تحويل سرعة الصوت إلى العقدة: تطبيقات الطيران والبحرية والعسكرية

At sea level in standard conditions (15°C, 1013.25 millibars), the speed of sound equals 661.5 knots exactly. However, temperature is the primary variable affecting sound speed—it decreases with altitude as temperature drops. At cruise altitude (35,000 feet where temperature is -56.5°C), the speed of sound reduces to approximately 660 knots. Military and civilian aircraft use these values for Mach number conversions, with pilots adjusting calculations based on actual temperature at their flight level.

Pilots use both because they serve different purposes. Knots measure actual airspeed relative to the air mass and determine ground distance traveled—essential for navigation, fuel planning, and air traffic control separation. Mach number measures speed relative to the speed of sound and indicates aerodynamic stress on the aircraft—critical for preventing structural damage, controlling shock waves, and managing compressibility effects. At high altitudes, an aircraft flying at constant knots will have different Mach numbers depending on temperature, so both measurements together provide complete flight performance information.