Airplanes have been one of the most amazing inventions to date. The aviation sector has seen various milestones being set up year after year. This century has witnessed the evolution of the communication sector, with airplanes being the most advanced medium.
As a regular person, you must have wondered what makes airplanes so unique, let alone their skill of flying? It is speed. Planes are known for their super speed, which helps you fly across landmasses, within a matter of hours.
So, how fast does an airplane exactly fly? This question has intrigued numerous people. But even if it is the fastest mode of travel over oceans, it has numerical to which the measure is limited.
While in the air, an object tends to have two types of speeds; ground speed and airspeed.
Defined by its literal meaning, ground speed is self-explanatory. The time that the airplane takes to cover a certain amount of distance over the ground is known as ground speed. During the cruise altitude, an aircraft might have a ground speed between 300-600 nautical miles per hour.
Mostly the aircraft’s cruise at the same ground speed. However, wind plays a more significant hand in driving the plane while up above in the sky! A tailwind tends to push the airplane while a headwind slows the big machine down.
Airspeed has various variations to it. When an aircraft is still on the runway and has a headwind of 20 miles per hour, then the plane is said to have airspeed of 20 mph irrespective of the fact that it is moving.
This is because the airspeed is defined as the speed of the air over the wing. This speed over the wing helps to know how much lift it is producing. It is this lift that allows the airplane to support its massive weight and helps it to keep hovering high up.
But remember, whenever you ask a pilot about the speed of the machine he is flying, he answers it in the form of airspeed as it is this speed which keeps the airplane flying.
Mach Speed: Speed of Sound
When the aircraft attains a certain altitude (25,000-30,000 ft), the speed of sound is measured. This speed is termed as Mach Speed. It is defined as the percentage of the speed of sound. For example, a Mach number of 0.70 implies 70% of the speed of sound.
This speed differs as it depends upon the temperature of the air. The Mach number is taken as a reference as to when an aircraft approaches the speed of sound; shockwaves start to form, and hence the machine can face severe aerodynamic issues. Therefore, airplanes have a maximum Mach number of flying.
This is how the speed of a commercial airplane is measured. So, next time when a co-passenger asks you about the speed of the plane you are travelling in, you know how and what to answer!