Title: Why Are Jet Engines More Efficient at Higher Altitudes? – HighSkyFlying
Headings: Why Are Jet Engines More Efficient at Higher Altitudes?
Why Are Jet Engines More Efficient at Higher Altitudes?
Table of Contents
Operation of Jet Engine at High Altitude
The Air Is Cooler
Less Drag
Flying at a High Altitude Improves Thermal Efficiency
Optimum Cruise Altitude
Safety Considerations for High Altitude Flights
Practically, ‘high altitude’ operations are any operations at levels above FL250 (25,000 feet)
Above this FL250 altitude, the following features begin to take on increasing importance:
To check these challenges, pilots:
Do Planes Use More Fuel at Lower Altitudes?
Conclusion
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Content: Hence, the larger the expansion of the air when heated, the faster the aircraft moves because it is the expansion of air that drives the turbines of the jet engine which generates more power for lesser fuel burn. Less Drag
Also, at high altitude, there is low drag because the density of air is now lower than it was at a lower altitude. Given the same thrust, this low drag causes the aircraft to fly much faster at high altitude than at low altitude. Likewise, the quantity of energy needed to heat air to adequate temperature is comparable between both altitudes. The amount of power generated at high altitude is higher because the aircraft is flying at a much higher speed here than at low altitude (Power = Thrust x Speed). Generally, the cooler and less dense air at high altitude the less the fuel to air mixture in the combustor, thereby improving fuel efficiency. In addition, flying at a high altitude provides thermal efficiency for the engine. Flying at a High Altitude Improves Thermal Efficiency
The thermal efficiency cycle of a jet engine is determined by the temperatures of the incoming air and the outgoing air. The lower the temperature of the incoming air, the higher the efficiency. Air at a high altitude has a lower density and lower temperature.