USS Jeffries Orbiter tutorial

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Introduction

This tutorial has been written as a landing aid for a specific add-on, and therefore a lot of it will apply only to that add-on and specific situations, although most of the knowledge gained will be useful when applied to other Orbiter spacecraft.

Files needed for this tutorial

1. Orbiter - available from the download section at orbitersim.com (http://orbit.medphys.ucl.ac.uk/download.html). Just the base package is all you really NEED to download here, but the extra textures will make things like the earth look even nicer.

2. USS Jeffries add-on. This can be found at orbithangar.com (http://orbithangar.com/searchid.php?ID=1299)

3. A scenario file to start you in space. You can get this right here (http://www.4shared.com/file/8113384/317cd4f3/Tutorial_Scenarios.html)

Chapter 1: A few important things to remember about space

Flying in space isn't the same as flying in an atmosphere (rather obviously). The biggest difference is that all of your ships movement is controlled by its thrusters and engines, not by lift from the wings or rotors. As there is no air in space to provide friction, ANY THRUST YOU APPLY NEEDS TO BE CANCELLED OUT TO BECOME STATIONARY WITH A TARGET.

What this means is that you need to remember one important thing - leave enough time to burn your thrusters to slow your ship. Since cancelling out your movement takes just as long as it did to accelerate, it pays to move slowly and not apply too much power at once.

Remember that although you are always going to be moving when in orbit, the only thing we need to worry about at the moment is the RELATIVE speed between your vessel and the target.

A quick note about your vessels

Being a Sci-fi vessel, the author of the Jeffries add-on kindly decided to make the fuel supply last forever. Happily this means you don't need to worry about messing up too much, as you'll have both enough power and enough fuel to correct your situation and try again. While this might not apply too much to the landing tutorial, it'll become more useful when we get onto more advanced stuff.

The Jeffries is also very heavy, and the scout very light. This was done intentionally to attempt to reduce the effect of the "docked ship rotation bug", an unresolved bug in Orbiter whereby ships docked together rotate inexplicably while under high time compression. The only time we have to worry about this is when flying interplanetary missions, which we'll get to later. Until then just notice that if you fly the scout on a planet it seems very light and may behave oddly.

Chapter 2: Orbiter controls

Your vessel is controlled primarily by use of they keypad, with other useful functions (such as the HUD and MFD's) being controlled with the keyboard. We'll cover those commands when they're needed.

Primary controls

Your vessel is moved in space by its main engines and thrusters. It has three sets of engines, and one set of dual-mode thrusters.

Primary engines - these fire from the back of the ship, pushing it forward. They are controlled with the "+" key on the keypad. Tap it for a quick burst, press and hold for a longer burst (release to stop firing) and can be scrolled by holding "Ctrl" and pressing. Releasing the "+" key will stop scrolling the engines and they will stay locked on at that power. This is useful for either long burns in space or flying in an atmosphere. To lock in full power quickly, press and hold "+" and then hit "Ctrl". Releasing both keys will lead to full power locked on. To reduce power, hold "Ctrl" and "-". Locked thrust can be cancelled with " * ".

Retro engines operate in the same manner as the primaries, but by use of the " - " key.

Hover engines are mounted under the ship to provide lift on a planet. They are controlled by the "0" and " . " keys on the keypad. NOTE: the hover engines only scroll, and cannot be burst fired like the main and retro engines.

RCS Thrusters: the thrusters work in 2 modes, rotation and translation. Rotation mode firs the thrusters such that the ship rotates about its axis, and translation mode moves the ship laterally. THE MODE IS SWITCHED WITH THE " / " ON THE KEYPAD.

RCS Mode indicator

Rotation mode:

Translation mode:

Engine thrust indicators

Kill rotation ( "5" ): keypad "5" activates the killrot autopilot mode. This mode uses the thrusters to cancel out your vessels rotation. It is very useful AND BEST USED AFTER EVERY ROTATION. Note that it stays on for a period after rotation seems to have been killed. When activated the KILL ROT light is lit in the autopilot bar at the bottom of the screen.

Autopilot bar

Controlling views

To switch to an external view of your ship, press F1. F2 controls different view modes, "Z" and "X" control the field of view. Rotation of the camera can be accomplished with the right mouse button or "Ctrl" and the arrow keys. Note: holding the right mouse button in the cockpit view will allow the camera to be moved. This is so you can view virtual cockpits, but as neither of the ships used in the tutorial has one, it can be confusing. Moving the view back near the middle of the screen will snap the camera to face forward. If you can find the middle again, simply switch to an external view and back again, and this should reset your view.

