AVIT 323 Block 1
Explain Newton's third law in relation to lift
"For every action there is an equal and opposite reaction" The air that flows over the wing is forced downwards by the airfoil, the equal and opposite reaction of the air is to push upwards, which causes lift
A 15 lb bowling ball is dropped off a 90 ft building. What is the potential energy at the instant of impact?
0 ft-lbs (all energy in the object is lost on impact to other factors)
Name the two elements of P-Factor
1. AOA Differential 2. Relative Wind
What is Mach Tuck?
As an aircraft approaches the speed of sound it creates a shockwave and its wing center of pressure moves aft. As it moves aft, it creates a pitch down moment which there by increases airspeed and worsens situation
What is Force Divergence?
At a speed above M-Crit, airflow will begin to separate from the wing similarly to during a stall. Increases Drag exponentially.
High-lift devices tend to do one, two, or all of three things. Name them.
1. increase in camber 2. increase in surface area 3. increase in energy
What is your L/D max?
An AOA
What is Newton's first law?
An object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force.
Explain the two causes of adverse yaw
Caused by both Ailerons (upward and downward facing) Form drag anytime you force anything to change directions
During a Chandelle, what should the power be set to?
Enter 100 KIAS, then full power
At any point of the objects fall (15 lb bowling ball off of a 90 ft building), what is the total energy?
Ep= w x h 1350 ft-lbs = 15lb x 90ft
What is the definition of a stall?
Exceeding your critical angle of attack Poor AOA control
Why do we not see human-powered airplanes as common transportation methods?
Human muscles are not made to produce the such high power and endurance that is required for flight
What gives you airspeed?
Forward Acting Component of Lift and Forward Acting Component of Weight
What makes up total energy? Explain each item
Kinetic Energy -> energy in motion Potential Energy -> stored energy
What is the most common cause of an unintentional spin?
Slip during a stall
What causes an accidental spin?
Side-Slip during a stall
Why should your first clearing turn be made to the left?
To account for right of way rules, aircraft over-taking you will be flying to your right
True or False During a Chandelle, the first half is changing pitch, the last half is changing bank
True
True or False Over-banking tendency happens partially because the raised wing is traveling at a higher speed than the lowered wing
True
(My airplane has a published Vs of 55 and a max gross weight of 3800 lbs) I've overloaded my plane to 4100 lbs. What is my new stall speed?
Stall = Vs sqrt (Wactual/Wmaxgross) 57 KIAS = 55 sqrt (4100/3800)
(My airplane has a published Vs of 55 and a max gross weight of 3800 lbs) What is the new stall speed when I pull 1.3 G's?
Stall = Vs sqrt(n) 62 KIAS = 55 sqrt (1.3)
Explain each item of the lift equation (L=1/2p V^2 CL S)
p: air density (energy of motion of the slipstream) V: velocity CL: coefficient of lift (AOA/airfoil shape) S: surface area (airfoil size)
Turbulent airflow....
is aerodynamically dead
Whats Newton's second law?
(F= m x a)
My airplane has an IAS speed of 110 KTS and I'm in an 8 KT wind. What is my pivotal altitude if my elevation here is 745 ft?
(GS^2/11.3) + Elevation Upwind: (102^2/11.3) + 745 = 1665 MSL Downwind: (118^2/11.3) + 745 = 1977 MSL
(My airplane has a published Vs of 55 and a max gross weight of 3800 lbs) If I pull back too far and stall at 72 KIAS, how many G's are on the plane?
(IAS/Vs)^2 (72/55)^2 = 1.71 G's
Name the three corrections for left turning tendencies that manufacturers often build into an airplane
1. Offset Engines 2. Offset Fin 3. Angle of Incidence Differential
Name the four turning tendencies of a propeller-driven airplane
1. P-Factor 2. Torque 3. Slipstream 4. Gyroscopic Precession
When are you most likely to see P-Factor?
1. Slow Speeds 2. High Angle of Attack
Requirements for profit
1. Travel fast (depreciation costs) 2. Fly below the speed of sound (force divergence) 3. Coolest air possible 4. Shouldn't fly one foot higher than necessary
How is VGLIDE determined?
By flying the aircraft and testing it through trial and error
During a steep turn, name the two turning tendencies that pull the nose to the left
P-Factor and Torque (slow airspeed, high angle of attack)
What makes up total pressure?
Static pressure and Dynamic Pressure
Draw and label the types of force
1. Compression 2. Tension 3. Shear
Draw and label the types of flow
1. Divergent 2. Convergent 3. Shear
My indicated airspeed is 77 and my descent rate is 550 fpm. What is my finesse ratio?
Finesse = (IAS x 100) / sinkrate 14 = (77 x 100) / 550
If I am at a 40-degree bank angle, will my load factor increase or decrease if I double my IAS?
It will not change
What causes over-banking tendencies?
Lateral component of lift on the raised wing is greater than the vertical component of lift on the lower wing Outer wing turns faster than inner wing (speed differential)
How is angle of attack measured?
The angle between the chord line and the relative wind
What causes a side-slip?
Uncoordinated Flight
Work Equation
f x d = w