100 fuel tank so it's just half the amount of fuel in this top stage it brings us to a weight of I think that's going to be a perfectly happy medium what you don't want is you don't want your Fins Up top because that will cause your ship to flip upside down anyway I'm pretty sure we can use this to get to orbit again if you've got a higher part budget you want to do more add some science add some variety but I'm just going to show this very minimal little ship we want to guarantee that we complete the orbit contract so we're going to take a look at our staging first stage is going to be light this engine um oh we actually do have to fix our engine staging here there we go so first stage is going to be light the SRB then we drop the SRB then we light the next engine then we drop the ascent stage light the Orbiter engine then at some point we drop all the fuel tanks and we parachute back home that's looking okay we're going to make a slight change though to this here's the thing there's going to be when we hit the space bar it's going to drop this stage and then we have to hit the space bar again to light this engine it's kind of bad if during our Ascent we spend any time without any engines burning because um we're going to rely on especially these swivel engines to give us the ability to steer our ship um and in particular if you stop accelerating then it gives the aerodynamic forces a chance to flip your ship out and make it Go in all sorts of directions so we want to avoid not having an engine going and so what we're going to do is this I'm going to take this stage number four which is this engine and I'm going to combine it with the decoupler beneath it so what's going to happen here is when we hit the space bar to drop off the the stage it's going to decouple and instantly light this next engine and we're going to do the same thing with this stage over here we're going to instantly decouple and light this engine in one go so that way we don't have any kind of dead time where the engines aren't burning but other than that I'm pretty happy who's going to be in driver's seat for this I guess we can leave Jeb die in there that's going to be a okay all right let us go so again remember that what we're going to try to do here is we are going to try to go we're going to start by going upward because we're trying to leave the thick thick air as much as quickly as possible but at some point we need to make sure we turn to the east again we want to turn towards the east because that's the way the planet's already rotating so we get a kick start from doing that the general rule of thumb that people use is they tend to accelerate upwards until they hit about 100 m per second over here at which point they uh they manually turn over to about 10° to the east 10° is this uh first sort of circle over here on the navball and in fact one of the things is when you are piloting your ship you spend very little time looking at your ship you spend almost all of your time looking at the navball over here so we are going to be taking off when this hits about 100 m/s we're going to start hitting the D key which is going to turn us towards the east the East is over here see 90° is East this is North is down here south is up here West is over here so we're going to be going towards the east and that's the D key to go over here don't be confused because your camera can be pointing in any way possible but your your WD how come we're slight we're slightly Twisted which is odd huh um but your WD Keys control based on your navball over here so that's stare at your navball and you won't be too confused so we'll be tapping the D key to try to move over to 10° then as we continue to ascend we want to go further and further towards the right I at some point we're gon to end up pointing directly towards the horizon over here but we want to do that over time at what rate do we want to do that in it depends on your ship design it depends on your your thrust it depends on how aerodynamic you are and so on and so forth A good rule of thumb though is you're going to be looking to hit this big circle this big circle over here that's the 45° like 45° angle to the Horizon right so this sort of angle like this you're still Facing East you're still facing a heading of 90 Dees but yeah why is our our ship crooked I don't know maybe it's just cuz we don't have like the support struts over here so oh well it'll be fine probably um but yeah we're going to be going to about 45° when we hit about 15 km or 15,000 M that that tends to be kind of a decent sweet spot as you develop your ships some ships will want to take off more steeply than that the heavier and bigger and less aerodynamic your ship is the more you're going to need to take off vertically um the a more vertical path is ultim Ely less fuel efficient for entering orbit but it's a lot safer and a lot easier so sometimes you'll have to accept a less fuel efficient Ascent in exchange for something that actually gets to space without exploding anyway we are going to go and we're going to turn on the SAS again the hotkey for that is T we're going to set our throttle to maximum we can do that with a zed key so control and shift lets you change your throttle Zed sets Max throttle X sets to zero so we're going to go Full Throttle note that our solid rocket booster that's starting off with it doesn't actually have any throttle control it ignores that but that's going to be important for our next stage we are going to go 100% Full Throttle for the whole thing um again if you're below 10,000 km in the thicker air depending on how aerodynamic your ship is there there's some argument for not exceeding 330 m/s but generally speaking faster is just going to be better because while you might encounter a little bit more aerodynamic drag you'll encounter less gravity drag so in the end you'll probably actually