Aero Flashcards
What is Force?
Push or Pull exerted on a body (mass x acceleration)
What is Mass
Quantity of Molecular Material
What is volume?
Amount of space occupied
What is density?
Mass/volume (mass per unit of volume)
What is moment?
Force applied a distance from a pivot point (fulcrum)
What is weight?
Force on a mass toward the Earth (G)
Kinetic Energy
Energy of Motion (KE = (1/2)MV^2
What happens to air density and temperature as altitude increases?
Both decrease
What atmospheric properties affect pressure?
Density and Temperature
What is total pressure
Static + dynamic pressure (Pt = Ps + Pd)
What is true altitude?
actual height above MSL
What is pressure altitude
Height above a standard datum plane (29.92 inHg)
What is density altitude
Pressure altitude corrected for temperature (Index for gauging engine performance, not used as actual height reference)
What is Indicated Airpseed (IAS)
Airspeed read from airspeed indicator
What is calibrated airspeed (CAS)
IAS corrected for instrument error
What is equivalent airspeed?
CAS corrected for compressibility (significant near the speed of sound)
What is True Airspeed (TAS)?
Velocity through the air mass
What is groundspeed
TAS corrected for winds
What is Mach Number?
TAS/Speed of Sound
What is critical mach number?
Speed where there is the first evidence of local supersonic flow
What happens to TAS and Mach Number in a constant IAS Climb?
Increases (TAS- approximately 3 knots/1000 feet
What are the three airplane axes?
Longitudinal, Lateral, Vertical
What are the motions about axes?
Roll, Pitch, Yaw
What is adverse Yaw?
Tendency for the aircraft to yaw opposite the direction of roll
Aileron corresponds to which axis?
Roll (Longitudinal)
Elevator corresponds to which axis?
Pitch (Lateral)
Rudder corresponds to which axis?
Yaw (Vertical)
What is Wingspan?
Length wingtip to wingtip
What is chordline
Infinite line through leading and trailing edges
What is chord
Width of wing, length from leading edgge to trailing edge
What is average chord
average of all chords
What is wing area
Wingspan x average chord
What is wing loading?
Weight/area
what is aspect ratio?
wingspan/average chord
What is angle of Incidnence?
Angle between chordline and longitudinal axis
What is dihedral angle?
Upward slope of wing from root to tip
What is relative wind?
Airflow experienced by aircraft or airfoil
what is Angle of Attack?
Angle between relative wind and chordline
What is the Mean Camber Line (MCL)?
Line halfway between airfoil upper and lower surfaces
What is camber?
Distance between the MCL and Chordline
What is Positive Camber?
When the MCL is above the chordline. Produces lift at 0 degrees AOA
What is the Aerodynamic Center?
Point on chordline where changes in aerodynamic forces take place (AKA the center of lift)
What is Spanwise Flow?
Flow parallel to the leading edge of the wing
What is chordwise flow?
Flow perpendicular to the airfoil
How are lift, weight, thrust, and drag related in level unaccelerated flight?
opposing aerodynamic forces are balanced (equal)
How are lift, weight, thrust, and drag related during the takeoff roll?
Weight is greater than lift, thrust is greater than drag
What is the center of gravity (CG)?
Point where weight is concentrated
What are the results of the CG being too far aft?
Tail Heavy
What are the results of the CG being too far forward?
Nose Heavy
Changing which factor in the lift equation will affect lift the most?
Velocity
How does a pilot change lift?
Primarily: AOA and Velocity
Secondarily: Adjusting Camber (changing shape of the wing)
What are the two parts of aerodynamic force due to airflow over the wing?
Lift and Induced Drag
What is total drag
Parasite drag + Induced Drag
What happens to parasite drag and induced drag as velocity increases?
Parasite drag increases
Induced drag decreases
What are the three types of parasite drag?
- Form
2.Friction - Interference
Which parasite drag is the difference between static pressures of the leading and trailing edges?
Form
Which parasite drag is turbulent flow in the boudnary layer?
Friction
Which parasite drag is due to mixing airflows between components?
Interference
Describe the effects on lift and drag caused by lowering the flaps to Takeoff (TO)?
Big increase in lift, little increase in drag
Describe the effects on lift and drag caused by lowering the flaps to Landing (LDG)?
Little increase in lift, big increase in drag
What drag increases as Gs increase?
Induced