If you regularly travel by air, you may notice that flights take less time when traveling East in the United States. You can fly between the same two cities on the West and East Coast. Flights to the East Coast, however, will typically take less time than flights to the West Coast. Why does this happen exactly?
How the Jet Stream Affects Flight Times
The reason Eastward flights take less time is because of the jet stream. Consisting of a high-altitude air current, the jet stream plays a major role in flight times, especially for long routes.
The jet stream is located at an altitude of about 30,000 to 40,000 feet — the same altitude at which commercial airliners fly. It consists of fast-moving air that moves from West to East. It’s not uncommon, in fact, for jet stream winds to reach speeds of up to 200 mph.
When airplanes travel from the West to the East, they are flying in the same direction as the jet stream. Therefore, they will experience less drag. The jet stream will actually “push” airplanes Eastward, resulting in shorter flight times. The opposite is true when flying from the East to the West. Airplanes flying in this direction will be going against the jet stream, resulting in more drag and longer flight times.
A Global Phenomenon
The jet stream isn’t limited to the United States; it’s a global phenomenon. There are four primary jet streams: one near the North Pole, one near the South Pole, and two near the equator.
Whether you’re taking a flight in the United States, Europe or any other country, you’ll probably encounter one of these jet streams. And because the air in jet streams moves Eastward, it will affect flight times.
How Much Does the Jet Stream Affect Flight Times
You might be wondering just how much of a difference the jet stream has on flight times. Several factors affect the jet stream’s impact on flight times, such as the location of the jet stream, the altitude, weather and more. With that said, flight times between the United States and Europe can vary by up to 20% depending on whether the airplane is flying Eastward or Westward.
In Conclusion
It may sound strange, but the direction in which airplanes fly can affect their flight times. Airplanes typically fly faster when traveling from the West to the East. This is because the jet stream — a current of fast-moving air — travels in this same direction.
