Part 2: Principles of Flight Flashcards
What is Newton’s 3rd Law?
To every action, there is an equal and opposite reaction.
What is Bernouili’s Principle?
As airspeed increases, air pressure decreases
in straight and level flight at constant speed, which forces are in balance?
Weight = Lift; Thrust = Drag
What is the angle of attack of a wing?
The angle between the chord line of the wing and the oncoming air
Where does air flow faster around a wing?
Over the top
How much lift is generated by the top of the wing?
Up to 80%
Where is the greatest effect of lift on the wing?
Nearer the front edge of the wing
What is the relationship between air flow and lift?
Lift is at 90 degrees to air flow
How does drag vary in relation to airspeed?
The square of airspeed: 2 x airspeed = 4 x drag
What are the three planes of movement?
lateral, longitudinal, normal
What controls a plane’s pitch?
Elevators
What controls a plane’s roll?
Ailerons
What controls a plane’s yaw?
Rudder
What are dihedral wings?
Wings angled upwards (to create lateral stability)
What are anhedral wings?
Wings angled downwards
What do trimming tabs do?
Cancel out forces on flight controls
What do flaps do?
They adjust lift and drag created by a wing (by changing its shape)
What degree of flap give the best increase in lift?
30-60 degrees
What degree of flap gives maximum drag?
90 degrees
What are slats?
At front of wing, reduce stalling speed
What is the critical angle of attack?
15 degrees (after this stalling is likely)
What forces act on a glider?
Weight, drag and lift
How does a glider speed up?
Lowers the nose
How does a glider slow down?
Using airbrake
Suggested better answer by Katie Nixon:
A glider slows down by pitching nose up (using airbrakes only increases the rate of descent)
What control makes a helicopter produce lift?
Collective pitch control
What control makes a helicopter move forwards/backwards and side to side?
Cyclic pitch control
What undesirable effect is generated by helicopter rotor blades?
Torque reaction
What counters the torque reaction in helicopters?
Rudder pedals
What control makes a helicopter rotate?
Rudder pedals
What is angle A?
The angle of attack
Where is air pressure lowest?
At point B (where airflow is the fastest)
What is this aircraft doing?
Pitching
What is this aircraft doing?
Rolling
What is this aircraft doing?
Yawing
What is happening in the bottom diagram?
The plane is stalling (note angle of attack is 16 degrees, one degree more than the “critical” angle of attack).
This diagram shows a plane pitching, rolling and yawing + their controls.
These are done across which three axis?
Pitching across the lateral axis.
Rolling across the longitudinal axis.
Yawing across the normal (or vertical) axis.
The diagram shows the three axes. What is movement across each of these called?
Movement across longitudinal axis = rolling.
Movement across lateral axis = pitching.
Movement across normal axis = yawing.
