I hope I convey my point probably, but why do planes go so many thousands of feet in the air? Is it faster that way, or could they achieve similar flight times at a lower altitude?
Does it have something to do with the curvature of the earth?
In: Engineering
1. Less air = use less gas to go fast
2. Although it takes extra energy to go up, much of that is recovered on the way down
3. It’s a little safer — if you lose power you have much longer to solve the issue or get to a runway
4. Quieter over houses
It’s not a perfect analogy, but iImagine running with a 300 mph wind in your face vs a 25 mph. A much thinner atmosphere makes travel much easier
In addition to the fuel efficiency reason the air is much less turbulent in that layer of air than it is in the layer with almost all the clouds and weather.
It’s faster because there’s less air resistance but since the diameter is about 12.740 km, adding 10 km more wont change the curvature almost at all. So commercial planes can fly farther using less fuel. Other types of airplanes cruise at different altitudes and speeds.
They don’t need to but at higher altitudes there’s less air so you use less fuel, planes could easily fly lower but their efficiency would drop
Less air = less air resistance. Less resistance = easier, meaning usually faster and needs less fuel
Radius of earth is 3963 miles. Calculate 1/4 arc length by multiplying by 1.57 = 6222 miles. Diameter of earth is roughly 24,901miles, divided by 4 is 6225 miles so that match checks out.
Add 40,000 feet (7.58 miles) and recalculate gives a quarter arc of 6234 miles.
So you add roughly 12 miles (0.2%) to a trip a quarter of the way around the earth by travelling at 40,000 feet.
climbing the extra 15k feet adds a pretty negligible amount of straight line travel and time. if you only climb to 15k and I climb to 30k, I’m probably going to get there first unless you burn a lot more fuel to just barely beat me there.
Low in the atmosphere you get lots of drag but also lots of lift. This is best for underpowered planes such as small prop planes.
Very high in the atmosphere has extremely low drag but also poor lift. This is best for aircraft designed to travel above the speed of sound.
Around 30-40 thousand feet is the sweet spot for commercial airliners. It strikes the right balance of drag to lift.
It’s also safer to fly above 20k feet. If anything goes wrong, you have more time to respond.
You ever hear a jetliner from the ground? Imagine them being any closer
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