Everyone knows that the bigger the radius of a circle the greater the circumference. Hence, an airplane must cover a greater distance between 2 points when it cruises at a higher vs lower altitude.
So why don't airlines save money and fly at lower altitudes?
The higher you are, the better chance that people die when the bomb goes off.
Weather
Airlines fly at the most fuel/time efficient altitude possible. They have to take into account the weight of the plane, distance, winds, etc, in order to burn the least fuel and get there the fastest.
It's all about the Benjamins. $$$
lower gravity, less work
just kidding. i'd guess it'd have something to do with less air resistance (thicker air near the Earth).
air is less dense the further you go up, so the plane flies more efficiently. Also, it would be really annoying to have a huge roar from an airplane every time one goes over our heads. You can't hear them when they're really high.
Airplanes don't fly at lower altitude because it would be stupid to waste fuel.
Grouper wrote:
Everyone knows that the bigger the radius of a circle the greater the circumference. Hence, an airplane must cover a greater distance between 2 points when it cruises at a higher vs lower altitude.
So why don't airlines save money and fly at lower altitudes?
Miller, tell me, I bet you do your best thinking on the bus?
Airplanes can fly much faster at higher altitudes than at lower.
For giggles, let me walk you through this. If you flew at 15000' rather than 30000' on a trip around the world you,d travel 2*pi*15000 less, or 17.85 miles -- about 2 minutes time saved on a trip around the world.
Did a light bulb go on yet?
it would be wasteful wrote:
Airplanes don't fly at lower altitude because it would be stupid to waste fuel.
Well, if it's so fuel efficient to fly at high altitude, why do they take off so low to the ground?
Air Density lowers the higher you go so you can go faster with the same thrust.
In addition to other good reasons that have been adduced: it's generally less choppy/bumpy at higher altitudes--a smoother ride.
Combination of things, most of them already listed.
First is the lack of ability for private planes to reach high heights in a practical manner. Commercial airplanes fly at 32,000+ feet because they can fly at that height more easily and thus stay out of the way of private traffic.
Less turbulence at such a high height as well, making for efficient air travel.
Less noise pollution.
I'm sure the reasons go on after that, but this is coming from an individual with limited flight experience.
Oregon grad wrote:
Well, if it's so fuel efficient to fly at high altitude, why do they take off so low to the ground?
Well posed, sir!
There is one exception, if are close enough to the ground you can benefit from the ground effect. You have to be about one wingspan from the ground to get this effect but it can make flying for efficient.
Um, ever hear of chemtrails?
by definition you have to take off _from_ the ground.
Legal pressure from the Audobon Society.
They have to get up high enough to get away from the turbulance of the giant treadmill from which they took off.
You also have to consider that the higher they are up there, the further apart they are. If they were lower, they would be in each others' turbulence and vectoring around each other all the time.