Topic summary
Suborbital spaceplane
Extracted from the Wikipedia article Spaceplane.
Atmospheric reentry
Orbital spacecraft reentering the Earth's atmosphere must shed significant velocity, resulting in extreme heating. For example, the Space Shuttle thermal protection system (TPS) protects the orbiter's interior structure from surface temperatures that reach as high as 1,650 °C (3,000 °F), well above the melting point of steel. Suborbital spaceplanes fly lower energy trajectories that do not put as much stress on the spacecraft thermal protection system.