Best way to get into orbit?

[astroboy820]

When I takeoff, I normally point my ship directly up, but the prograde moves all around. Is it better to point directly up or follow the prograde symbol?

Edited August 29, 2013 by astroboy820

[MistaX8]

Go straight up until you hit 10,000 meters. Then between 10,000 and 15,000 make your turn from straight up to about 45 degrees in whatever direction you plan on making your orbit. From there you can leave it until your Apoapsis is high enough for orbit (anything above 70km) but as you get better at the game you can start doing smoother turns. Once you get the apoapsis where you want it kill your throttle and wait until you are closer to it. Using a maneuver node can help you figure out exactly when to start burning. When you get close to it burn prograde until your periapsis gets at least above 70km. You are now in orbit.

It's probably a good idea to keep your speed under 200m/s for the first 10km as going any faster through the thickest part of the atmosphere just wastes fuel.

Scott Manley's tutorial (recorded with an older version but getting into orbit is still the same, if you've already got a decent rocket build, the launch starts somewhere after the 15 minute mark in the video).

[Spyritdragon]

I tend to entirely disregard whatever speed im going at, but look at my G-metre. I used to stay under 200 m/s up untill 10.000 metres up, then throttle up to full and make a turn to 45 degrees. Recently i've been able to get into orbit much more fuel-efficiently by just looking at my G-force meter: I reduce/increase engine power to try to keep it at 1.5 G's. I try not to let it over 2 G's, most importantly.

I usually go up to about 12.000 metres, make a turn to about 45 degrees, then at about 24.000 metres go down to 60 degrees, and pitch horizontally more and more as my apoapsis rises. When my apoapsis gets to 70 i usually start to go entirely horizontal untill my periapsis goes over 70 too or my apoapsis hits 100. Whenever i go to orbit i usually go for a 100 km parking orbit, from where i adjust to whatever orbit i want it in. I have very little crafts that have orbits under 100 km in radius - i like my safety margin and a margin to make my orbit lower than it so i can catch up to it.

[Kerbal01]

Turn to the east(using the d key) at 10,000 m. bank over to 45 degrees. at 1100 m/s when your apoapsis is at or above 70 km bank all the way over to zero degrees shut down your engines with x coast to 30 sec before apo re ignite engines and circularize so that periapsis is above 69.5 km.

[lajoswinkler]

Typically I lift at 150 m/s until 7-8 km, straight up. Then I tilt 10-20° and let the speed (at the same throttle) reach 200 m/s. The acceleration tells me the atmosphere is suddenly starting to get really thin. Time for action. Around 20 km, I slowly start turning to 45° tilt. At 50 km I start tilting it towards the tangent (0°).

If I'm at 50 km height and my apoapsis is above 75km, I significantly lower the throttle until I'm relatively close to apoapsis, or even turn it off. When I'm close, I throttle up, managing the tilt in the -10° to +10° region, to make sure I'm very close to apoapsis all the time. That's the efficient way.

Be sure that, close to exiting the atmosphere, you're at couple of hundreds of m/s. Otherwise you need to burn away from the tangent to push the periapsis out of the Kerbin, and that's terribly wasteful. Scratch the design and start again.

People often make the mistake when they use full throttle all the time, thinking they need to hurry up because time is running out. There's no need for that. What's important after leaving the atmosphere is staying close to the apoapsis. Lateral movement is momentum conserved, there's no drag. Be patient and balance around the apoapsis until your periapsis climbs above 70 km.

When extending your apoapsis, do it from the periapsis. It's the most efficient way because that's the point with the highest kinetic energy. Bottom of the hill you're rolling towards.

When reducing the periapsis, do it from the apoapsis. You get the gist. Yellow prograde/retrograde markers.

When changing inclination, do it at the orbital nodes (ascending/descending node) using the magenta normal/antinormal markers. If you see your orbit going out of control, correct it with yellow markers. Little bit of magenta, little bit of yellow, until you reach the desired inclination.

I rarely use blue radial-in/radial-out markers, but they can be very useful, to me mostly on orbit insertion, to correct the maneuver and to decrease the amount of fuel. It's when you're approaching at a weird angle, or the time before escape is short.

Read this thoroughly.

Edited August 24, 2013 by lajoswinkler

[capi3101]

Everybody goes into orbit slightly differently...it's really somewhat dependent upon the design of the craft and how you're comfortable flying it. I used to fly like MistaX8 said - straight up to 10,000 then 45 degrees at 090 until my apoapsis hit 100k, then shut down and plan a burn at apoapsis to raise the periapsis out of atmo. Nowadays, I fly more like Spyritdragon.

Here's how I like to go:

1) Try to follow the terminal velocity curve as closely as I can manage through the first 10,000m, flying straight up (idea is to get out of the troposphere as quickly as possible). That's 130 at 3000m, 160 at 5000m, 210 at 8000m and 260 at 10,000m.

2) At 10,000 or shortly thereafter, come to course 090, 45 degrees elevation. Speed matters less than gee-force at that point; watch the gee meter for the rest of the ascent. Keep it below 2 gees or you might get a telescopic RUVD.

3) Watch the time to apoapsis. At 30,000 meters, if it's less than 30 seconds, stay at 45 degrees elevation until the time goes to 35s. If somehow it's above 45 seconds, go horizontal for a bit until it's less than 40s. Otherwise, tilt down to the prograde vector; this should usually be somewhere around 10-20 degrees elevation.

4) At some point, you're going to start gaining a lot of time to apoapsis; this is normal - let it happen but don't change your course.

5) At 50,000 tilt to 5-10 degrees elevation. Watch the gee meter and the apopasis elevation. Kill your burn if the apoapsis gets much above 100k.

6) If done properly, your apoapsis will stay above the atmosphere as you coast up. You may even have a periapsis above Kerbin's surface; if so, great. Wait to apoapsis and burn to circularize.

By doing the ascent this way, you shouldn't have to spend much delta-V or time to circularize. I think the shortest burn I've had so far was four seconds or so.

I've heard folks say that you should watch Mechjeb handle an ascent and try to emulate it when you're flying manually. I've seen folks launch with Mechjeb on YouTube and I'll even recommend you watch how it does it a time or two; you can learn a lot from it (for the record, I fly manually).

[Curiosity7907]

Ok so what you call 45 degrees at 10km I call 50 degrees at 10km and 40 degrees at 20km 30 degrees at 30km and so on.

I don't like directly tipping over to 45 degrees at 10km a like to slowly turn to 45 degrees because I don't do complete kerbal gravity turn I also try to do realistic gravity turn.

I try doing realistic things like I make my first stage long and powerful like Nasa and second stage short low thrust but high specific impulse.

[Harry Rhodan]

1 hour ago, Curiosity7907 said:

Ok so what you call 45 degrees at 10km I call 50 degrees at 10km and 40 degrees at 20km 30 degrees at 30km and so on.

Could you please stop necroing old threads on a daily basis? Most of the problems and information in those threads are completely obsolete and the people who asked these questions have long been gone.

[sal_vager]

@Curiosity7907, please check the date of the last post in future, this thread is old and the information it provides is no longer relevant.

Closed thread.