How High Do Commercial Airlines Fly? Everything Explained!

Want to know how high do commercial airlines fly? It’s a question many people think about those airplanes. Commercial airplanes don’t just fly at any height; they operate within a specific range for various reasons. They must be above mountains and most weather troubles, but also within an atmosphere that allows their engines to function correctly. 

In this article, you will learn about the heights these airplanes reach. Explore the concept of “cruising altitude” and know why it’s so important for a smooth and safe flight. This post will also inform you about the factors influencing how high a plane will fly on any given trip. So, get ready to learn all about the heights commercial airlines achieve!

How High Do Planes Usually Fly?

After takeoff, a commercial airplane climbs until it reaches its cruising altitude. The plane flies at this height for most of the trip, keeping a constant altitude and speed until it starts coming down to land. Usually, commercial airlines fly between 30,000 and 40,000 feet above the sea. But the exact height can change based on different things.

The Reasons Behind the Altitude

Commercial airlines fly so high for several good reasons. 

• First, the air up there is much thinner than near the ground. This thin air means less opposition, so the airplane engines don’t have to work as hard to keep the plane moving fast, which saves a lot of fuel for the airlines. 
• Second, most rough weather, like thunderstorms and strong winds, happens below 30,000 feet. By flying above these, airlines give passengers a smoother and more comfortable ride. 
• Third, when planes stay at steady altitudes within specific pathways, air traffic controllers can manage all the airplanes in the sky much more quickly and safely, keeping them well apart. 
• Lastly, the air is generally more unmistakable at these high altitudes, giving pilots better visibility and offering passengers fantastic views on a clear day.

Factors Controlling Flight Altitude

Even though planes usually fly between 30,000 and 40,000 feet, the exact height can change depending on a few factors. 

• A heavier airplane might start its trip flying lower and then climb higher as it uses up fuel and gets lighter. 
• Also, planes often fly higher for longer trips because the air is thinner up there, which helps them save more fuel. 
• Air traffic controllers also tell pilots which altitude to fly at to keep everyone safe and manage the flow of planes. 
• Pilots might occasionally ask to fly a little higher or lower to catch a good tailwind or avoid a strong headwind. 
• Yet, bigger planes that fly long distances usually cruise at the higher end of that altitude range than smaller planes used for shorter trips.

Units of Measurement

When discussing how high commercial airplanes soar, you’ll usually hear two main ways to measure it: feet and flight levels. Knowing what separates them and why pilots use both can help you understand how altitude works in flying.

Altitude in Feet

The easiest way to tell how high something is in the sky is to measure it feet from a starting spot. In flying, that spot is usually the average height of the sea, which we call Mean Sea Level (MSL). So, if you hear a plane is at 35,000 feet, it just means it’s 35,000 feet above the sea’s average level. Knowing this height in feet is a big deal when a plane takes off or lands. Those are the times when every little thing matters. Pilots need these exact numbers to ensure they’re at the perfect height above the runway and the nearby ground. Even when planes fly low around airports, feet are the trusty way to measure and keep everything running safely.

Flight Levels (FL)

When planes fly up into the sky, especially in busy areas with lots of air traffic, pilots use a handy system called flight levels to keep things simple and safe. It’s like an adaptable language that helps all pilots understand how high everyone is, no matter where they’re flying or what kind of plane they’re in. Once they climb past a specific point, usually around 18,000 feet, pilots set their altitude meter to a standard setting, like syncing everyone’s clocks. After that, they take their height in feet, drop the last two zeros, and that’s their flight level. 

Why Use Flight Levels?

The big reason they use flight levels is to keep things the same for everyone. Because all planes in busy air areas use the same standard pressure setting, air traffic controllers can easily ensure planes stay a safe distance apart up and down. It doesn’t matter what the air pressure is at any particular spot; this system helps controllers keep the skies safe and makes air travel work properly.

Why Both Feet and Flight Levels?

We use two main ways to talk about how high planes are flying. 

• When a plane is close to the ground, like when it’s taking off or landing, we usually talk about its height in feet. This tells pilots exactly how far they are from the ground. 
• But when planes are flying way up high, where there are many other planes, they use flight levels. This is like a special, shared way for all the pilots and air traffic controllers to talk about altitude. 
• It helps keep all the planes safely apart, even if the air pressure differs in different places. 
• So, feet are great for near the ground, and flight levels help keep things safe up high. Both ways work together to make sure every flight is safe.

Comparison to Other Types of Aircraft

Commercial airlines usually fly at an exact height that works best for their long passenger trips. But many other kinds of airplanes fly in the sky, and each has its own special job. 

Private Jets and Business Aircraft

These can fly at different heights. 

• If it’s a smaller and lighter private jet, it could fly at about the same height as regular airlines, or a little lower. 
• But if it’s a bigger and more advanced business jet, it can fly as high as or even higher than those big commercial airplanes. Sometimes they even go above 40,000 feet. 
• Flying up this high helps them save fuel, just like the airlines, and they can also fly above the busier air traffic down below.

General Aviation Aircraft 

Small airplanes for fun rides, flight lessons, or short trips fly much lower than big commercial airlines. 

• You’ll find them cruising between 5,000 and 15,000 feet. This lower height is acceptable because their trips don’t go as far. 
• Their engines might not be as strong as the ones on big jets, and many smaller planes don’t have the supplies to keep the air comfortable when they fly high. 
• Also, sometimes they must stay in specific areas controlled by air traffic. If people fly to enjoy or see the view, they don’t need to climb to super high altitudes.

Military Aircraft

There are all sorts of military aircraft, and each flies at its different altitude. 

• Fighter planes stand to go very, very fast and move around quickly. This makes them fly much higher than ordinary commercial airplanes, even as high as 60,000 feet for certain missions or when they must intercept other aircraft. 
• But sometimes they also get to fly low when they need to. Large combat aircraft that transport troops and equipment are roughly the same size as passenger aircraft. They tend to travel between 30,000 to 40,000 feet at similar altitudes because it’s most fuel-efficient when they fly long distances. 
• They made helicopters to fly near the ground, a few thousand feet off the ground.
• They primarily operate where regular airplanes cannot travel, so they do not need to fly that high.

Cargo Planes

Special cargo aircraft, usually flown by carriers such as FedEx or UPS, cruise at the exact altitudes as commercial passenger airlines. 

• They enjoy the same fuel efficiency and storm avoidance benefits as passenger aircraft. 
• Their exact altitude depends on their weight and flight distance.

High-Altitude Research Aircraft

Some special airplanes can fly way up high and way higher than usual passenger airplanes. 

• People use them for such purposes as science experiments, looking over things from up high, or taking covert photos. 
• There’s an airplane called the U-2 spy plane that can go more than 70,000 feet in the air! They do very specialized and specific work.

Commonly Asked Questions