Frequently Asked Questions.
Orbiter is a real-time 3D space flight simulator for the Windows PC. The concept is similar to traditional flight simulator software, but you are not limited to atmospheric flight. Orbiter allows you to experience manned and unmanned space flight missions from the pilot's perspective. Take control from launch to orbtial insertion, rendezvous with space stations, deploy and recapture satellites, and re-enter and land on a planetary surface. The playground is our solar system, and you can even execute missions to the moon or other planets. (Time compression is available to shorten long cruise phases.) Orbiter accurately models the physics of spaceflight, which makes it possible to either recreate historic missions, or use it as a sandbox for futuristic spacecraft concepts.
The full Orbiter software can be downloaded from this site and is free for personal and non-commercial use. For details, see the Orbiter Freeware License terms. You can distribute Orbiter, but you are not allowed to charge a fee for it. If you paid for Orbiter (either on its own or as part of a compilation), you have probably been ripped off.
If you like Orbiter, you can show your appreciation by making a donation, but this is entirely voluntary.
If you want to use Orbiter in a context not covered by the freeware license terms, you must get written permission from the author.
Note that 3rd party Orbiter addons may be distributed under different licensing terms.
There is a web-based Orbiter
message board where you can post general questions and suggestions. It has dedicated sections for bug reports, addon topics, and all things spaceflight.
I don't announce release dates and feature lists. This is mainly because Orbiter is a hobby of mine, and I don't need the pressure of working against a deadline or fixed specification. I can't always predict how much time I can spend on Orbiter, so the interval between releases will vary. The features added in a new version are usually a mixture of my own ideas and user requests.
Remember you need only the "Base" and "Textures" packages to run Orbiter. Everything else is optional. Select a download mirror close to your location, and if necessary, try several (try to avoid the medphys server, because excessive demand on that server will get me into trouble ;)
If you want to create your own addons, you should download the Orbiter SDK (software development kit) package. This contains the libraries for compiling your own spacecraft code, sample code, a few utilities and documentation.