Aeroplanlære - Kap 3 (Lift) Flashcards
What is lift perpendicular too?
The relative airflow
What is airflow parallel too?
Drag
What is the aerodynamic force equation?
What increases with angle of attack?
Coefficient of lift
What is the lift equation?
What is the coefficient of lift?
Which factors affect coefficient of lift?
Angle of attack
Thickness
Camber
What increases linear with the pressure differential?
The coefficient of lift
What is the maximum of coefficient of lift for a particular aerofoil?
What is another word for the stalling angle?
Critical angle of attack
What happens when the thickness of an aerofoil increases?
The stalling angle of attack increase
The rate which CL increase is approximately the same
CLmax increases
What is the difference between a cambered aerofoil and a symmetrical when it comes to the coefficient of lift?
The coefficient of lift is higher on a cambered but stall angle is the same
What is the effect of a trailing edge flap on lift and stall angle?
It increases camber and thereby increase lift but also reduce stalling angle
Two identical aircraft but one is twice as heavy. Extra lift is needed and how do we do this?
Flying faster - 1.414 times faster
Increasing the coefficient of lift (CL)
When flying level which two forces are equal?
Weight (Gravity) and lift
When decreasing speed what must then be done to keep level flight?
Raise nose
What type of wings does a fighter jet have in order to fly level at high speeds?
Thin and less cambered wing to reduce the coefficient of lift (CL)
What is the different variables in the equation for lift measured in?
V is in m/s^2
S is in m^2
Air density is in kg/m^3
The answer will be in newtons
When does ground effect occur?
What is reduced in the ground effect?
Drag
Angle of attack
What is on the y axis?
Drag
What should you be cautious of in the ground effect when it comes to angle of attack?
The stalling angle is less so you will stall at a lower angle
When entering ground effect what can you expect?
When leaving ground effect what can you expect?
