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Differences between Subsonic, Transonic, Supersonic, and Hypersonic Flight

In aeronautical engineering, the differences between subsonic, transonic, supersonic, and hypersonic flight are based on the speeds at which an aircraft travels relative to the speed of sound.

• Subsonic: Subsonic flight occurs when an aircraft is flying below the speed of sound, typically at speeds up to Mach 0.8. Most commercial aircraft operate in subsonic speeds.
• Transonic: Transonic flight occurs around the speed of sound (Mach 0.8 to Mach 1.2). This speed range can result in a mix of subsonic and supersonic airflow around the aircraft.
• Supersonic: Supersonic flight is when an aircraft travels faster than the speed of sound (Mach 1). It creates shock waves and sonic booms. Examples include fighter jets and the Concorde.
• Hypersonic: Hypersonic flight is at speeds greater than Mach 5. At these speeds, the air around the aircraft is highly ionized, and the heat generated can be a significant challenge to overcome in design.

Each type of flight has its own set of challenges and considerations in terms of aerodynamics, propulsion, and structural design.

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