Four Forces Of Flight

How Does A Plane Fly
There Are Four Forces Of Flight
Vertical Axis
Longitutinal axis
Lateral Axis
** Warning This Section Is Pretty Long **
This is the Lift Equation
L=C  (D x V^2) x A
We can change the Cl, V^2, and A
Cl = The shape of the wing
V^2 = The Speed at which we fly
A = Our surface area of the wing changed by flaps
To better understand lift we can turn to the Bernoulli Principle the old way of thinking about lift 
This is the Bernoulli's Principle
pressure : High
velocity : Low
pressure : High
velocity : Low
pressure : Low
velocity : High
This is the Bernoulli's Principle Applied To A Wing
Lower Pressure
Higher Pressure
On This Wing, We Can See That The Air Below, Since It Is Not Disturbed It Stays At A Higher Pressure Than The Air Having To Travel Faster Over The Wing.
Although this is a good way to understand and apply Bernoulli's Principle there is a new and improved idea called the Turning Theory.
So The Turning Theory is where we have air hitting the wing and getting deflected off of it and in a downward direction. With Newton's Third Law Of Motion, we will have an equal and opposite reaction to our applied force meaning the air is forced downward and the wing is kept up in the air. Now you might be thinking how does this work if we are flying parallel to the wind?
And the culprit to that answer is we don't actually fly directly parallel into the wind we have something called AOA or
Angle Of Attack
So What is AOA?
the definition of AOA is the angle between the relative wind and the chord line of the wing
(an imaginary line that is drawn through the middle of the wing).
Thrust: The Force That Moves The Plane Foward.
Thrust opposes drag and is created by the power plant of our aircraft.
(Power Plant is Described in the PPL Information Page)
What Comes With Thrust?
There are four turning factors: P-Factor, Spiraling Slip Stream, Torque, and Gyroscopic Precession.
Side View
P-Factor is when you change the pitch of the aircraft and the propeller blade to the relative wind in this case we have the blade that is pitched up say like when you're taking off this is a left-turning tendency because the propeller now acts as a partial wing with one side taking a bigger bite of air.
Top-Down View
This happens to the right side of the propeller because of the direction the propeller turns. The right side creates more thrust than the left side of the propeller in turn it pushes the plane to yaw to the left.
Gyroscopic Precession
Side View
Top View
More prominent in tailwheel / conventional gear aircraft the gyroscopic precession states that if there is a force applied to a spinning gyro the force will act 90 degrees to the right of the point of application.
Now in Tri Gear Aircraft this is a right turning tendency and is less worry some than flying a tail wheel aircraft.
Spiraling Slip Stream
Spiraling slipstream is when the aircraft produces thrust and the air keeps moving around the aircraft ultimately pushing on the left side of the vertical stabilizer yawing the nose to the left and the tail to the right.
(Pretty Self Explanitory)
Torque happens when we initially apply power either in a climb or for takeoff.  BUT!! as everyone knows "Newton" has his Third Law Of Motion in which he states that for every reaction there is an equal and opposite reaction. So in this diagram, we can see the Blue acting as the initial force (Note* we are viewing this from the front of the aircraft) which pulls the airplane to the right but if we look Red is the equal and opposite reaction to the initial force and in conclusion, we turn to the left instead of to the right.
Weight: The Force That Brings Us Down To Earth.
Weight opposes Lift.
Weight is a component that has to do with the load factor and how much your plane's wings can withstand the forces.
What is load factor?
Load factor is the 

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