2: Theory of Flight

The four forces acting on an airplane in flight are:

• Thrust, Drag, Power, Lift

• Thrust, Lift, Drag, Weight

• Drag, Airflow, Power, Gravity

• Lift, Power, Wind, Gravity

The curvature of the upper and lower surfaces of an airfoil is known as:

• wing shape

• drag ratio

• chord

• camber

Lift is created through a pressure differential on the wing. Which of the below is true?

• upper surface: lower speed, lower pressure

• lower surface: higher speed, lower pressure

• upper surface: higher speed, lower pressure

• lower surface: higher speed, higher pressure

A term used to describe the direction of airflow with respect to the wing is what?

• angle of incidence

• relative airflow

• angle of attack

• crosswind factor

The angle at which the airfoil meets the relative airflow is called what?

• crab angle

• angle of incidence

• degree of turn

• angle of attack

What are the two principle types of drag?

• induced, parasite

• induced, form

• parasite, skin friction

• skin friction, form

Which type of drag is caused by parts of an airplane which are active in the production of lift?

• parasite

• form

• inspired

• induced

Wingtip vortices tend to flow:

• out and down

• in and down

• out and up

• in and up

If the weight of the airplane is increased, the performance of the airplane:

• is increased

• will remain the same

• is decreased

• increases to the point of a stall, then decreases

What is the very thin sheet of air lying over the surface of the wing (think about the roof of your car)?

• transition layer

• boundary layer

• laminar layer

• transition point