FS Design Studio (FSDS, short for Flight Simulator Design Studio) is a computer design program intended solely for the design, creation, and animation of aircraft and scenery objects for Microsoft Flight Simulator. It is published by Abacus.
History
Version 1 of FSDS came in two flavours, standard and advanced. The standard edition allowed for the creation of scenery objects only, while the advanced version also allowed for the creation of aircraft. The scenery objects could be compiled as separate scenery files (files which use the .bgl extension in Flight Simulator) or to be compatible with Abacus's scenery design program ASD or for use in the freeware Airport For Windows.
Version 2 streamlined the various versions down to one, which was capable of creating both scenery and aircraft objects. The most popular release at this stage was version 2.24, which was the last version made available for about three years.
Version 3 added support for aircraft created for Flight Simulator 2004, which entailed compiling the project using a tool provided by Microsoft named MakeMdl. The use of MakeMdl was a significant change for many FSDS users who had to get used to the new method instead of the previous way of just clicking a button and the program doing the compilation. Version 3 also removed support for scenery objects for ASD and Airport For Windows. Scenery objects were compiled as a model along with an XML file. Users would edit the contents of the XML file to contain the desired co-ordinates of latitude and longitude, heading, range and other characteristics. Version 3 also included for the first time a very crude implementation of boolean expressions.
When Flight Simulator X was released, Abacus's web site promised an update that would be made available within a few months, at a reduced price for those who already owned a valid copy of the software. They later revised this statement saying that the update would be available at no charge, but it took the better part of a year before FSDS 3.5 came out. Version 3.51 came out shortly after to correct some issues with the program.