The best Flight Simulator alternative to Universe Sandbox is Orbiter, which is both free and Open Source. If that doesn't suit you, our users have ranked more than 10 alternatives to Universe Sandbox and three of them are Flight Simulators so hopefully you can find a suitable replacement. Other interesting Flight Simulator alternatives to Universe Sandbox are Space Simulator and Reentry.
Orbiter is a realistic 3D real-time space flight simulator program.
Fed up with space games that insult your intelligence and violate every law of physics? Orbiter is a simulator that gives you an idea what space flight really feels like - today and in the not so distant future.
Space Simulator is a realistic space flight simulator for iOS and Android. It is an open-ended simulation where players can free roam Solar System or reenact historical NASA space program missions.
Reentry is a space flight simulator based on real life spacecrafts. You create a new astronaut, gain levels and experience for every move you make by completing missions in space.
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