Search the Community

This is an in-depth tutorial, but still directed to beginner-intermediate players, on how to do a proper launch and gravity turn with the new aerodynamic model introduced as of version 1.0. This tutorial works for versions 1.0 to 1.3. More than giving a script or set of instructions, my goal with this tutorial is for you to gain an understanding of the factors that affect your rocket's behavior during launch, so that you can apply it to any rocket you fly. For that, you'll need to go through the entire post, but I'm also including a TLDR as a "cheat sheet": TL;DR (courtesy of @kBob) 1. Turn ON SAS and set throttle to give TWR of ~1.5. 2. Launch! 3. When your speed reaches 50 m/s, perform a pitch over maneuver (tip towards the East until pointing between 5° to 10°). 4. When SAS stabilizes (i.e. the control input arrows on the bottom left are all centered), turn it OFF. Avoid control inputs and use only throttle to control your gravity turn (throttle up to turn slower, throttle down to turn faster). 5. When your altitude reaches ~40 km, turn SAS ON. Start pitching down manually towards the horizon and adjust throttle to keep your Ap around 45 seconds in front of you. 6. When your Ap reaches the desired altitude, cut your engines, coast to Ap and circularize. ========================================================================================== General Notes on Gravity Turn You all probably know by this point that to get into orbit you need to go up, above the atmosphere, but you also need to go sideways (i.e. horizontally) very fast. To do this, we could launch straight up until we're out of the atmosphere, then point sideways and accelerate to orbital speed. But that would be very inefficient. We want to launch in a way that we gradually turn sideways while we ascend. This is called a gravity turn. The best way is to do a real gravity turn; that is, a turn caused by gravity and aerodynamic forces, rather than one achieved by actively turning the rocket. It is important to keep this in mind. Design Items Before even launching, you need to take these design items into consideration when building your rocket: TWR: Your thrust-to-weight ratio (TWR) at launch should be relatively low, around 1.5. A higher TWR at the beginning of the launch makes it harder for your rocket to turn naturally, as gravity will have less influence on its trajectory, making it fly straight and screwing up your gravity turn. Keep in mind that drag losses are almost negligible in the new aero, unless your rocket is shaped like a brick or you are going extremely fast in the lower atmosphere. Thus, a slightly higher TWR of around ~2.0 in theory is more efficient, but only if the launch profile is flown correctly. The drawback is it makes your rocket less forgiving in terms of control during ascent, and it shortnes your widnow to make a pitch-over maneuver. What usually ends up happening is that you have to force the gravity turn manually, which does generate significant drag (because you expose the sides of your rocket to the airstream anytime you deviate from your prograde vector), and causes steering losses (Dv wasted on changing direction rather than gaining velocity). This reduces overall efficiency and defeats the purpose of having a higher TWR to begin with. A higher TWR also causes increased stress to the craft, inducing wobble and risking a RUD, especially when trying to maneuver. You may experience heating issues too. For these reasons, in my experience, a TWR of ~1.5 is a good sweet spot between efficiency and controllability of the rocket. Smaller and lighter rockets handle higher TWR's better than big and heavy ones and each craft will have its own sweet spot; you are encouraged to experiment. If you find your TWR at launch is too high, either use a smaller engine or just throttle down, and vice versa. As a final note, all rockets will have their TWR go up as the launch progresses due to shedding weight by burning fuel. This is normal and you should manage by reducing throttle throughout the ascent as needed (more on this below). You can check your TWR with the Kerbal Engineering Redux mod (KER) or with MechJeb, or if you're running a stock game, the G Force meter roughly doubles as a TWR meter (if the G Force meter is pointing at 1 your TWR is roughly 1, and so on). Aerodynamic Stability: You want your rocket to be aerodynamically stable. That means that it will have a natural tendency to fly straight, instead of, say, sideways. Any object that flies through the atmosphere will naturally orient itself with its center of mass (COM) facing forwards relative to its trajectory and its center of drag (COD) facing backwards. You can see this in darts, arrows, badminton cocks, etc. Similarly, you will want to have your rocket's COM in front of your COD. To ensure this, add 3 or 4 winglets or wing surfaces with radial symmetry at the base of the rocket, and if possible cover your payload in a fairing to make it more streamlined. If your rocket insists on flipping, you need to add more/larger wings at the bottom. If that still doesn't fix it, it means your COM is shifting back too much as fuel is burnt. The heaviest part of a rocket in KSP is usually the main ascent engine(s), so the COM will tend to move back as fuel is spent. The easiest way to fix this is to add a small fuel tank at the top of the stage that's experiencing the problem and lock the tank in the VAB (right click on the tank and select the green arrows for both fuel and oxidizer). This fuel tank will act as ballast keeping your COM forward. You can unlock it manually in flight when the rest of the stage's fuel is gone so as to not waste it, and then stage as normal. Ascent Profile Once you've implemented the above design items, follow these steps for your ascent: 1. Turn on SAS and set your throttle to whatever will give you a TWR of ~1.5. 