come out ahead when in doubt full thr it's the curbal way anyway without further Ado we're going to go ahead and hit spacebar to launch so with the SAS on Jeb is going to try to keep us pointing the same way we're pointing what I'm going to do though I'm going to use the E key here I'm going to use e to just spin on our our Central axis here just to make it so that the East is to our right again that way I can use the D key I mean we could also spin more so that we could use the W key to go East but that's going to be okay look at our solid fuel it's nearly out as soon as it runs out and hit space bar to Stage excellent so that SRB is gone but it gave us just a little bit of extra kick and I'm happy about it so again as this approaches 100 me/ second I'm going to start delicately tapping the D key to turn towards the right over here notice see the SAS icon when you hit your arrow key SAS is smart enough to sort of cancel and reset itself so jebai tries to keep us pointing straight but he realizes that if we're steering then we have a new straight that let me hit Escape for a second see that yellow circle that our prograde mark that we discussed that is the direction that our ship is traveling in the yellow dot is or the orange dot is the direction we're currently pointing in these are two different things now as we point in One Direction we will be dragging the prograde marker over there because we will be we will start moving in this new Direction but it takes a little while before like that actually gets pushed imagine you're sliding on ice right you can be you know you you push yourself off from the wall on the ice you're moving in One Direction if you rotate yourself so that you're facing to the side that's not going to change which direction you're moving in you're going to keep sliding in the same original Direction same thing happens here until you know the engine pushes us further to the side you want to avoid going too far outside of this yellow circle because it means you will be pointing quite differently from the direction you're moving in and that causes the air to hit your ship from the side all of a sudden which could cause your ship to flip out or even break apart so you you want to avoid going too far outside of the yellow circle depending on your ship design sometimes you you desperately need to stay inside the yellow circle and some ships can afford to go a fair bit outside the yellow circle and still be safe it depends on your design it also depends a lot on where you are in the atmosphere right now we're in the thick thick thick air so it's very important to stay in that yellow circle when we get into the upper atmosphere which is very thin then really we can pretty much ignore the yellow circle if we need to because there's not enough air to cause a problem so we're going to keep ascending and again I'm going to try to stick on the right hand side of the circle and again my general sort of idea is to hit this 45° um angle when we get to about 15,000 km because that tends to describe the right kind of turn um you'll also hear the term gravity turn applied here which is really what we're doing now in a really sweet perfect gravity turn we actually don't have to manually steer our ship at all it'll actually end up sort of rotating like this um very gradually and naturally but we're not quite there so that's okay so 11 km 12 km I'm just tapping the D key a little bit and I'm trying to encourage the prade mar marker to nudge over to 15K I'm going to just steer up a little bit here just to try to get us right on the East marker again and that's pretty sweet look at that we're pretty much where I kind of want to be that's going to be excellent so we're going to keep that going now you don't have to be in this view at all the only time you have to be in this view actually is when you need to Stage the rest of the time it's often going to be better to be in the map view which is what we're going to switch to in a second which use the m key to do that still I'm going to stay in this view just long enough to finish this first descent phase you can see we're almost out of liquid fuel here so I'm going to keep doing this now we're past 15K so I'm okay with going a little bit more sideways I'm just going to stop controlling anything for now going to wait for this liquid fuel to go and there we go we'll stage now I'm going to go into the map view over here and I'm going hit Escape for a second so by hitting M we go to the map from this screen you can still steer your ship however you can only steer the ship if you expand the navball which is down here okay you need to expand this navball and all of a sudden you can steer the ship from this view which is exactly what we're going to do so I'm going to hit escape to to close this little pause menu there we go expand the navball and so I can still steer the ship over here and I keep it pointing mostly prograde now if we turn the view so we can use the right Mouse button to turn over here and hit Escape you want to look down onto the North Pole okay we're looking down onto the North Pole and our ship is going east which is to the left your this is you should get used to it this is your default view that you're mostly going to look at for your orbits you're going to look down onto the North Pole and we're looking to enter orbit counterclockwise okay we're taking off to the left or we're rotating in a counterclockwise direction we took off somewhere over here we are now here and this is the highest point that we're going to reach right now and we want to check what the height of this highest point is and we're going to find that out by mousing over AP okay I can't do it now because this menu is open but if we Mouse over AP we're going to find our highest point how high do we want to go we want to go so that the the highest point in our path is above 70 