aero space i hate myself
### Unit 1
Categories of aircraft for certification purposes:
- Airplane
- Rotorcraft
- Glider
- Lighter-than-air
Certifications a pilot needs for an airline:
- Private Pilot License (PPL)
- Commercial Pilot License (CPL)
- Airline Transport Pilot License (ATPL)
- Instrument Rating (IR)
- Multi-Engine Rating (MER)
### Unit 2
Empennage + components:
- Empennage: The tail assembly of an aircraft, providing stability and control.
- Vertical stabilizer (fin)
- Rudder
- Horizontal stabilizer (tailplane)
- Elevator¹
Composite construction materials reasons we use them:
- High strength-to-weight ratio
- Corrosion resistance
- Fatigue resistance
- Design flexibility
- Reduced maintenance costs²⁶
weight
What should a pilot do if a plane becomes rapidly depressurized:
- Don oxygen masks immediately
- Initiate an emergency descent to a safe altitude (usually 10,000 feet)
- Inform air traffic control
- Ensure passengers are using oxygen masks³²
UAS materials:
- Carbon fiber composites
- Aluminum alloys
- Plastics
- Titanium¹⁴
### Unit 3
Humidity and its effect on air density:
- Humidity decreases air density because water vapor is less dense than dry air¹¹.
Definition of viscosity:
- Viscosity: A measure of a fluid's resistance to deformation or flow⁴.
Standard day air pressure and temperature defined as:
- Pressure: 1013.25 hPa (29.92 inHg)
- Temperature: 15°C (59°F)
High density altitude vs low density altitude on propeller:
- High density altitude: Reduced propeller efficiency due to thinner air.
- Low density altitude: Increased propeller efficiency due to denser air.
Components of density altitude and how it's calculated:
- Components: Pressure altitude, temperature, and humidity.
- Calculation: Adjust pressure altitude for non-standard temperature.
Tendencies of a fluid over a convex surface known as ____:
- Coanda effect
Factors that decrease/increase density altitude:
- Decrease: Lower temperature, higher pressure, lower humidity.
- Increase: Higher temperature, lower pressure, higher humidity.
Why are we concerned with density altitude:
- Affects aircraft performance: Takeoff distance, climb rate, engine power, and aerodynamic efficiency.
### Unit 4
Forces as vectors - two components:
- Horizontal component
- Vertical component¹⁷
When we change AOA how does that affect the wing:
- Increased AOA: Increases lift up to a critical point, then causes a stall.
- Decreased AOA: Reduces lift²³.
Coefficient of lift in the lift equation and the components:
- Lift equation: \( L = C_L \cdot \frac{1}{2} \rho v^2 S \)
- \( C_L \): Coefficient of lift
- \( \rho \): Air density
- \( v \): Velocity
- \( S \): Wing area
Relationship of drag, weight, lift, and thrust in level flight:
- Lift = Weight
- Thrust = Drag
Lift on a wing definition regarding relative wind:
- Lift: The force generated perpendicular to the relative wind due to pressure differences on the wing surfaces.
Bernoulli's principle:
- Bernoulli's principle: An increase in the speed of a fluid occurs simultaneously with a decrease in pressure or potential energy of the fluid.
Advantages of a variable pitch propeller:
- Optimizes blade angle for different flight conditions
- Improves efficiency and performance
- Reduces fuel consumption
Factors that will increase lift on an airfoil:
- Increase in AOA (up to critical point)
- Increase in airspeed
- Increase in wing area
- Increase in air density
Regard to stall how does load factor affect stall speed:
- Increased load factor: Increases stall speed.
Relation of stall speed and angle of attack for aircraft:
- Stall speed: The minimum speed at which an aircraft can maintain level flight.
- Angle of attack: The angle between the chord line of the wing and the relative wind. Stall occurs at a critical AOA.
Newton's third law regarding thrust:
- Newton's third law: For every action, there is an equal and opposite reaction. Thrust is the reaction force that propels the aircraft forward.
Definition of AOA in terms of chord line and relative wind:
- AOA: The angle between the chord line of the wing and the direction of the relative wind.
How to reduce induced drag:
- Increase wingspan
- Use winglets
- Optimize wing shape
Coefficient of drag definition with AOA:
- Coefficient of drag (Cd): A dimensionless number that describes the drag force on an object relative to its size and speed. It varies with AOA.
Airspeed affects parasitic drag:
- Parasitic drag: Increases with the square of airspeed.
Center of gravity is determined + equations:
- Center of gravity (CG): The point where the total weight of the aircraft is considered to be concentrated.
- Equation: \( CG = \frac{\sum (weight \times arm)}{\sum weight} \)
### Unit 5
Inherently unstable aircraft effects:
- Requires constant control inputs
- More maneuverable
- Used in fighter jets for agility⁸
Purpose of various flight control surfaces:
- Ailerons: Control roll
- Elevators: Control pitch
- Rudder: Control yaw
- Flaps: Increase lift during takeoff and landing
Main function of flaps reasons why we use them:
- Increase lift and drag
- Allow for steeper descent angles without increasing airspeed
- Reduce landing and takeoff distances
Designs to make an aircraft more maneuverable:
- Canard configurations
- Delta wings
- Thrust vectoring
Controls on a helicopter do:
- Cyclic: Controls pitch and roll
- Collective: Controls lift
- Anti-torque pedals: Control yaw
Pitch, roll, and yaw - what axis do they rotate:
- Pitch: Lateral axis
- Roll: Longitudinal axis
- Yaw: Vertical axis
How quadcopters counter torque:
- Opposing pairs of rotors spin in opposite directions
The three axes of flight:
- Longitudinal axis (roll)
- Lateral axis (pitch)
- Vertical axis (yaw)
What a trim tab is:
- Trim tab: A small adjustable surface on a control surface used to maintain a desired flight attitude without constant control input.
What characteristics add to stability:
- Dihedral wings
- High wing configuration
- Center of gravity forward of the center of lift
Velocity relative to lift:
- Lift increases with the square of velocity