Hi JackBush, I'm a pretty new player too. "Ideal" would be zero I guess?? I saw a video where someone's burn time was 4 seconds. But you don't need to aim for that now. You're just trying to get into orbit and you can do it inefficiently. My burn times are usually between 30 seconds and 2 minutes depending on what sort of monstrously heavy ridiculous thing I've built. Your rocket looks like a it is carrying a lot of dead weight. Although creating massive rockets is the Kerbal Way, one lesson I learned recently is that sometimes less is more. Sometimes if a rocket doesn't seem to get to orbit, it's because it has too much fuel, not too little. The rocket I usually take up to orbit (with plenty of fuel to spare these days) looks like your long center one, with only two solid boosters (the mid-size ones). Here's a picture: Yeah it's not the world's fanciest or best designed. I can see a lot of things I'd do differently. But it gets me there. My fuel tanks are 4 FL-T400s, 3 on the initial stage and the 4th up above. The solid boosters and the "swivel" engine fire on the same stage. My upper stage engine is a "terrier". Basically what I do is enable SAS, throttle to max with Z, then fly up, tilting over gradually with an aim to be at 45 degrees when I'm at about 10km. After that I do keep turning over gently, but not too much. Dump those solid rocket boosters as soon as they are empty (it will happen fast). When I'm around 30km I switch up to map view and look for my apoapsis. Mouse over it, and just keep staring at it until it is above 70km (I usually go for about 80km) and then cut the engines with X. Once I've cut the engines, then I set up the maneuver mode at apoapsis. You need to do this kind of quickly! Just click at apoapsis and pull your prograde marker (the green one without the X through it) until the apoapsis and the periapsis switch. You should then have a time to apoapsis and an estimated burn time. You'll also have that blue marker on the nav ball telling you which way to burn. Once you are above 70km, turn towards that blue marker, even if you have some time before your burn. Basically you want to do half your burn before apoapsis and half afterwards. If you have some time before then, zoom out and you'll notice that your orbit probably isn't perfectly circular. I always overshoot a bit! You can pull the retrograde marker a bit to bring yourself closer to a circle. Then burn when your time to apoapsis is half of your total burn time. I almost always run out of fuel on my launch stage during this burn, so if that stage is almost out of fuel, give yourself some more time because the terrier engine is less powerful but more efficient. I know this is not the best way to get into orbit but even noobs can do it! You don't have to be perfect. Good luck!!