2. Launch! 2. As soon as your speed hits 50 m/s, perform a pitch-over maneuver to begin your gravity turn. To do this, tip your rocket towards the East slightly, until it is pointing between 5° to 10°. Don't start pitching over before your speed is ~50 m/s, otherwise you will likely find yourself horizontal within a few seconds, as your winglets won't be biting into the air hard enough to provide stability. The higher your thrust, the more you need to pitch over initially, because higher thrust makes the rocket want to go straight. If you're using a TWR higher than 1.5, your pitch-over should be to at least 10°. 3. As soon as your SAS stabilizes (i.e. the control input arrows on the bottom left are all centered) turn off the SAS. Watch closely for this moment, as you will have only a small window of a few seconds at most before the SAS starts trying to resist the gravity turn. Turning SAS off while it's trying to steer will cause your rocket to become unstable and lose its heading or possibly break up. You should be done with your pitch-over maneuver and have your SAS turned off by the time your velocity is around 100m/s. If you take too long and your rocket is going too fast by the time you're done, it won't want to continue turning (fast rockets like to go straight, remember?) and you'll have to force the turn manually, which is inefficient and causes stress on your craft. As mentioned above, a gravity turn should happen on its own and not as a result of control input. For particularly unwieldy rockets, you can lock SAS to prograde instead of turning it off during this phase. However, stock SAS is far from perfect and it's best to let gravity and aerodynamic forces do the steering for you. If you do use SAS, be sure to disable it before you hit 35 km to avoid you craft from jolting down suddenly when the navball automatically switches to orbit mode, which happens at around 35 km. 4. Enjoy the view while your prograde marker gradually sinks towards the horizon; your rocket will follow on its own thanks to gravity and aerodynamic forces. Try to avoid control inputs during this phase (i.e. no AWSD), just let it fly. If you need to make adjustments, use throttle. Remember, lower thrust means the rocket turns more, higher thrust makes it want to go straight. At about 10 km altitude, you should be pointing roughly to 45° and your speed should be around 500 m/s. If at 10 km altitude you're still pointing above 45°, your TWR was too high and you went too fast and/or your pitch-over maneuver was too gentle. Next time throttle down more or make a more aggressive pitch-over maneuver. On the other hand, if you're pointing below 45° at 10 km, you went too slow and/or your pitch-over maneuver was too aggressive. Next time use higher thrust or do a gentler pitch-over maneuver. If your rocket flips on its end at any point, it's not aerodynamically stable enough. See above under "Aerodynamic Stability" for possible solutions. 5. At around 40 km altitude, turn SAS back on and start steering manually; use pitch and throttle to keep your Ap around 45 seconds in front of you. Any time you're burning above the horizon, you're wasting part of your thrust to gravity instead of gaining horizontal speed; this is called gravity losses or gravity drag. In the initial stages of the launch, you can't help incurring gravity loses because you need to gain vertical speed to get out of the atmosphere. The atmosphere also means you can't steer away from the prograde vector without inducing aerodynamic drag, steering losses and/or destabilizing your rocket. However, by the time you get to ~ 40 km, you'll have enough vertical speed and the atmosphere will become negligible. Thus, at this point you want to begin gradually pitching down towards the horizon. During this phase, you will also start adjusting your time to Ap. It's most efficient to perform your orbital insertion burn right at Ap, so you want to keep it "hovering" only a few seconds in front of you. Of course, you don't want to it to get too close either, otherwise you risk passing it and falling back down into the atmosphere. A time to Ap of ~45 seconds is a good rule of thumb to balance safety and efficiency. To control your time to Ap, use pitch and throttle. If your time to Ap is more than 45 sec, throttle down a bit and point more horizontal, and vice versa. Avoid pitching below the horizon. Continue adjusting pitch and throttle until your Ap reaches your desired altitude, at which point you can cut your engines, coast to Ap and circularize. Note that as you approach orbital speed, there will be a point when your Ap will begin shooting away even if pointing straight at the horizon and no matter how much you throttle down (unless you cut the engines of course). If you reach this point, just let it go until engine cutoff; any efficiency gains from keeping your Ap near you will be negligible by then. Advanced Mode Try doing the ascent and orbital insertion in a continuous burn. This is the most efficient profile (citation needed) and it's extremely satisfying. Easier said than done, though. To pull it off, you need to allow your time to Ap to creep closer and closer during steps 4 and 5, while not allowing it to get higher than your intended orbital altitude. You do this by reducing throttle and lowering your pitch in a more aggressive manner. The closer you are to orbital velocity, the closer you can allow yourself to get to your Ap. You want to hit orbital velocity exactly at Ap. There will be much trial and error and the exact procedure will vary from rocket to rocket, but give it a try!

