Basic maneuvers
This is a brief "cheat-sheet" of orbital manuvers, low on details, math, background info or video content (these are all better provided by other pages and articles). This is instead meant as a quick reference while in-game.
Contents
Ascend to Orbit
- Ascend straight up for at least 10 km. See table below for optimal ascent speed.
- After 10km, begin your gravity turn by slowly leaning east (bearing 90 degrees on your navball, usually "right" from the standard launchpad). You can lean other directions as well but going east saves fuel by moving with Kebral's own spin.
- Continue to accelerate until your apoapsis (hit M and mouse over the Ap node) is greater then 80 km (the end of Kerbal's atmosphere) - idealy around 100km.
- Cut your engines and wait until you are getting close to the apoapsis point.
- Accelerate prograde (i.e. the direction you are going, represented by a green circle on your navball) until your periapsis (also visible on your map) is also around 100km.
You can save fuel by being close to your terminal velocity during ascent. Lower velocity wastes delta-V on gravity, higher is wasted on air resistance:
| Altitude (m) | Aprox. Terminal Velocity (m/s) |
|---|---|
| 500 | 105 |
| 1,000 | 110 |
| 2,000 | 120 |
| 3,000 | 130 |
| 5,000 | 160 |
| 8,000 | 215 |
| 10,000 | 260 (remember to start your gravity turn!) |
| 13,000 | 350 |
| 15,000 | 425 |
| 16,000 | 470 |
| 32,000 | 2250 |
Change Orbital Shape
Lower your apoapsis by burning retrograde (see navball) at your peripasis. Raise your apoapsis by burning prograde at your periapsis instead.
Lower your periapsis by burning prograde at your apoapsis. Raise your periapsis by burning prograde at your apoapsis.
Match Orbital Inclination
If you want to orbit on the same plane as another object (planet, ship, etc) - set it as your target in the map view. You will see two green arrows labeled as the "ascending node" or "descending node" where your orbits are closest. At either of those points burn either "normal" or "antinormal" (which simply means "north" or "south" respectively if you are starting from an equatorial orbit).
If you need several burns to get to your desired inclination, remember that if you burn "normal" on one node you need to burn "antinormal" on the other to keep going the same direction.
It might also help to plan your burns using the orbital maneuver planning system in the map view, where normal and antinormal directions are labeled with purple arrows.
