The higher the flight, the more fuel-efficient the aircraft is, the faster and quieter it flies. But they can't fly into space because of some design limitations.
According to ScienceABC, commercial aircraft often fly stably at an altitude of 10,700m above the ground. This is considered the ideal height to help airlines save money, fly faster and safer.
There are three main reasons for this.
The higher the flight, the thinner the air density . This helps reduce the drag of the aircraft. Besides, the air pressed down into the fuselage is also lower than the lifting air.
At the same time, the aircraft must also move faster to gain additional lift of the air. So when traveling at high altitudes, the aircraft will consume less fuel and fly faster.
Because of some design limitations, civil aircraft cannot fly into space.
Another reason is comfort. An aircraft can fly at altitudes of 10,700 - 42,000 m from the ground. Weather phenomena are most influential at altitudes of 0-10,700 m.
If flying at this altitude, the aircraft will not be affected by such turbulence weather. This helps passengers experience a softer and more comfortable flight.
The last reason is for everyone's safety. In case the aircraft is at an altitude of 11,900 m and something happens to the engine, pilots will have more time to troubleshoot and contact the operating center before an emergency landing.
Most modern aircraft have very good incident response systems. People often think that when the engine is broken, the plane will free fall. But the truth is not so.The plane will hover forward .
Air turbulence due to terrain will not impact the aircraft if it reaches a safe altitude.
With each drop, the aircraft will glide 16-17m forward. Thus, from the engine failure at an altitude of 10,000m until landing, the aircraft can go another 160km.
This allows the pilot to fly the aircraft to the nearest airport for an emergency landing. Thus, flying higher will help the aircraft save, safer and faster.
Besides, flying at an altitude of 10km above sea level will prevent the aircraft from hitting birds in the sky. Civil aircraft models can reach speeds over 900 km / h. Striking a bird could be equivalent to hitting a flying bullet at 1,220 km / h.
On January 15, 2009, a US Airway Airbus 320 1549 landed in the Hudson River after hitting a bird just after taking off from LaGuardia airport, New York.
US Airway 1549 aircraft had to land in a river after hitting a bird.
So why doesn't the plane fly higher and faster than the upper limit?
The higher you fly, the thinner the air. Therefore, the aircraft must accelerate to receive enough air to help lift the wings. At some point, the cruising speed will be equal to the speed of sound. This broke the sound wall, creating shockwaves, destroying commercial aircraft structures.
There are some aircraft designed to fly faster than the speed of sound. However, these aircraft were for scientific and military purposes and not for passenger use, except for the Concorde aircraft from France and the Tu-144 of the Soviet Union. After a number of accidents, both of these aircraft were discontinued.
In addition, if flying in thin air, the engine of the aircraft will not have enough oxygen to ignite. As the air density decreases, the thrust of the engine also decreases.