Air Density and Its Effects of Aircraft

Abstract

Air density is a major component that allows aircraft to fly. It is also always changing due to temperature, altitude, humidity, and atmospheric pressure. When the air density is reduced so too is aircraft performance. Pilots are responsible for keeping up with these changes and knowing how to use the aircraft's performance charts to adjust for these changes in the air.

Air Density and its Effects of Aircraft

Aircraft require a few standard things in order to make it fly. A power source to create thrust and a wing to create lift are two primary functions that make flight possible. However without air neither is possible. The air is not a constant value, it relies on temperature, altitude, humidity, and atmospheric pressure to create it density (EAI). When this density is decreased, so too is the engine and aerodynamic performance to the aircraft.

Reduced air density affects the production of lift to the aircraft. This is due to fewer molecules of air per volume of air that are allowed to flow around the wing which generates lift (Ali). Low air density also effects engine performance. With a lower density the mixture of air to fuel is lower which creates a lower fuel consumption rate. Due to the lack of lift and thrust available aircraft may require more runway during takeoff, and once in the air more time to climb to altitude.

Once factor of air density is the outside temperature. As the temperature increase the air becomes less dense due to the air molecules moving at high rate. The air becomes more erratic and the engines have a harder time creating the proper mixture for fuel consumption and thrust (Ali).

One way to overcome a lower air density environment is to have a turbocharger or supercharger installed on the engine(s). These devices are used to condense the atmospheric air to obtain a more useable density of air (Ali). This helps the engine produce a better mixture quality of fuel and air as well.

When the atmospheric air becomes more dense the aircraft is able to take advantage of the thicker air and create better power available and more lift. Since air density is not a constant throughout a fly, constant monitoring and adjustments to flight instruments are required. A pilot should also be familiar with the performance charts of the airplane which he is flying and know