Jet Speeds Uncovered: How Fast Do Commercial Airplanes Fly?

In this article we’ll answer the common question, how fast do planes fly.

The average cruising speed for a long-haul commercial passenger aircraft ranges from approximately 880 to 926 km/h. Or 475 to 500 knots and 547 to 575 mph.

However there are a lot of factors that go into how fast commercial aircraft fly. In this article we’ll go over all of these factors but before we do, here’s the flight speeds of many common commercial aircraft.

What Impacts the Speed of a Plane?

Airplane speed is a confusing subject because airplanes operate in the atmosphere, which is itself moving around.

When driving down the road in your car, your speed is a simple matter of miles per hour (or kilometers per hour, outside the US). But pilots and aircraft designers think about a lot more.

Fundamentally, the speed that matters to airline route planners and passengers is the speed the plane flies across the ground from Point A to Point B.

This is known as the ground speed.

This is exactly like driving your car, and the math is easy. If you go 60 mph for three hours, you’ll go 180 miles toward your destination. Ground speed is the airspeed of a plane with tailwinds added or headwinds subtracted.

Inside the cockpit, however, the pilot and plane are worried about how much air moves over the wings.

This measurement is called airspeed, and there are a few different types. True airspeed vs indicated airspeed.

True Airspeed (TAS) is the most accurate because it accounts for the air temperature and density, which changes with weather and altitude. Aircraft have airspeed gauges, but they often show Indicated Airspeed (IAS), which is less accurate and needs to be corrected.

How Is a Plane’s Speed Measured?

Aviators use nautical miles for measuring distance, which are different than the statute miles used in the US highway system. 1 NM is approximately 1.15 SM and one nautical mile per hour is called a “knot.” Therefore, aircraft speeds are typically reported in knots, not mph. 

Jets have limitations on their design—they can’t fly too slow, but they also can’t fly too fast. Typical commercial airplanes are not designed to fly faster than the speed of sound, also known as Mach 1.

If they get too fast, the air begins forming shockwaves along the wing that can cause the aircraft to become uncontrollable. The speed they cannot exceed is called the Maximum Mach Number, or the Mmo. 

How fast you’re flying in terms of Mach numbers requires some math, so a machmeter is included in planes where this is an issue.

A machmeter means the pilot can see that they are not exceeding the Mmo without thinking about all the math. As a result, when a commercial airplane is flying at altitude, it is flying at a safe designed Mach number. 

You might see the speeds of aircraft counted in either knots or Mach. 

Different Speeds During Flight

It’s important to realize that aircraft don’t always fly at the same speed. For one thing, there’s a speed limit in the sky. All aircraft below 10,000 feet must slow down to 250 knots or less. Near busy airports, they must slow to 200 knots or less. 

But beyond that, all aircraft have flight profiles that are followed on every flight. The pilots set the most efficient climbing, cruising, and descent settings.

Climb Speeds

Getting to a safe altitude as quickly as possible is always a priority because more altitude means more choices should there be an emergency or a loss of power.

This means getting off the runway with the best rate of climb, which will give you a lot of altitude quickly but at a slower forward speed. 

However, the pilot will transition to a more efficient climb profile once the plane is at a safe altitude.

This means lowering the nose, reducing the engine power, and getting more forward speed at the expense of a slower climb rate. 

Cruise Speed

The flight’s cruise phase is also done using a pre-arranged profile.

The pilot will set a desired engine power (and fuel burn) for the given flight, and the resulting airspeed or Mach number will determine their ground speed and range. 

When looking at the cruise speed numbers above, you’ll notice that most airliners are remarkably similar in performance.

A Maximum Mach number of 0.9–0.95 is about all that is possible in a sub-sonic transport aircraft. This is because air is accelerated as it flows over some parts of the aircraft. So even though the plane’s speed is less than Mach 1, some airflow over parts of the plane is much closer to the speed of sound.

Without making the entire aircraft capable of supersonic flight, these planes are limited to somewhere around this speed. 

What’s more, the air is far less dense at altitude than it is near the surface. Jet engines operate very efficiently there, but the aircraft’s wing does not.

It must fly very fast to have enough air flowing over it to avoid stalling.

For this reason, many airliners operate in a small window between fast enough to not stall and slow enough not to exceed the Mmo. The result is that many airliners today are flying around at roughly the same speeds. 

At cruise speeds aircraft will sometimes have to change their speeds when flying through turbulence.

Descent Speeds

So, how fast do commercial aircraft fly during the descent?

Commercial planes make two types of descent: a cruise descent and a landing approach. Cruise descent means losing altitude without building up too much forward speed and exceeding their Mmo.

There is little change in their forward speed since they just reduce engine thrust and let gravity do the rest.

Descending through 10,000 feet means abiding by the 250-knot speed limit.

This requires less power and perhaps drag devices like air spoilers to slow the aircraft down. Since less air flows over the wings as it slows down, the pilot will use flaps to increase the lift the wings can make.

Approaching the airport means slowing down as much as possible while maintaining control of the aircraft. Most planes are shooting approaches at 150 knots or less.

This requires using wing flaps and other high-lift devices to maintain control.

Supersonic Air Travel

So how fast do commercial planes fly if they’re going at supersonic speeds?

“I wanna go fast.” -Ricky Bobby

No discussion of commercial airplane speeds would be complete without mentioning the Concorde.

The world’s only supersonic airliner flew in regular service from 1976 to 2003 for Air France and British Airways. The plane provides insight into why many modern commercial airplanes look and perform as they do today. 

The Concorde set several records and logged more supersonic hours than any other aircraft before or since.

In 1996 a British Airways “Speedbird” flew from New York to London in 2 hours, 52 minutes thanks to a 175 mph tailwind. In 1992 and 1995, the same Air France Concorde set records circumnavigating the globe (east and westbound, albeit with many fuel stops each way). The quickest was the 1995 eastbound trip which was done in 31 hours, 27 minutes.

Only 20 Concordes were ever built, and while flying on the special plane was a sign of status, supersonic air travel never really took off.

For one thing, the plane was a gas guzzler and very expensive to operate. For another, the sonic booms it produced meant that it could only ever fly at those airspeeds over the open ocean. That made its feasibility for legs like New York to Los Angeles virtually nill.

New technologies may be changing the math, however. Several startups have begun designing new SSTs (supersonic transports, as the Concorde was called).

These new designs, built with modern techniques and computer-aided design, aim to reduce the sonic boom impact and improve fuel economy. Boom Supersonic has been making headlines with its planned Overture airliner and has secured orders from United and American Airlines.

While it hasn’t flown yet, the projected cruise speed of the Overture is Mach 1.75, making a flight from London to New York in about 3 hours, 30 minutes.