I ask those with experience in real solar system how the gravity turn goes. in the stock game, you generally want to turn very fast, starting already around 50 m/s, being down at a 45° angle already at 500 m/s. that because in stock you orbit at 2200 m/s, you want to be horizontal at that speed. in real solar system, at 2200 m/s you still miss over 5 km/s to orbit. I had experiences where I did start angling down early, and I had to pull up later. on the other hand, I am now trying to go straight up until around 15 km altitude, and while this enables a proper gravity turn afterwards, going straight up at 700 m/s doesn't feel right. it can't be optimized, can it? and orbital launches in rss last way too long for me to want to go by trial and error. any good tip on when I should start turning?

I'm attempting to build a massive SSTO rocket but when I attempt to start turning in the air my rocket instantly explodes. I'm using part clipping to get the diameter of the rocket smaller but from what I understood that shouldnt affect the physics of the craft. The flight log says that there was a structural linkage failure between two adapters high up on the rocket in a random spot. If it helps I'm using vector engines attached to an engine plate onto a 5m fuel tank.

I designed a basic rocket and it performed quite well. It even got into the gravity turn without need of steering input. Then I decided to try to explore the limits o the design a bit and among other thing I wanted to look how it behaved without the basic fins. To my surprise, it don't flip but also don't get into the gravity turn by itself. Despite being launched with more tilt than the original craft it went up. And is not that it didn't turn at all, rather it osculated slightly west-east, as if there was some sort of self-righting mechanism. Just I have no idea of what it might be. There is the craft file if anyone is interested in trying it for himself: Strange and a picture

I have seen some guides say throttle down if it the turn goes too fast, but in someone else says no, do 5 degree force turn for adjustment. But which is actually better?

hi, after several launches Gravity Turn gave me this values: This is the probes launcher: These are two videos that show the same thing: as soon as the first stage detaches, the launcher no longer can maintain the alignment with the prograde direction and for some seconds it pull up its nose in a non-aerodynamic fly. I just would like to understand why of this behavior? have any ideas? I don't know... too long fairing? Full launch: https://www.dropbox.com/s/69kj8n4zjilhxyy/launch.mkv?dl=0 Short launch: https://www.dropbox.com/s/ey9wt7hvsla5qcz/short launch.mkv?dl=0 Screenshot: (look navball aligment)

Hello, Yesterday I was trying to launch with a proper gravity turn. My vehicle was a mk2 shuttle with an external tank and its TWR was a little low after the separation of SRB’s (about 0.8-0.9). However I noticed that the AP continued to rise even with such a low TWR. I then continued with a launch profile where I tried to keep the AP within a minute away. I had the TWR in about 0.9-1.1 during much of the ascent. All the time my AP was rising. I assume this is because as I increase my horizontal speed the ground “falls” away from me even if my TWR is below 1.0. Is this the way it works? Anyway, I got a stable orbit around 95km but I was wondering that such a low TWR during a ascent is probably not the most efficient way of launching (previous test run with about 1.5 TWR gave a 250km orbit). What kind of ratio should I aim at after the separation of SRB’s? Even if it wasn’t the most efficient profile it was a real pleasure getting a nice orbit with such a low TWR! And if nothing else, it had me cracking my brain for the rest of the evening, so all in all a massive success!

I've been playing a bit of RP0 lately, and I am having a bit of trouble figuring out how quickly I should make my gravity turns. I especially have trouble with low TWR upper stages, such as ones using an RL10. Does anyone have a heuristic for doing gravity turns that could apply here?

