Mach Number
Definition
The ratio of true airspeed to the local speed of sound. Mach 1.0 is the speed of sound, which varies with temperature and altitude. Transport aircraft typically cruise between Mach 0.78 and 0.85.
Why Mach Number Matters for Pilots
Understanding Mach Number is critical for passing the FAA Private Pilot Knowledge Test and performing safely in flight. Aerodynamics questions make up a significant portion of both written exams and oral checkrides. Pilots who grasp concepts like Mach Number can make better decisions during all phases of flight, from takeoff to landing.
Exam Tip
This concept is commonly tested in aerodynamics-related questions on FAA and EASA exams. Make sure you can explain Mach Number in your own words for the oral exam. Practice applying this concept to real-world scenarios, not just memorizing the definition.
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