Principles of Flight 1 Flashcards
What are the Four Forces of Flight
Lift, Weight, Thrust and Drag
What conditions are required for Straight and level unaccelerated flight
When a plane maintains is Heading, Altitude and Airspeed
What is happening in Straight and Level Flight
Lift = Weight and Thrust = Drag
a wing is a type of what
Airfoil
What is an Airfoil
any surface that generates an aerodynamic force as a fluid
What shouldn’t we confuse Fluids with
Liquids
What is a Fluid
Any substance that deform under an applied stress
What are types of fluids
Liquids, Gas and Plasma
What is the most forward part of the wing
Leading edge
What is the most Aft Part of the wing
Trailing Edge
What is a Chord Line
The imaginary line drawn between the Forward and Aft part of the wing
What is the Flight Path
Path of the planes flight through the air
What is Relative Wind
The Airflow that flows around the plane as it travels through the Air
What relationship does the Relative Wind have with the Flight Path
The Relative Wind is Parallel too but opposite to the Flight Path
What is the Angle of Attack
The Angle between the wings Chord line and the aircraft’s relative wind
What two major theories acting in unison create lift
- Newtons 3 Laws 2. Bernoullis Principle
What is Newtons 1st Law
A Body at rest remains at rest until acted on by an outside force
What is Newtons 2nd Law
Force = mass x acceleration
What is Newtons 3rd law
For ever action there is an equal and opposite reaction
According to Newtonian Physics what is air doing when it hits the wing
Deflects down
What is the Bernoulli Principle (Stated)
As the Velocity of a fluid increases, its internal pressure decreases
As Airspeed Increases, what happens to its internal pressure
Decreeses
What is the Pressure difference around the wing
Low Pressure = top of wing, High Pressure below the wing
What is the pressure difference known as
Pressure Gradient
How does air always move within pressure Gradients
From High to Low
How does the Pressure gradient contribute towards lift
the High Pressure Air moves towards low pressure
What factors are included in the Lift Equation
Air Density,
Surface Area of the Wing,
Velocity,
Co-efficient of Lift
Coefficient of Lift takes into consideration two things what are they
Airfoil Shape & Angle of Attack
The Faster the Plane travels_______
the more Lift the wings will generate
The higher the angle of attack_______
the more lift the wings will generate
What is the Planform of a wing
Shape of the wing when viewed from above
What is the Camber of a wing
Curvature of the wing
What is the Aspect Ratio of the wing
The relationship between the Length and the width
What is the Wing Area of the Wing
Total Surface area of the Wing
What are used that alows Pilots to Manipulate the wings and change their shape and are important for Landing and Take off
High Lift Devices
Initially Flaps will increase the lift by a 1)_____amount with only a 2)_____increase in drag, as the flaps are extended further lift 3)_____only slightly and 4)_____increases significantly
1) larger 2) Small 3) Increases 4) Drag
The Weight force always extends and pivots from the _______
“Center of Gravity” also known as its “CG”
How does the Weight of an Aircraft decrease during flight
As Fuel is burned
What is Thrust
the forward acting force opposing Drag which propells the plane forward
Where do planes generally get their thrust from
Propellars or Turbo Engines
Propellar is an airforce, true or false
True
What is Drag
Drag is the force opposing thrust which limits the forward speed of an aircraft
What are the two types of Drag
Parasite and Induced
What is Parasite Drag
A direct result of Air resistance as the plane travels through the air
What are the 3 types of Parasite Drag
Form, Interference and Skin Friction
What effect does Parasite Drag have on the Aircraft
As the speed of the Aircraft increases, the parasite drag will also increase
What is induced Drag
As the Wing creates lift it is also creating Vortices that spiral from the bottom of the wing to the top
When is Induced Drag increased
at slower airspeeds (and decrease as we increase speed)
What is one way to experience reduced Drag
Through Ground Effect
What is Ground Effect
the increased lift and decreased drag that an aircraft’s wings generate when they are close to a fixed surface.
What does Ground effect do to the Aircraft when taking off
makes the plane lift off before the regular take off speed
WHat is L/D
L/D MAX - the lift-to-drag ratio, is the amount of lift generated by a wing, divided by the aerodynamic drag it creates by moving through the air.
What is the Co-Effiecient of Lift
a number that’s used compare the performance of airfoils and wings.
