Install FlightGear on macOS with the correct Mac download, DMG setup, Apple silicon advice, Gatekeeper fixes and first-launch checks.
To install FlightGear on macOS, download the Mac disk image, open the .dmg, drag FlightGear into Applications, then launch it from Applications. If Gatekeeper blocks the first launch, use macOS’s approved Open command rather than disabling security features. Choose a package compatible with your Mac’s processor and macOS release.
FlightGear macOS installation steps
- Check your Mac: Open About This Mac and note the macOS version and whether the processor is Apple silicon or Intel. Before downloading, check FlightGear’s hardware, graphics and storage requirements. Allow extra storage for scenery, which can become much larger than the simulator itself.
- Download the Mac package: Get the disk image from our dedicated FlightGear macOS download page. Wait for the browser to finish downloading before opening the file.
- Mount the disk image: Double-click the downloaded
.dmg. A Finder window should appear after macOS verifies and mounts it. - Copy FlightGear to Applications: Drag the FlightGear application into the Applications folder shown in the disk image. Most Mac releases use this drag-and-drop method; if the image contains an installer package instead, open that package and follow its prompts.
- Eject the disk image: Eject the mounted FlightGear volume in Finder. Launch the copy in Applications, not the copy inside the disk image. Running permanently from the mounted image can cause failed updates and settings problems.
- Approve the first launch: If macOS blocks the application, Control-click FlightGear in Applications, choose Open, then confirm Open. This creates an exception for that application without switching off Gatekeeper for everything else.
- Test a default flight: In the FlightGear launcher, use a bundled aircraft and the default location before adding custom content. If that flight loads, the core installation is working.
If you cannot write to the system Applications folder, macOS may request an administrator password. A user-level Applications folder can also work where account permissions permit it.
Which FlightGear Mac download should I choose?
Choose a native package for your processor when one is offered; a universal package supports both processor families.
| Your Mac | Preferred package label | Compatibility caveat |
|---|---|---|
| Apple silicon | Apple silicon, ARM64 or universal | An Intel or x86-64 build may work through Rosetta if that FlightGear release supports it. macOS normally offers to install Rosetta when required. |
| Intel | Intel, x86-64 or universal | An Apple-silicon-only package will not run on an Intel Mac. |
Package choices vary between FlightGear releases. Also check the stated macOS requirement: the correct processor build can still fail if it requires a newer operating-system version than the one installed.
How do I open FlightGear if macOS blocks it?
A Gatekeeper warning does not always mean the installation failed; the remedy depends on the exact message.
- “Developer cannot be verified”: Control-click the installed application and choose Open. If necessary, attempt one launch, then look under Privacy & Security for an Open Anyway option. Apple changes the wording and location between macOS releases.
- “Application is damaged”: Delete that copy and download the disk image again. An incomplete download, altered application bundle or incompatible package can produce this message.
- Crossed-out icon or compatibility warning: Check the processor architecture and minimum macOS version. Reinstalling the same incompatible package will not fix it.
- Rosetta prompt on Apple silicon: An Intel build needs Apple’s translation component. Allow macOS to install it, or use a native Apple-silicon or universal FlightGear package if one is available.
We do not recommend disabling Gatekeeper globally or using Terminal commands that remove security checks. Only approve an application after confirming that it came from the intended download.
Why does FlightGear open but fail to start a flight?
If the launcher opens, FlightGear itself is installed; a failed flight usually points to scenery, graphics or incompatible custom content rather than the application copy.
- Test with the launcher’s default aircraft, location and rendering options.
- Remove custom command-line options and external aircraft paths temporarily.
- If terrain is absent only outside the bundled area, configure automatic scenery downloading or follow our FlightGear scenery installation instructions.
- If the window closes during loading, compare the Mac’s graphics support and memory with the simulator requirements, then retry without add-ons.
How should I update FlightGear on a Mac?
Quit FlightGear, mount the newer disk image and replace the application in Applications. Keeping the previous application under a different name gives you a simple rollback, although different releases may still share user preferences.
A mistake we see constantly is placing downloaded aircraft inside FlightGear.app. Replacing the application can erase those files, and modifying the bundle may also interfere with macOS verification. Keep custom aircraft in an external folder and use our aircraft add-on installation steps to connect that folder to FlightGear.