Estimate FS2004 disk space with add-ons, from a basic install to large scenery collections, and see how much free space installation needs.
Microsoft’s original FS2004 specification calls for about 1.8 GB of free disk space, but add-ons set the practical total. Budget 10–30 GB for a typical expanded installation, or 50 GB and beyond for large scenery and aircraft collections, while retaining extra room for downloaded archives, extraction and Windows temporary files.
How much space should I reserve for FS2004?
A 20–30 GB allocation is comfortable for FS2004 with a moderate selection of aircraft, airports, AI traffic and utilities. There is no maximum installation size: extensive regional scenery, photoreal ground textures and aircraft mega-packs can push the total past 100 GB.
| Type of installation | Typical contents | Practical space budget |
|---|---|---|
| Base simulator | FS2004 with little or no added content | 3–5 GB |
| Lightly modified | Several aircraft and a few airports | 5–10 GB |
| Typical add-on collection | Aircraft, scenery, AI traffic and utilities | 10–30 GB |
| Large collection | Many complete aircraft, regional scenery and texture packages | 50–100 GB or more |
These are planning figures rather than fixed installation sizes. Our FS2004 aircraft, scenery and utility library shows why totals vary so widely between users.
Which FS2004 add-ons use the most disk space?
Large scenery packages and complete aircraft collections usually consume the most storage, especially when they contain high-resolution textures, custom sound sets or many variants.
- Aircraft: A simple model may be small, while a package containing multiple liveries, panels and sounds can occupy hundreds of megabytes. Some of the largest FS2004 civil aircraft packages approach or exceed 1 GB as compressed downloads.
- Scenery: Small airport corrections may use only a few megabytes, but detailed airports and regional projects can require hundreds of megabytes or several gigabytes. The FS2004 scenery catalogue with package sizes provides useful examples.
- AI traffic: Flight-plan files are small, but complete AI fleets include aircraft models, textures and sounds. Installing many airlines can add several gigabytes.
- Mesh and ground textures: Wide-area terrain and photographic scenery can outweigh every other add-on category.
- Utilities: Weather programs, flight planners and ATC tools may install outside the FS2004 folder, so they will not appear in that folder’s reported size.
How do I measure my complete FS2004 installation?
The size of the Flight Simulator 9 folder is only the starting point because active scenery and supporting programs can be stored elsewhere.
- Measure the simulator folder. In File Explorer, open the properties of the main
Flight Simulator 9folder and record its size on disk. This includes content under folders such asAircraft,Addon Scenery,Gauges,EffectsandSound. - Check external scenery. Review the paths shown in FS2004’s Scenery Library. Add any scenery folders located outside the simulator directory.
- Include external utilities. Measure weather engines, flight planners and other programs installed separately from FS2004.
- Count retained downloads and backups. ZIP files, installers, repaint archives and copies of original files can equal or exceed the active installation.
A useful calculation is FS2004 folder + external scenery + separate utilities + retained archives and backups. This gives the real storage cost of the simulator rather than just its core directory.
Why does an add-on need more free space than its download size?
A package’s download size normally represents a compressed archive, not its final installed footprint. During installation, the archive, extracted files and installed copy may all exist at once.
Keep at least two to three times the download size free while installing a large package, and allow more for highly compressed scenery. Legacy installers may unpack files into the Windows temporary folder on the system drive, so an installer can report insufficient space even when the FS2004 drive has plenty available.
Once an add-on works, unwanted extracted folders can be removed and the original archive can be moved to another drive. Do not delete shared gauges, effects or scenery files merely because their source package has been archived.
Can FS2004 scenery be stored on another drive?
Yes. FS2004 can use scenery stored on another drive when that folder is registered through the Scenery Library, making scenery the easiest large category to separate from the main installation.
Aircraft and shared simulator files are best kept in their expected FS2004 folders because older installers often rely on the registered FS9 path. Moving the complete simulator directory manually can also confuse those installers. For correct folder placement, use our FS2004 add-on installation procedure rather than copying every package into the same directory.