Weight and Balance
This is the point where an aircraft would balance if suspended.
What is the center of gravity?
This force moves an aircraft forward through the air.
What is thrust?
This force opposes motion through the air.
What is drag?
These tendencies are strongest during takeoff due to high power and low airspeed.
What are left-turning tendencies?
This factor of lift increases exponentially because it is squared in the lift equation.
What is velocity (airspeed)?
This is the product of weight multiplied by its distance from the datum.
What is a moment?
This law explains why pushing air backward creates forward motion.
What is Newton’s Third Law?
Lift acts in this direction relative to the relative wind.
What is perpendicular?
This force causes a rolling motion opposite the rotation of the propeller.
What is torque reaction?
These wing devices increase surface area and lift during takeoff and landing.
What are flaps and slats?
This imaginary reference line is used to measure all arms in an aircraft.
What is the datum?
A propeller is this type of aerodynamic structure.
What is an airfoil?
This is the airflow direction opposite the aircraft’s motion.
What is relative wind?
This spiraling airflow strikes the vertical stabilizer and pushes the nose left.
What is the corkscrew effect (spiraling slipstream)?
This happens to air density as altitude and temperature increase.
What is it decreases?
When an aircraft is too heavy, takeoff distance increases and this decreases.
What is climb performance (rate/angle of climb)?
The twisting of a propeller blade helps distribute thrust evenly along its length.
What is blade twist (changing angle of attack)?
This happens when airflow separates from the wing at a critical angle.
What is a stall?
This gyroscopic property causes forces to act 90° ahead in the direction of rotation.
What is precession?
This aerodynamic condition occurs when angle of attack becomes too great and lift rapidly decreases.
What is a stall?
This happens when weight is too far aft, making stall recovery difficult or impossible.
What is reduced stability / nose-up pitching tendency?
This type of propeller allows the blade angle to change for efficiency at different speeds.
What is a variable-pitch (or constant-speed) propeller?
Increasing velocity increases lift by this mathematical relationship.
What is squared (velocity squared)?
This effect is caused by unequal thrust from the propeller blades at high angles.
What is P-factor?
Because of reduced air density, aircraft at high-elevation airports require more of this during takeoff.
What is runway length (or takeoff distance)?