Fundamentals Of Flight Flashcards
Acceleration
Rate of change of speed and or velocity of matter with time.
What is motion?
The act, or process, of changing place or position; motion is movement.
Speed
Rate of movement in terms of distance measured in an allotted amount of time.
Velocity
Quickness or speed of an object in a given time and direction.
Newton’s first law
First law of motion, inertia, an object at rest will remain at rest, or an object in motion will continue in motion at the same speed and in the same direction, until acted upon by an outside force.
Newton’s second law
Second law of motion, force, states that if an object moving with uniform speed is acted upon by an external force, the change of motion, or acceleration, will be directly proportional to the amount of force and inversely proportional to the mass of the object being moved.
Newton’s third law
Third law of motion, action and reaction, states that for every action there is an equal and opposite reaction.
Bernoulli’s principle
When a fluid flowing through a tube reaches a constriction or narrowing of the tube, the speed of the fluid passing through the constriction is increased and its pressure decreased. The general lift of an airfoil is dependent upon the airfoils ability to create circulation in the air stream and develop the lifting pressure over the airfoil surface. As the relative wind strikes the leading edge of the airfoil, the flow of air is split. Part of the air is deflected upward and aft, and the rest is deflected down and aft. Since the upper surface of the wing has camber, or a curve, the flow over its surface is disrupted, and this causes a wavelike effect to the wing. The lower surface is relatively flat. Lift is accomplished by the difference in the airflow across the airfoil.
What is lift?
The force that acts, in an upward direction, to support the aircraft in the air. It counteracts the effects of weight. Lift must be greater than or equal to weight if flight is to be sustained.
Weight
The force of gravity acting downward on the aircraft and everything on the aircraft.
Drag
The force that tends to hold an aircraft back. Drag is caused by the disruption of the air about the wings, fuselage or body, and all protruding objects on the aircraft. Drag resists motion.
Thrust
The force developed by the aircrafts engine, and it acts in the forward direction. Thrust must be greater than or equal to the effects of drag in order for flight to begin or be sustained.
Longitudinal axis (roll)
An imaginary reference line running down the center of the aircraft between the nose and the tail.
Lateral axis (pitch)
An imaginary reference line running parallel to the wings.
Vertical axis (yaw)
An imaginary reference line running from the top to the bottom of the aircraft.
Fixed wing: ailerons (roll)
Longitudinal access
Elevators (roll) stabs
Lateral axis
Rudder (yaw)
Vertical axis
Rotary cyclic stick (roll/pitch)
Tilts the angle of the rotor blades to give the helicopter it’s directional motion by changing direction of the lift.
Tail rotor
This component counter acts torque of the main rotor by increasing or decreasing the amount of horizontal thrust the tail rotor produces, this movement is around the vertical axis.
Leading/trailing edge flaps
Creates extra lift by lengthening the top section of the wing resulting in maximum lift to reduce takeoff runs and landing rollout.
Spoiler
Used to decrease wing lift by destroying the smooth flow of air over the wing surfaces, this creates a more predictable landing glideslope.
Speed brakes
Hinged or moveable control surfaces used for reducing the speed of aircraft.
Slats
Movable control surfaces attached to the leading edge of the wing. When open, a slot is created between the slat and the wing leading edge. High energy air is introduced into the boundary layer of the top of the wing. At low airspeeds, this improves the lateral control handling characteristics, allowing the aircraft to be controlled at airspeeds below the normal landing speed. Known as boundary layer control.
Unique flight terms: Collective
rotating two or more blades collectively to create lift.
Angle of attack AOA
The angle at which the airfoil or fuselage meets a flow of air.
Autorotation
A method of allowing a helicopter to land safely from altitude without using engine power. As a helicopter is descending in altitude the collective is lowered allowing the reverse airflow through the rotor to maintain RPM. When the helio reaches a predetermined altitude the collective pitch is increased to convert inertial energy into lift to reduce the rate of descent and cushion the landing.
Basic aircraft hydraulic system
Reservoir-to hold a supply Pump-to provide a flow of fluid Tubing-to transmit the fluid Selector valve- to direct the flow Actuating unit- to convert fluid pressure into useful work
Landing gear main components
Shock strut assembly-absorbs the shock that otherwise would be sustained by the airframe.
Tires
Allows the aircraft to roll easily and provides traction during takeoff and landing.
Wheel brake assembly
Used to slow and stop the aircraft. Also used to prevent the aircraft from rolling while parked.
Retracting and extending mechanism
All necessary hardware to electrically or hydraulically extend and retract the landing gear.
Side struts and supports
Provides lateral strength/support for the landing gear.
