Airplanes have several important factors that determine how they fly, the basis for which is Lift, Thrust, Weight and Drag. Weight is always in the downward direction, toward the earth, and lift is usually in the opposite direction of the weight, except when upside down when the lift will be in the same direction of the weight. Thrust is always in the forward direction, and drag is always in the opposite direction.

The different parts of the airplane aid in these basic forces. These are listed below:

Propellers

Propellers are a common form of propulsion in smaller aircraft.  They push the aircraft forward by acting like a fan, pushing air backwards.  The pushing action has an equal an opposite reaction, propelling the plane forward.  This provides the thrust necessary to propel the plane and the velocity needed to generate lift.

Jet engines

Jet engines also work under Newton's third law of motion, that all actions have equal and opposite reactions.  Jet engines expel air, and the resulting reaction pushes the airplane forward.  A jet engine contains a gas-powered turbine engine; the combustion that powers the engine produces gasses which are expelled out a nozzle at very high speeds (around 1300 mph) to produce thrust.  The turbine itself also pushes air out, generating more thrust. 

Airplanes have several important factors that determine how they fly, the basis for which is Lift, Thrust, Weight and Drag. Weight is always in the downward direction, toward the earth, and lift is usually in the opposite direction of the weight, except when upside down when the lift will be in the same direction of the weight. Thrust is always in the forward direction, and drag is always in the opposite direction.

The different parts of the airplane aid in these basic forces. These are listed below:

Wings and Wing Shape:

The basic shape of the wing, also called the airfoil, is often shaped with a flat base and a curved top ending in a point at the end. This is only the standard airfoil design, as there is several other types. The first is shaped like a tear drop, with the round part facing the front of the plane, and the point facing the rear, and is common on stunt planes. Another is diamond shaped. This type of airfoil design is common on supersonic airplanes.

The "Angle of Attack" of the wing controls the thickness of the slice of air that it is taking, therefore controlling lift. While this is not the only factor that controls lift, it is still one of them.

Flaps:

When taking off, airplanes need a great amount of speed to lift into the air. Then, when landing, they need to dramatically reduce their speed. For both of these instances, different airfoils would be required. Hence the invention of flaps. Flaps are attached at the end of the wings, and are movable up and down. To take off, they are extended rearward, and to land, they are extended downward. This will alter the shape of the wing, effectively allowing for speed control during take off and landing. While in the air, these cause drag, and are retracted to allow for a smoother flight.

Slats:

These are the same things as flaps, except they are attached to the front of the wing, instead of the back. They alter the shape of the wing allowing for speed.

Cylinders and Spheres:

While not often used, a rotating cylinder or sphere can be used to create lift. While the cylinder won’t be able to cause lift by itself, if it rotates, it is able to take a layer of air with it as it rotates, creating a difference in pressure between the top and the bottom, also resulting in lift. This is called the Magnus effect, and a good example is a curve ball.

If a cylinder is attached, and air is blown out of a long slit, it will force some air downward, thereby creating a difference in pressure, and create extra lift. Some of the tail rotors on helicopters were replaced with these.

Engine:

After the wing, the most important part is the engine. Attached to an engine is either a jet, or a propeller. These provide thrust forward. A propeller uses the basic principals of the wing as far as shape and design go. The angle of attack increases along the propeller. Some of the more advanced three and four blade propeller engines have it so the pilot can adjust the Angle of Attack to control speed and altitude.

Landing Gear:

Landing Gear usually consists of wheels that allow the plane to land. On smaller planes the landing gear is fixed, by on larger planes, such as airliners, they are retractable to reduce drag.

Stabilizers:

On the tail of the plane, there are 2 small wings called stabilizers. Both of these wings are symmetrical airfoils that allow the pilot to change the direction of the plane. Flaps are placed on these back airfoils to allow the pilot to control lift and drag.

Tail Wings:

There are two types of tail wings on the back of the plane, the horizontal and the vertical. The Horizontal wings control lift and drag using stabilizers. The vertical wings control the angle of attack of the plane, and shift the plane left and right.

Ailerons:

Ailerons are used to keep the plane level. They are attached the end of the wing to achieve this.

Pilot Tube:

The pilot tube is a L-Shaped Tube on the top of the Cockpit. Air enters this tube and creates pressure, allowing the airspeed gauge to function.