So, when I look at the Delta-V chart, going into LKO must "use" 3400 m/s of Delta-V. But me when I get to orbit I "use" approximately I use at least 4200 m/s of Delta-V. I know it's quite impossible to do as the Delta-V chart say but I find that I use too much Delta-V for LKO and I think that the problem is from my gravity turn. So do you have some tips to do an efficient gravity turn ? Thank you Fly safe

I finally managed to build a reasonable craft for Eve Space Program that can get to Eve orbit with about 1300-1400 m/s dV left. In career mode, with only Tier 3 and 4 parts. Craft file here, uses OhioBob's Eve Optimized Engines. After several attempts, my best effort is in this video here. The biggest challenges of the current incarnation of the Eve Space Program mod are the lack of biomes outside of the KSC, and the distance of most survey contracts; the KSC is a quarter of a world away from where the game puts those surveys. This leaves part tests, science grinding around KSC, and a full fundraising campaign strategy (25% of reputation going to funds) to pay for building upgrades. Otherwise I'd be using a lot better parts for this craft. As it stands, the only remaining source of decent science is Gilly, and I can't reach that and get back on 1400 m/s. I didn't do any dV math really; just tried plotting to Gilly's orbit needing 1425 or so m/s, and came up short just by 20+ m/s. That being said, I remember someone saying that ascending from Eve's surface to orbit needs a launch profile that goes straight up for a large part of the ascent, then starts the gravity turn very high up. With this craft I find I can start my turn just around 20 km, and also before staging away the last of the Adam engines and going to my first non-EoE; the Swivel, close to 35-40 km. Then some careful throttling and I can get to about 1400 m/s orbit speed before staging away the Swivel and going to my Terrier, finally closing my orbit with maybe 2/5th of my fuel. What would be a better ascent profile for launching into Eve orbit? Where to start turning away from vertical? At what altitude and at what speed should I have a pitch of 45 degrees? If you try this craft, note that Eve Space Program's launch pad is only at 450 m altitude, and I'm using tank priorities and decoupler fuel crossfeed to use a hybrid of onion staging and asparagus staging, so watch the tank levels on ascent. [Update 15 APR] There's so much good advice here I can't mark any one answer as correct. I upvoted all of the good answers and gave out likes.

I've been doing a lot of testing with landers this past week, and would like to share a landing technique that I've figured out in the process. Not sure if it's already commonly used or has a different name. If so, please let me know. The two most common landing techniques are the "suicide burn" and "zero descent rate" approaches. The suicide burn is a reverse vertical ascent-then-circularization burn. On the plus side, it can drop you in the neighborhood of where you want to be, but relies on perfect timing, high thrust to weight, and is hugely wasteful of fuel. The zero descent rate approach is the most efficient approach and doesn't require a high thrust to weight. It's the reverse of an immediate prograde burn to orbit. But on the downside, it's highly inaccurate AFA final touchdown point, and may smack you into terrain if you're not careful. I call this the "reverse gravity turn approach" and it has advantages over both of these techniques. It has medium efficiency, works with low t/w ratios, is very easy to execute, and will drop you right where you want to be with no fuss. I will demonstrate what you need to use this technique, starting with the vehicle: We are going for Tylo in this example, and this is our lander. DV is twice the "perfect" DV for Tylo according to WAC's DV chart In the case of Tylo, it says 2270 m/sec, so we'll double that to 4,540. T/w should be at least 1.2 at the body you wish to land on. No harm in going a little higher to start with, but keeping a low t/w will make your touchdown less twitchy because you have finer throttle control.

Hello there. I've been designing a LKO tourist vehicle, and my latest version has begun to hit some strange snags. Despite the COL being below the COM at all times, this rocket tends to flip over whenever I begin my gravity turn. Even the slightest nudge east causes it to spin. Any suggestions?