Zooming can be achieved with either the mouse wheel or the "-" and "=" keys on the main keyboard

Basic Orbiter set-up

Installing Orbiter: just unzip the file - it will maintain folder coherency. To install any high res textures or add-ons, just unzip into the primary Orbiter folder. Almost all add-ons maintain folder coherency and therefore install to the correct place. The same applies to my scenario pack - just unzip straight into the main Orbiter folder.

Once you have unzipped all the necessary files, load orbiter.exe. You'll be presented with the front-end. This view shows a list of folders containing scenarios for you to try out. We'll come back to this in a moment. Click the parameters tab, and change the MFD refresh rate to 0.01. In the video tab change the settings to your personal preferences. I would recommend using full screen mode, as the on-screen text can be difficult to read in when windowed.

Chapter 3: Let's go for a flight

The aim of this test flight is to familiarise you with controlling a spacecraft. In the scenario tab select the folder Jeffries and the first scenario file, "Tutorial 1". Click "Launch ORBITER" to start the scenario.

This scenario will start you off in the scout's cockpit, located in the Jeffries hangar bay, ready to launch. Press "CTRL + D" to undock. Switch to external view and watch your scout rise majestically out of the bay. Right click and hold and look around your ride. Use the mouse wheel to zoom.

Now to demonstrate what we learnt about space. The RCS is in translation, or linear, mode. Change it to rotational mode by pressing " / "(notice the RCS indicator changes to "ROT"), then press and hold a key and watch as your ship starts to spin. Notice that as you hold the key down, the ship's rotation accelerates. Notice also that when you release the key, the ship continues to rotate. Press keypad "5" and watch as the autopilot stops the ship from spinning. This might take a long time if you put your scout into some kind of crazy multi-axis spin.

Take some time to play with the main and retro engines as well. You can use the rapidly shrinking Jeffries as a reference point. Notice that they're pretty powerful - using them to dock later will be interesting. Fire up the hover motors too, and watch as you accelerate away from the Jeffries. Turn them off when your ready - you might have to look at the indicators in the top left of the cockpit view to make sure the engines are all off.

You can play with the RCS in translation mode here too, but you probably won't see much difference in your flight, since they're quite weak. Just get accustomed to the controls, as you'll need these for landing and docking.

Chapter 4: docking

This chapter will walk you through docking the Scout to the Jeffries. Load the "Tutorial 2" scenario. This will place you in the scout, above and behind the Jeffries, ready to make your landing.

In order to dock in the Jeffries bay, we will have to use the docking MFD. This is displayed in the bottom left MFD window in the cockpit. While it looks confusing to start with, a short description will make it clearer.

The MFD is broken down into 4 parts: the rotation arrow, the rotation X, the locating + and the distance ring.

The rotation arrow shows the rotation of the target docking port relative to yours. It is aligned when it's at 12 o'clock and changes colour. Use the yaw keys (RCS rotation mode, keys 1 and 3) to align the arrow.

The rotation X shows the alignment of your ship in the other 2 axes (roll and pitch). Try to get this X central on the MFD. It will turn from red to grey when your alignment is correct.

The locating + shows the location of the target docking port relative to yours. Use the translation thrusters to get this cross central.

The distance circle shows how far you are from the target, and decreases in size the closer you get (vertically) to the port.

There is also a distance indicator and a relative velocity indicator.

The first thing to do is to move your ship forwards, so it is over the landing bay and the docking port. A short (and I mean short - less than a second) burst from the main engines will get you moving forward at a decent pace. As you move over the bay, and the lip disappears, fire your retros briefly and try to come to a halt relative to the Jeffries. You will probably need to use the translation thrusters to kill out all of your movement - this can be seen by the yellow arrow coming from the centre of the MFD. Use the thrusters to get this arrow as short and central as you can.

Use the rotational thrusters to make sure you orientated correctly and that the rotation arrow and alignment X are in the correct places. Don’t forget to use the killrot autopilot ( "5" ). Use the translation thrusters to place the location + in the middle of the MFD. You are now right above the docking port and perfectly aligned to land.

Use the translation thrusters to move downwards into the bay. Take it slowly, and correct your position when the + drifts away from the centre. Use small bursts watching the yellow arrow, and don’t forget to cancel your thrust to keep you in position. Watch as the distance readout gets smaller, and if you're still lined-up you should see the scout "snap" to the docking port. Welcome aboard Midshipman!

If you don't dock to the Jeffries then you weren't aligned properly - either out of rotation or not located properly. You probably flew right through the deck. That’s ok, just thrust upwards and try again. Docking can be challenging, but its rewarding when you get it right!