How Airplanes Manipulate Air to Achieve Flight

By

Home / How Airplanes Manipulate Air to Achieve Flight

An airplane rolls, yaws, and pitches on an axis – Image by Auawise

For a common observer, looking at airplanes taking-off and approaching to land, the phenomenon seems quite simple – to the observer, it appears to be just a tiny bit more complicated than driving a car.

The truth: the pilot requires about the same amount of attentiveness as an automobile driver, but not all of the pilot’s attention is focused on the traffic outside. Instead, the pilot concentrates on the control panel in front of him, which indicates vital readings for the aircraft.

It hasn’t always been like this, however – it hasn’t always been quite so easy to fly a plane, and at the fundamental level, it still isn’t.

Pilots must contend with air – it’s all around us, and with its properties of density, temperature, fluidity, and compressibility, it is quite a marvel that planes of all sizes can maneuver within air and at various speeds, some crossing the speed of sound. But how do the various parts of a plane interact with, and manipulate, the air around them?

The Aircraft Wing – How It Interacts With Air

Airplane wings are the basic structures that support the weight of aircraft. This weight includes the weight of the fuselage, (main body and other attached airplane parts) along with the weight of passengers on board, and fuel being carried during flight.

The wing of an aircraft interacts with air, increasing the speed of the air flowing over it, and relatively slowing down the air flowing under the wing, which creates lift to support all that weight.

What are The Planes’ Rudders For?

The airplane’s rudders (attached to the vertical stabilizers) are there for steering the nose of the aircraft from left to right, which is a movement  known as yawing to pilots. The rudders utilize the flow of air beside them to aerodynamically ‘yaw’ the aircraft.

When the rudder moves right, the aircraft tail moves left, and the nose of the aircraft yaws, or moves, to the right. All of this rotation about the airplane’s center of gravity is the result of air manipulation by the rudder.

How do The Elevators Interact with Air?

Airplane elevators attached to the horizontal stabilizer of aircraft interact in a manner that is very similar to that of the plane’s rudder, except in an up and down motion, rather than left and right. Elevators can manipulate the air flowing over and under it.

If the pilot wants to pitch the nose up, he/she will pull back on the control column. The elevator moves up, and decreases the speed of air passing over the horizontal stabilizer. This generates an area of low pressure under the horizontal stabilizer (the faster the velocity, the lower the static air pressure will be) and the tail of the aircraft moves down as a result. Consequently, the aircraft pitches over its center of gravity, and the nose of the airplane lifts.

Steering an Aircraft Through the Air

Basically, each of the components of a plane works together to keep the plane moving in the right direction. Want to see how the airflow actually looks? Here’s a visual depiction of the air flow around an aerofoil (wings, rudders and elevators).

Resources

Aviation Theory Centre. Aeroplane General Knowledge and Aerodynamics. (2004).

Federal Aviation Administration. Pilots Handbook of Aeronautical Knowledge. (2008). Accessed July 15, 2012.

Federal Aviation Administration. Airplane Flying Handbook. (2004). Accessed July 15, 2012.

Oxford Aviation Services. Joint Aviation Authorities Airline Transport Pilot’s License Theoretical Knowledge Manual. (2001). Accessed July 15, 2012.

Leave a Comment