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In space, spacecraft are only affected by two of the four forces of flight, weight and thrust, so not all of the control surfaces in an airplane apply. In open space, simple forward and backward thrusters will speed you up or slow you down. When a spacecraft is orbiting Earth, it can change its orientation with small thrusters or a system of reaction wheels that rotate at right angles to each other. Check out the Moving in Space page to see the Space Shuttle Discovery performing a backflip!

Once the spacecraft reenters Earth's atmosphere, it has used all of its fuel, so it acts like a glider. The pilot maintains control with the same control surfaces as a delta-wing airplane.