I'm having some serious issues with rockets flipping right when I start my gravity turn. I didn't have this problem pre 1.0. I just recently upgraded to 1.0.5 and the issue started. At first I thought it was due to the fairings bug, but this last rocket has no fairings. Mechjeb has the same problems, only earlier in the flight. The only mods I have are KER/MJ. I also cannot figure out how to attach an image right now but this seems to happen with almost anything I design. Please help because this has become extremely frustrating. Thanks in advance. http://imgur.com/sXfZXTX

Yes, there are a bunch of oldtimers who are going to moan and say "not this issue again!!?" Tough. Each new group of newbies needs to be exposed to the argument. If you don't want to see it, don't read any further. But I hope several of you will try to show me the error of my ways. @foamyesque & @Spricigo? So, I'm in the direct ascent camp. The gravity turn zealots make wild assumptions about how wonderfully efficient it is to do it their way. I say the gains are minimal at best, and it depends on whether you are calculating "efficiency" on the price of a kg to Munar or Minmus orbit, rather than deltaV. So let's try a competition. It only works if we all launch the same upper stage. So here's the one we are going to all use: http://www.virtualrealitytoursllc.com/pix/scan_sat.craft Here's a pic. Note the price = 16720 kredits. The rules are: you can add anything to the upper stage that you want to make it fly your way. You can try as many times as you like to be as efficient as you can. You can use MechJeb to fly it for you. Put the upper stage in (approximately) a 10 x 11.5 km orbit around your destination celestial body and report your total launch cost, the time it took to reach the destination, your remaining fuel, and the price per kg to reach that orbit. However, you may not remove anything from the common upper stage. Only additions allowed. Now, this is supposed to be a test of gravity turns. So SSTO spaceplanes are really not in the competition. But if any of you want to launch the upper stage as cargo in an SSTO and report the numbers, that would still be interesting. And I made it easy for you. I launched mine by eye. I didn't use any tools or maneuver nodes or anything. You can beat me by a bunch if I do that, right??! I even gave you a break on the time. I started a new game at Day 1, 0:00 and waited several hours for a launch window. Here's my launchable version of the rocket (note: grand total price = 30690 kredits): So my total cost to launch the upper stage was 30690 - 16720 = 13970 kredits. Proof that I got there -- and my mass in orbit = 7610 kg. Total flight time = 8 hours, 7 mins. With 675 fuel remaining. Cost per kg in LMO was 13970 / 7610 = 1.84 kredits per kg. And then I also did Minmus for fun. The numbers are almost identical. 1.85 kredits per kg. Total flight time (including waiting for window) = 6 days, 4 hr, 36 mins.

So basically whenever i launch a rocket, E.G a rocket to haul a space station up into orbit, it tips over. After the roll, i initiate the pitch, but then quickly loose control and my space ship literally tips over facing the ground. I tried MechJeb, Manual flight, but nothing works. Any help would be much appreciated.

Hey, How should optimal gravity turn look like? I mean when to start pitch and how much? I have my vessel at the edge of launch pad capabilities (mass 140 tons) and I count every m/s so I want to avoid pointless "pumping-up" my apogee (going to steep) or fighting through the atmosphere (going to flat). I saw some profiles on the internet but those are lacking precise values.My second stage burn is around 5 minutes.

What's a way to land onto a planet with minimal delta v? I'm aware of 2 ways, possibly 3. Pointing retrograde and firing engines until you land. Bad Doing a Hohmann transfer and then a landing burn. Better I've also heard ofa reverse gravity turn because NASA did it? Best??? Can anyone confirm the best way to land based on my three options? Suicide burn, constant altitude landing, and reverse gravity turn. I'm not sure if the third one works in ksp.

For my gravity turns, I watch my apoapsis(KER FTW!) and point my nose down the navball accordingly. At 5,000m, I turn to 70 degrees, then 10,000, to 60. Then about 15,000 to 45, 20,000 to 40. 25,000 to 35, 30,000 to 30, 35,000 to 25, 40,000 to 20, etc. Then by 60,000 I'm level and the distance of my aposapsis causes my thrust vector to push it slowly upwards still. What do you think? Too shallow, maybe? How do you do it? How should I modify mine?

Hello guys, I've been trying for over 2 hours to understand why my rocket goes insane when I am trying to perform a gravity turn and it never seemed to fix. I read through tons of forums saying that you should put aerodynamic fins but none of that worked. I tried with tons of different rockets and it didn't work. I even downloaded a Mun Rocket and the gravity turn still isn't working. I even tried using MechJeb and still not working. Can anyone help me?

