Playback srenario avaliable here (zip format) or here (7zip SFX)
The controllable Shuttle-A (SH-02) is parked on a similar orbit, 7 km away if you want to do the tutorial yourself

Ok. Got the .scn? So *let's get it on!*

• Point the shuttle prograde - either by steering manually or by using the prograde autopilot.
• Observe Orbit MFD and fire the main thrusters until the number labelled "Ecc" reaches around 0.5 - then kill the engines with [*]. For a better precision keep decreasing thrust gradually by holding [Ctrl] all the time and pressing [Num -]

Right - time for some more theory.

The graphic for your orbit should now be quite elongated - you can modify the display of OrbitMFD to make it easier to read by using [right shift M] or MOD button repeatedly.

And there are two numbers listed on OrbitMFD directly related to these two points.

• PeR : Periapsis Radius - the distance of the periapsis from the center of the central body in metres.
• ApR : Apoapsis Radius - I bet you can't guess what this is...

Trap for beginners : PeR and ApR are measured from the center of the body, not from it's surface. If you don't pay attention, you may create a new crater on the moon... I recommend changing the distance display mode to Altitude [RShift D] or DST button what will change above values to PeA and ApA - altitudes from surface. The only thing you'll have to know now are atmosphere heights for planets and some moons but we don't care now since we are over Moon.

Two other number of interest are :

• PeT : The time in seconds until you next reach the periapsis.
• ApT : The number of seconds until apoapsis.

Almost every manouver related to changing the shape of your orbit is performed at one of these two points. OK, let's get out of the classroom for a bit.

• Coast around to the apoapsis - your current location is marked by the solid radial line of OrbitMFD. You may wish to accelerate time for a bit - use [T] to increase the rate, and [R] to decrease it. Don't exceed 1000x.
• Once about 40s to apoapsis, turn prograde and fire the main engines until the number labelled "Ecc" reaches zero (or as close as it will go) - watch the shape of your orbit as you do so. Decrease thrust as before ([Ctrl] and [Num -] and kill with [*]).
• We'll complete a quarter of orbit to enjoy the view... we're going back to the classroom soon.

A summary of what we have done so far : A prograde burn at periapsis increases ApA, and a prograde burn at apoapsis increases PeA. So to climb from a low circular orbit to a higher one, we need to make two burns - one to increase ApA to the required value, and one to bring PeA up to the same value.

Three more numbers of interest on OrbitMFD:

• Ecc : Eccentricity - descibes the shape of the orbit. A value of 0 indicates a perfectly circular orbit. A value from 0 to 1 indicates an elliptical orbit...higher values are more elliptical. A value greater than 1 means you are no longer in orbit - you aren't coming back.
• T : Period - the time in seconds to complete one orbit.
• Vel : Orbital Velocity in metres per second.

Take a note of your current velocity and period - they should be around 970m/s and 34,000s (that's about 9.5 hours).

Right - how do we get back down again? It should come as no surprise that we will be doing retrograde burns.

• Coast around to your apoapsis - actually, we don't really need to wait if our orbit is very nearly circular...every point on our orbit is roughly the same distance from the Moon anyway.)
• Turn retrograde, and fire the main engines until PeA is 40 km. If you overdo and make Pe negative, either jump to 2d cockpit [F8] turn on both AUX PODs' levers or switch RCS to translation mode [Num /] and use short burst with [Num 9] key (retro) and [Num 6] (pro). Another [Num /] returns to rotation mode.

• Coast around to the (new) periapsis (start turning retrograde 45s before), and perform another retrograde burn so that your eccentricity falls to around zero - be careful. Use all precise methods described before.
• Do a few orbits and enjoy the sense of speed...

Take a look at your new velocity and period - 1656m/s and 6700s (around 1.9 hours).
Even though to lower our orbit we used retrograde burns (which means we slowed down...), we are now going much faster...this result is very counter intuitive, but will be quite important later on.