km 70 km is the height of the atmosphere we can't be orbital if we're still in the air because the air will slow us down and bring us down to the ground so we have to be above 70 so I'm going to hit Escape I'm going to Mouse over oh we we are we're well above 70 o That's not idea apparently I spent a little too long talking okay that's fine the reason I'm sort of a little uh um you know not happy about this is because the we have used extra fuel raising our app wapes the highest point in this Arc we have spent extra fuel raising this up and this is fuel that we want to use to go sideways we only need to be above 70 and we're at 95 so we spent extra fuel doing that it's not it's probably not the end of the world but yeah so I'm just I just killed the the gas and we're just going to Coast at this point literally just coasting uh we're in the thin enough atmosphere we're at 70 or we're we're sorry we're closing in on 70 um kilm over here I think we can Mouse over our ship as well yeah so we can see our current altitude the second we hit 70 we are going to be in space now of course we've done this before so we are now in space so there's no more air so it doesn't matter where we're facing but let's take a look how much fuel we've got left I've got a fair amount of fuel left hopefully you do as well hey if you did it better than I did your app wsis will be at something like maybe 75 you know you get you get a little bit of a margin that's okay as long as it's over 70 you're good if you sent this over 100 then it's possibility if you spent a little bit too much fuel going up remember a lot of our fuel has to be spent going sideways now you might have an arc that's a little bit more sort of steep that means you didn't go sideways enough and that means it might be a little bit more work to circularize sometimes you end up in the stage and you have really a flat shallow Arc and that's really sexy because that means you're going to have to spend very little fuel Circ izing so remember our diagram this this circle this Arc kind of well it's a ellipses not a circle but it describes something that still goes inside the planet and what we want to do is we want to um at the this point here we want to burn prograde to add more energy to our Circle we want to Igan our Circle so that it rounds itself out and in particular pokes out the other side of the planet so we describe a nice round orbit this is called circularizing we want to do it at the apoapsis because remember when you are adding energy to the system by burning prograde what you're really doing is you're pushing the opposite side of the circle higher up so if we were to burn prograde over here what would what would happen Well we'd be pushing the opposite side of the circle would be here up and we could technically go into orbit by doing something like that but the problem is you're pushing the opposite side of the circle up meanwhile this bulge over here is going to look like this which means your app waps is going to going to be high which means we've actually spent a bunch of fuel raising the apoapsis and ending up with a really wonky non-circular orbit the fact that it's not circular isn't actually a problem except that it's not fuel efficient because we did way more work rising out the bulgy Parts than we needed to if you have a nice circular orbit it means there's no bulge that represents wasted fuel so The Sweet Spot to do it is at the apoapsis which is the highest point in our current quote unquote orbit which is going to mean we're going to be raising what is current the lowest point in our orbit up and end up with something as circular as possible so we want to wait until we're as close to the acsis as possible and then we want to burn prograde which is this marker over here the yellow circle with the two wings that come out of the side now as we approach so we can point to this prograde marker but this prograde marker represent the direction we're moving in and right now we're moving slightly up when we get here let me pause again because we're getting quite close when we get here we're going to be moving completely sideways so your prograde marker is actually going to drift and change depending on what part of this Arc you're in because obviously here the prograde is pointing up here the prog grade's pointing down so clearly the prograde marker moves around a bit how do we do this well most of your guides and especially later when you get maneuver nodes you can time this out properly we want to we need to dump a certain amount of energy into our quote unquote orbit at the apoapsis so that the periapsis pops out the other side and if we could we would dump all that energy instantly however that's not actually possible with our engine design as such we're going to have to burn our engine for several seconds to get the job done and ideally we'd like to burn about half the time before the apoapsis and half the time afterwards because all the math will work out to be super efficient that's not really feasible in this particular situation because we're mostly going to be guessing so I'm going to give you a cool rule of thumb if you point prograde and then you light your engine if the app wapis starts to move away from you that means you started your burn too early and it means you're going to be spending too much energy raising your apoapsis as opposed to just circularizing so if we start a burn and the apoapsis moves away from us we are then going to stop the burn wait another couple seconds and try again so I'm going to start the burn apoapsis move not too quickly but it's definitely moving away from us so I'm going to stop and so instead of going to full burn what I'm going to do is I'm going to hold shift and just bring my throttle up slowly and oh it's still moving away from us so I'm just going to hit cancel and wait because it's more efficient if