1. What is Mach Number?

The Mach number is a dimensionless quantity representing the ratio of flow velocity past a boundary to the local speed of sound. It's commonly used in aviation and aerodynamics to describe aircraft speeds.

2. How Does the Conversion Work?

The conversion formula from knots to Mach is:

Where:

• 1 knot = 1 nautical mile per hour
• 661.47 knots = speed of sound at standard sea level conditions (15°C, 1 atm)

Explanation: The Mach number is calculated by dividing the speed in knots by the speed of sound in knots at standard conditions.

3. Importance of Speed Conversion

Details: Converting between knots and Mach is essential for aviation applications, particularly for high-speed aircraft that operate at significant fractions of the speed of sound.

4. Using the Calculator

Tips: Enter speed in knots (nautical miles per hour). The value must be positive. The calculator will automatically compute the equivalent Mach number.

5. Frequently Asked Questions (FAQ)

Q1: Why is 661.47 knots used for the speed of sound?
A: This is the speed of sound at standard sea level conditions (15°C, 1 atmosphere pressure). The speed of sound varies with temperature and altitude.

Q2: How accurate is this conversion?
A: This conversion is accurate for standard sea level conditions. For other altitudes/temperatures, a more precise calculation would be needed.

Q3: What's the difference between Mach and knots?
A: Knots measure speed (nautical miles per hour) while Mach is a ratio comparing speed to the local speed of sound.

Q4: What Mach number is considered supersonic?
A: Mach 1 is the speed of sound. Speeds above Mach 1 are supersonic, while speeds below are subsonic.

Q5: Do commercial airliners fly at Mach speeds?
A: Yes, most commercial jets cruise at about Mach 0.78-0.85, while supersonic jets like the Concorde flew at Mach 2+.