Ever wonder if the altitude at which an airplane flies affects its speed? Most commercial jets have a cruising altitude of 31,000 to 42,000 feet. After taking off, they will climb for about 10 minutes to reach this altitude.
Yes, Altitude Affects Speed
There’s a direct connection between an airplane’s altitude and its speed. Engine power aside, the higher an airplane’s altitude, the faster it will fly.
Air Density
Airplanes fly faster at higher altitudes because of density. As an airplane climbs and its altitude increases, it will be exposed to less dense air. The air becomes thinner and less dense at higher altitudes. Not only does this improve fuel efficiency; the less dense air allows airplanes to fly faster.
The speed at which an airplane flies is heavily influenced by drag. High drag and low propulsion will result in slow speeds. The air molecules are more spread out at higher altitudes than at lower altitudes, resulting in less drag. With less drag, airplanes can fly faster at higher altitudes.
Weather Conditions
Another reason airplanes fly faster at higher altitudes involves weather conditions. Most airplanes — especially commercial jets — can withstand bad weather. Thanks to protective features like static sticks or rods, they can even handle lightning strikes. Nonetheless, pilots will often try to avoid bad weather by flying at higher altitudes.
Storms and pockets of turbulent air create drag, which as previously mentioned, counters propulsion. By flying at higher altitudes, airplanes can often go over storms and turbulent air. Airplanes will avoid the bad weather while subsequently flying faster.
IAS vs TAS
It’s important to note that an airplane’s altitude only affects its true airspeed (TAS) and not its indicated airspeed (IAS). IAS, of course, is the speed referenced by the IAS indicator. It uses a tube on the airplane’s exterior to measure the speed or impact of air molecules.
TAS, on the other hand, is the speed at which an airplane is actually flying. TAS represents the speed of the airplane relative to the mass of air through which it’s flying. As the airplane climbs, its TAS will typically increase. The airplane’s IAS, though, will remain the same.
In Conclusion
It’s not a myth; airplanes do, in fact, fly faster at higher altitudes. The air is thinner and less dense at higher altitudes, meaning airplanes are exposed to less drag. And with less drag, as well as avoiding bad weather, airplanes can fly faster.
FAQs
Air Density
At what altitude do planes fly fastest? ›
That said, planes generally fly at higher altitudes — usually between 30,000 to 42,000 feet — because the air gets thinner the higher you go. When the air is thinner, planes can fly faster and more efficiently, using less fuel to maintain the speed required to develop lift. However, the air must not be too thin.
Does altitude affect air speed? ›
As well as wind, temperature, and altitude also impact true airspeed. When altitude or air temperature increases, the density of air decreases and the true airspeed increases. This is because there is less air to put up resistance against the aircraft moving forward, so the aircraft moves faster through the air.
Does altitude affect flight time? ›
At higher altitudes, the air is thinner and provides less lift, which can reduce the speed of the aircraft and increase flight time. Planes generally fly at their optimal cruising altitude for fuel efficiency and speed, and deviations from this altitude can impact flight time.
What are the advantages of flying higher? ›
As the altitude increases, there is typically less unfavorable weather. The air gets thinner as the altitude increases, which means that there are lower chances of encountering bad weather. Per PrivateFly, the thinner air also allows the jet to fly faster and arrive at its destination quicker.
Why don't commercial planes fly higher? ›
As a result, the FAA effectively limits commercial passenger flight to 42,000′. Above that altitude, the pilots would be unable to control the plane in an emergency because they would have insufficient oxygen to breathe, even on pure oxygen. Why get up there in the first place? Efficiency.
Is it better to fly at high or low altitude? ›
Air Density
Airplanes fly faster at higher altitudes because of density. As an airplane climbs and its altitude increases, it will be exposed to less dense air. The air becomes thinner and less dense at higher altitudes. Not only does this improve fuel efficiency; the less dense air allows airplanes to fly faster.
What does coffin corner mean in aviation? ›
Coffin corner (also known as the aerodynamic ceiling or Q corner) is the region of flight where a fast but subsonic fixed-wing aircraft's stall speed is near the critical Mach number, at a given gross weight and G-force loading. In this region of flight, it is very difficult to keep an airplane in stable flight.
Why is it harder to fly at higher altitudes? ›
To the pilot it is the reduced air pressure at altitude which is the responsible mechanism in the production of this condition. As the air becomes less dense find the ambient pressure diminishes, there is a lessening of the driving force behind the available oxygen in the atmosphere.
Is there less turbulence at higher altitudes? ›
In summary, the NASA programs have indicated that : 1) For the higher flight altitudes (40,000 to 75,000 ft) turbulence is both less frequent and less severe than for the lower altitudes (20,000 to 40,000 ft). Turbulence appears to be present at the high altitudes less than 1% of the time.
Temperature at 35000 feet : -56.2 °F.
At what altitude can planes no longer fly? ›
Commercial passenger planes can fly as high as 41,000 - 43,100 feet, this is called the aircraft's service ceiling.
What happens if plane flies too high? ›
If an airplane flies too high, it can experience a number of problems, including: The air is thinner at high altitudes, which means that there is less oxygen available for the passengers and crew. This can lead to oxygen deprivation, which can cause headaches, dizziness, and even unconsciousness.
At what point is flying better than driving? ›
Opt for flying if:
You'll spend more time driving than you will at your destination. You enjoy flying and it fits with your budget. You need to get somewhere ASAP and driving isn't fast enough.
Do bigger planes fly better? ›
Former airline pilot Lenny Lee told Newsweek: "A larger, heavier airplane that's flying in a steady state will be harder for turbulence to shake, rattle and roll than a smaller, lighter airplane."
How does a jet engine get oxygen at high altitude? ›
Both piston engines and jet engines are able to work at altitude, within limits, because both compress the air which they suck in. Compression causes the same volume of atmospheric air to contain more molecules of oxygen, which then is mixed with fuel and burned.
What is the most efficient altitude to fly at? ›
Fuel Efficiency: Aircraft are designed to be most fuel-efficient within certain altitude ranges. For commercial jets, this range typically lies between 30,000 and 40,000 feet.
Why would a plane fly at 24000 feet? ›
1 Answer. This is typical for short hops. High cruise altitudes are good for fuel efficiency and to get a higher speed over the ground. However, it takes a lot of fuel to get to 30,000ft and it may take more fuel and time to get up to that altitude than would be saved cruising at that altitude given the short distance.
Is it easier to go faster at higher altitudes? ›
Key Takeaways: Running at a higher altitude feels more difficult because the air is thinner and contains less oxygen. As a result, your body doesn't have as much oxygen to pass to your muscles as they work.
What is the air temperature at 35000 feet? ›
At typical cruising altitudes and speeds, the aircraft skin experiences a temperature of approximately -13 degrees F (-25 degrees C). The outside air temperature at 35,000 ft (10,600 m) may read about -67 degrees F (-55 degrees C).