you avoid pushing the apoapsis away from you inevitably at some point it will move away but that's going to be all right so let's try this again I'm just going to hold shift to slowly throttle up and there we go so we sort of Frozen it doesn't look like the apoapsis is getting closer to us it's not really getting away from us either maybe getting away from us a little bit but that's okay I'm going to just turn again to make sure I'm facing more correctly prograde over here and try to keep that in the appap is moving towards us which is I mean is good the only problem is is it it moving towards us too quickly because if it passes us and we still have a long way to go to circularise it's not great so I'm just going to throttle up and just kind of try to freeze it there we go about a fixed distance now shifting away from us again it will move a little bit that's not the end of the world I'll Throttle Down a little try to keep it there meanwhile if we take a look look at our path look at our path what's happening it's getting wider and wider and wider and it's some point it's going to poke out the opposite side and we'll actually see the periapsis marker it'll say PE there it is and at some point what's going to happen see the apoapsis moving away in the periapsis at some point they're going to want to swap we're going to say stop right around there they're going to swap because of course at some point if we keep burning here and we keep pushing the opposite side up at some point inevitably the opposite side of our orbit becomes the new highest point so when these two are swapping that should be when we are at about the most circular we can be let's check our app wsis is now 105 km so we have pushed it up a little a little bit more but I think we're okay meanwhile our paropsis is at 90 km so it's not exactly circular they're a little bit off but that's pretty good I mean if you're just eyeballing that that kind of looks like a circle to me I think we can be relatively proud of that um and most importantly the lowest point in their orbit which is always the periapsis is above 70 by being above 70 that means it's not in the atmosphere which means we have achieved orbit and we can actually verify that by checking our alerts over here here uh we can find out we've got a milestone that we entered orbit and we've completed our contracts over here getting a whole bunch of Kerbal buck and some extra science as a reward even though we didn't bring any science with us we got some bonus science which is great because this orbit does not touch the atmosphere it is a stable orbit jebadiah in his little spaceship over here will be an orbit around the planet forever unless we do something so happens we have just a little bit of fuel left over that's quite lucky for jebba out otherwise I hope he brought enough snacks uh because he would not be coming home but we have just a little bit of fuel left and that's going to be all it takes for us to get jebadiah home in fact we won't even need this much fuel how do we get jebadiah home well your first instinct might be hey let's point the ship at the planet which we can totally do I mean you can just eyeball it here and point the ship to the planet at some point okay so you're pointing at the planet see this blue marker over here with the arrows pointing in it turns out this is the I think it's called the anti- radial doesn't matter this is the icon that says hey you're pointing at the thing that you're orbiting right now and on the opposite side of the navball for example there's a blue circle with the arrows pointing out hey you're pointing away from the thing that you're orbiting there happens to be two purple markers perpendicular to this as well this is the there's the normal and anti-norm these pinkish purple markers but we can ignore them for now now technically if you pointed towards the planet and burned technically this Pro this would get you home but not in a very efficient way the radial and anti- radial Burns what they do we can go into Photoshop for a second again what they do is uh let me go and uh do this oops come on do this and then do this so that we've got our orbit if we were to go to burn radial or anti- radial what you're doing is you're twisting your orbit around wherever you are so again we're here okay we are here if we were to burn radial or anti- radial you actually end up doing this so if burn towards the planet yeah we will go ahead and and we will hit the planet somewhere over here by burning towards the planet we will hit the planet over here but what you're really doing is you're just literally you're pivoting your orbit around whatever Point you're at which is kind of a neat thing and it's actually a tool you can use for various stuff but isn't what we're looking to do right now because moving your entire orbit over this way actually takes a fair amount of fuel this is hard work to do that instead the best way to come home the best way to come home is to do the opposite of what we just did we just added energy into the system to raise the opposite side of our orbit if we take energy away from the system it'll shrink the circle and lower the opposite side of the orbit and as it turns out these movements here they really take very little fuel to do this so we want to drop we want to shrink this circle until the lowest point of our orbit is is within the atmosphere cuz if that happens that means that at some point we're going to hit the air it's going to slow us down and if this point in our circle is say even like 30 km above the surface so it's not even touching the ground but even at 30 km above the surface we're going to be hitting such we're going to enter the atmosphere probably somewhere around here hit some air slow down we'll actually end up Landing somewhere here in the end just because of how much the air slows us down so we don't have to