Can't figure out the best way to get to orbit with this ship. Tried the new '10 degrees at 1000 m and STS off, 45 degrees by 15000 m etc... but the ship ends up at 45 degrees by 5000 m if I'm lucky. Please help! https://drive.google.com/file/d/0B3ppHHQCtIL5VHpObnl3cXhXXzQ/view?usp=sharing

I'm not sure if such a thing exists, or if it is wildly different for different craft with different TWR/ISP/etc. but I'm wondering if there is some sort of rule of thumb that I can follow. For instance, I know that I get more bang for my dV pushing my peri at my apo and pushing my apo at my peri. During liftoff, can I use my 'time to apoapsis' as a guide? Just wondering if there is something that I can do to be more efficient about my gravity turns without breaking out the graph paper and setting a bunch of explicit targets.

Hello! I would like to ask a quite complex question here. I am always using the FAR. So, it finally made me come across the idea that actually performing a real gravity assisted ascent the very same way it is done for more then fifty years in the real world would be the best way of getting my kerbals into orbit. How to calculate what should my rocket look like, how should it be balanced, what performance should it have to take me where I need it to be after the ascent? Is it possible to get into a circular orbit just with a gravity turn without the circularization? I guess many real rockets do the job this way... How should I fly the thing after it leaves the dense atmosphere and does not go prgrade automatically any more? Why are my thrust to weight ratios and g forces much lower than I would expect in real world on a realistic looking launch? Is it all about the size of the planet? Why do my rockets always tend to have their center of lift before their center of gravity even if they generally look like working rockets? To get around this without adding unrealistically looking fins that also add way too much stability and wobbling I would have to add payloads that the rockets would not lift of the ground at all. What do they do with this in the real world? Where do real thin and tall rockets like Redstone or Titan have their center of gravity on the launch pad? I guess not very high even regarding that kerbal parts are heavier than real ones. Can I automate the flying operations somehow in a manner similar to the real rockets? So, out of all this post the most important general question is how to predict and calculate a naturally going gravity turn and make it end up where I need it too. Thank you for all your help!

I have been putting the few Brain cells I have to work regarding gravity turns, and came to the conclusion that while in the atmosphere and wanting to maintain zero lift you can increase the Trun shape % by reducing TWR and you can decrease the turn shape percentage by increasing the TWR, but I am thinking that if you are limited to a TWR, and you accidently increase your Trun shape % too much, then when you try to increase it from that point with the max TWR you currently have, then you will not be able to stop the vector passing below horizontal before you want it to without correcting by pitching/yawing above the Velocity vector and thus presenting a huge side portion of you rocket to aerodynamic forces that may cause IRL un wanted damage. OOPS is there a mod or way to tell when you are getting close to you TWR's capability to keep your velocity vector above horizontal without needing to correct with the unwanted introduction of slip side drag destruction. Bryce Ring.

Refined Kerbin delta-v Launch 1500 m/s Up, 3000 m/s Gravity Turn Cross posted to r/KerbalSpaceProgram. If you like to budget your designs on delta-v there are two outstanding questions about the delta-v you need to launch from Kerbin: how much deltaV for primary ascent and how much for a gravity turn. [RESIZE=720] For the TLDR folks, the answer is in the title: a stage delta-v of 1500 m/s gets you moving straight up at terminal velocity and your fuel runs out around 12 km. The accepted answer for a Kerbin launch requires 4500 m/s so the gravity turn will require 3000 m/s = 4500 m/s - 1500 m/s. So if you're still around you'll probably be interested in specifics about the methodology. Obviously, this is pretty easy. Design a single stage ship with just enough fuel to get it past the 12km lower atmospheres bar. [RESIZE=720][/RESIZE] Recipe: 6x OX-STAT solar panels (top and bottom) above a Stayputnik pod. Below that we add 3x Z-200 battery rings. Below that a TR-18A decoupler. Below that a FL-T100 fuel tank with Lv-909 engine. The atmosphere Isp for the LV-909 is 300 s. Then add another 6x Z-100 batteries. The total mass is 1.28 and the dry mass is 0.78. The stage delta-v is 1450 m/s. I happened to conduct this research before I saw Scott Manley's adjustment video for gravity turn tutorials and learned that my target of waiting for barometric pressure to drop to 10% at 11.7 km for starting a gravity turn is too late. I did more testing and discovered that 1200 m/s gets you up to 8 km and it is possible to complete a lazy (did not move prograde fast enough) gravity turn into a circular 75 km orbit with only 3100 m/s in the second stage. 3000 m/s is enough to put you mostly in orbit and yet keep your second stage from turning into space junk.