AMT 280 Test 1A
Hypersonic Flight
5 times the speed of sound
Friction
A force that opposes motion between two surfaces that are in contact
When the lift of an airfoil increases, the drag will:
Also increase
The acute angle formed by the chord line of a wing and the relative wind is known as the
Angle of Attack
Lift varies
As the square of the speed.
The curvature of the wing surface is called the
Camber
The center of pressure is also referred to as the:
Center of Lift
Density of Air is Highest on:
Cool Dry Days
Flight Mach Number with First Indication of Sonic Flow
Critical Mach Number!
Unit Sound is Measured In
Decibels
As altitude increases, temperature will:
Decrease
Supersonic airflow passing through a constriction would be characterized by
Decreasing velocity, increasing pressure, increasing density
Specific Gravity
Density of an object relative to water. No units.
Parasite Drag
Drag induced when an object is moving through a viscous fluid.
A stall is the direct result of
Excessive Angle of Attack
Interference Drag is Reduced By:
Fillets and Fairings
Who Came up with Curvature That Affected a Body Moving Through Air?
Heinrich Magnus
The drag that results from the production of lift
Induced Drag
The resultant aerodynamic force on the airfoil
Intersects the chord of the wing at the center of gravity
As temperature decreases, what happens to speed of sound?
It decreases.
As Temperature increases, what happens to speed of sound?
It increases.
A low Reynolds number =
Laminar flow
The chord of a wing is measured from:
Leading edge to trailing edge
Velocity Squared =
Lift
______ Varies directly with the area of the wing.
Lift
______ varies directly with the density of air directly.
Lift
What causes mach tuck?
Migration of lift, Center of pressure on sweptback wings.
What happens to air molecules with sound?
Molecules vibrate
Lift acts
Perpendicular to the relative wind
Mach Number
Ratio of true airspeed to the speed of sound
Laminar flow is most likely to occur on an aircraft wing where the skin surface is:
Smooth
Airfoil
Surface body that responds to relative motion
Mass
The amount of matter in an object
Induced Drag
The drag that acts parallel to relative wind
Lift
The force that directly opposes the weight of an airplane and holds the airplane in the air. A component of the resultant force which acts perpendicular to the relative wind.
Airfoil Thickness
The height of the airfoil profile.
Boundary Layer
The layer of air immediately adjacent to the surface of an aerofoil.
Center of Pressure
The point on the surface of an object about which the object's surface area is centered.
The critical Reynolds number is used to predict
The point where airflow turns turbulent
The critical reynolds number is used to predict
The point where the airflow turns turbulent.
The Speed of Sound is
The rate at which pressure disturbances will spread through the air.
A wing obtains most of its lift from:
The reduced pressure above the wing due to the increase in velocity of flow over the top of the surface.
The net result of lift and drag vectors is:
The resultant force
Throughout most of the flight range of a typical airfoil, at the usual angles of attack, the CoP moves forward s the angle of attack increases and backward as the angle of attack decreases.
True
A high Reynolds number =
Turbulent flow!
The critical mach number of any airplane is reached
When any of the local flows around the wing reach the speed of sound.
Bernoulli's Principle
as the velocity of a fluid increases, the pressure exerted by the fluid decreases