have the circle go inside the planet we just have to have it go inside the atmosphere so that's going to be our goal and as it turns out this is a really cheap thing to do fuel-wise now where do we want to do this the most efficient thing to do if we want to lower our orbit right we want have make sure that our orbit is low enough that it's inside the atmosphere so then it makes sense that we should lower the already lowest part of our orbit right if our orbit looked like this we would not want to lower this part down to here because look at all the distance that would be inefficient in instead in this situation it would be much better if we lowered this part over here down because it would take a lot less work to lower this already low part to slightly lower and that's exactly what we're going to do we're going to take the lowest part in our orbit and drop it down until it's within the atmosphere and the lowest part of our orbit is always opposite the highest part of our orbit so we want to be at the apoapsis and we want to burn retrograde to shrink our Circle so let's go ahead and do that so if we take a look at where we are the lowest pointer orbit is the periapsis that's what we want to drop so at the opposite point of our orbit we want to go and remove energy remove velocity from our orbit so that our orbit shrinks and it will shrink will be anchored over here you never you sort of never change where you are right by making a burn by by lighting your engines you don't change where you are now you just change where you're going to be in the future so we're going to go at the apoapsis we're we're going to burn retrograde so we're going to find the retrograde marker which is the yellowish greenish circle with the downwards Wings because we're slowing down so if we do this we are now facing in the opposite direction of movement you can see that right we're moving that way you can see by by the curban beneath us and we're pointing away from that so our engine is pointing in the direction that we're facing which means if we light the engine we're going to be slowing down and we're just going to wait until we reach the apoapsis now I'm going to do a little time warp here cuz I'm impatient before you time War you should really quick save I'm going to hit F5 to quick save cuz it's very easy to accidentally Time Warp too long and have everything go Bonkers so then if that happens you can hold the F9 key down to reload from your quick save so I'm just going to go ahead and Time Warp a little bit so I'm hitting the period key to accelerate time and then when we get closer to the apoapsis I'm going to hit the comma key to slow down the time warp so that just sped things up if you're impatient like me so I'm going to call that close enough to the app wsis we're not going to be exact that's okay I'm going to open up the the navball frame I'm once again going to go and just turn so that we are facing exactly retrograde and then I'm going to light the engine and it's going to be dropping the opposite side of our orbit and all we care about if you right click on this it'll stay open so you don't have to worry about leaving your mouse there all we want that to do is to drop so it's less than 70 less than 70 means we'll hit the air we'll come home at some point in practice put it between 30 and 20 right 20 to 30 that's going to be a good range to guarantee that you hit some good thick air and you slow down in sort of an attractive fashion so retrograde and I'm going to hit Zed to accelerate whoa that's really fast actually I'm just going to hit a few shifts and wait for that come down there we go 23 km sounds great now we could keep burning retrograde here I mean we use like a thimble of fuel that was really cheap we could burn the rest of our fuel bring our paropsis down lower but we don't want to and the reason is this while it would be perfectly fine if we dropped it to the point where our path intersected Kerbal you know over here and like actually hit the ground over here um there's no reason to do it when we did in the last video for our return we wanted to come through with as much air as possible between us and the ground this ensures lots of air between us and the ground we're still going to land but this gives us maximum air that's not as important for the return from this orbit here cuz we're not actually going that fast well we're going at 21,000 or 2100 m/ second here but if we're coming back from the moon or even from outside of the local system here like you come back from another planet you'll be coming back really really really fast and you really want a lot of air between you and the ground so this tends to be how you return the funny thing is despite the fact that this is the lowest point in our orbit it is very likely that we will land maybe here maybe even in the ocean over here because again we're going to be hitting the air here and slowing down so we are inevitably going to be re-entering the atmosphere our altitude is dropping here we don't need these fuel tanks anymore we don't want them to burn up and explode and kill us so we're going to go hit space bar to Stage like that once again I'm going to go and Time Warp by hitting the period key on the keyboard I'm going to Time Warp like all the way to time 50 which is our limit right now as soon as we enter the atmosphere it will automatically cancel Time Warp for us there it is what I want to make sure to do now is to point our heat shield into the air and we do that if we're P if we're want to past if we want to place our butt into the direction we're moving in that means we need to face retrograde retrograde means our nose is facing away from our direction of movement or our butt is facing into the direction of movement which means the um the hot hot air that we're soon going to be hitting is going to be hitting our heat shield because the Shipe