reentry vehicle

A reentry vehicle is a spacecraft designed to return to Earth's atmosphere. This process utilizes atmospheric drag for braking, but also generates intense heat due to air compression. Early reentry vehicles used ablative heat shields that burned away, while the space shuttle introduced refractory materials like silica tiles. Newer designs incorporate active cooling and metallic alloys.

Precise control of the reentry angle is critical. Too shallow an angle causes the vehicle to skip off the atmosphere, while too steep an angle can overwhelm the heat shield and deceleration forces. Vehicles like the Apollo Command Module approached Earth at high speeds, experiencing temperatures near 3,000°C (5,400°F). Some spacecraft deploy parachutes for a soft landing, while others, like the space shuttle, glide and land like airplanes. Carbon-carbon composites, which retain strength at high temperatures, are used in nose cones but require protection from oxidation.12