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Why does flying at high altitudes save fuel?
Climbing to a higher altitude allows the jet to operate in thinner air, where fuel economy is better and drag is reduced for longer. Although it is counterintuitive, climbing to a higher altitude and then descending can save fuel.
Why do I get better gas mileage at higher altitudes?
Fuel economy improves at higher altitude in all engines because the pumping work is reduced. As you go up, a lower manifold vacuum is required to move the car. The lower vacuum means lower pumping work and the result is better fuel economy.
Are cars less efficient at altitude?
Reduced oxygen in high altitudes can lead to inefficient, sluggish engine performance because there is less air to feed the internal combustion engine. Generally speaking, an engine loses three percent of its rated power for every 1,000 feet of altitude gained.
Why do jet engines get better fuel efficiency at high?
Low density causes low drag and therefore the aircraft flies much faster at high altitude than on low altitude when it is given the same thrust. At this high speed, the mass flow through the engine is comparable to the mass flow at low speed in high density air (low altitude).
Why are jet engines not used at high altitudes?
High altitude air is less dense, making it easier to pass through. Oxygen content in high altitude is exactly the same as sea level. While the air up there is the same air we breath, there is less of that air in the same volume container. Space vehicles do not use jet engines.
Why is fuel efficiency lower at higher altitudes?
In reality, the total efficiency will be lower because we have not included propulsive efficiency, friction effects or power offtake by bleed air, pumps and generators. Propulsive efficiency describes how well the acceleration of air is performed.
Why does a jet engine have more drag?
A jet engine is very efficient at compressing air into the combustion chamber and can be designed for efficiency at specific operating altitudes. A jet airliner experiences more drag per unit of speed at altitude compared to lower altitude because the speed at altitude is higher.