is actually aerodynamically stable we can actually toggle off the SAS and it should automatically keep us facing retrogade there'll be a little bit of wobble at first here because it's quite thin air so it has a hard time locking in super hard but as we get into thicker thicker air it'll really steady up in that orientation if your your uh Center of mass is a little bit off if you have some extra bits and Bobs on here that might be adding wonky aerodynamic uh drag you might be forced to leave SAS on and just manually keep yourself facing retrograde because your ship might want to um might drift away from it just uncontrollably but here we're good turning off the SAS I'm just going to go ahead and Time Warp uh again you should quick save before you Time Warp but we've got one not that far away so we're going to go ahead and just let this uh capsule return in and if we hit M to go to the map we can actually see our paropsis dropping over here because we're being slowed down by the air it's dropping it's dropping it's dropping it's now inside the planet and we're going to keep seeing the path and again I suspect we'll probably end up Landing maybe in the ocean at this point actually even though our lowest point was over here we're just being slowed down so much by the air yeah we're definitely going to splash down in the water and that's fine so flame effects are going on speed is being burned off our um heat shield our our blader is being burned off that's exactly what it's supposed to do it lets itself burn away so that the heat doesn't accumulate in the Pod but at some point probably quite soon we're going to stop seeing heat effects if we keep an eye on our parachute it's red right now which means it would be dangerous to open up the the parachute it'll turn yellow for a moment when it's risky and then it'll turn there we go white when it is perfectly fine for you to open open your parachute I'm going to wait a little bit longer because it'll take us a long time to actually hit the water if we open the parachute now I'm going to say now is going to be fine so we're going to do that the parachute does not fully deploy until you're under 1,000 M from the surface which is now excellent and I'm going to ahead and cancel the time warp and there we go now we're going to land at a nice gentle 6 m/ second that is actually fine but if for some reason you're ever descending and it's slightly too fast you're worried you might hit a little too hard one of the things you can do is shed a little bit of extra weight here if you right click on the heat shield you can jettison the heat shield we don't need it anymore and it's just heavy so the parachute is you know being pulled down a little bit harder so if we go and jettison the heat shield you can see our surface speed now drops quite a bit so instead of dropping are landing around 6 m/ second we drop at about 5 m/ Second so Jeb is going to be slightly more comfortable I'm going to go ahead and time warp again and there we go splash down boom and just like that we have returned home from orbit we can recover our vessel and congratulations you have just achieved one of the most difficult things to do as a newcomer to Kerbal Space Program orbit is not easy oh we get some bonus signs for returning from orbit even though we ran no science experiments we actually got a fair bit in there hey it's night time by the way if you're not if you're not happy with the time of day uh you can you can use the time warp controls over here you can also use this handy dandy button to warp to the next morning which is quite nice there we go in case you don't like launching in the darkness so what next next for you would be to go to the Moon almost certainly there's going to be a contract here to explore the moon this contract simply requires you to do a flyby of the Moon not Landing just fly by it this is not going to be covered by this tutorial system over here um in well maybe maybe in the future I'll make a follow-up video for the moon but in practice if you follow any of the let's plays at this point you should be able to follow along it you will get great instructions for how to do a fly of the Moon in fact Landings of the Moon and so on and so forth feel free to explore these different contracts at this point to try to raise some money and if the contract seem kind of poopy um then go ahead and feel free to decline a contract and you should get a new list of contracts from time to time as you do things so again testing the hammer solid fuel booster while orbiting curban this would be quite tricky does offer a lot of money but we'd be hard we're going to decline that and instead you know some new contracts kind of come in um this is a good way to rate money if you need more science then again you can do science at any different biomes each one of these locations at the Kerbal Space Program counts as a different biome if you go and unlock some Wheels which happens first at Aviation over here you can make yourself kind of a little car right just a fuel tank an engine and some wheels and all of a sudden you've got a car that you can drive around on the surface of kerban and stick some science experiments on there and then drive it around the Kerbal Space Center keep in mind cars are really good way to kill your kerbals because it's really easy to go too fast and flip them over so do be uh do be a little careful with your driving and also uh don't make go ahead and make liberal use of the quick save over here so money will let you upgrade your stations science will let you unlock more parts um and I don't know I think that's it for this this really simple little tutorial hopefully you found it of good value and again you can find more activities by watching Let's Plays which I feel that uh you all the tools to do that at this point thanks for watching folks and I'll see you next time