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POF 1 (Equations (Load Factor = L/W In Climb: Load Factor = cos Ɣ In…

- - - - The pressure differential between the upper and lower surfaces - the driving force for the vortex
        
        The greater the pressure differential the greater the amount of lift being produced
        
        High Aspect Ratio (long span) have weaker vortices cos flow as to travel so far, press diff is less
        
        Fly faster = lower AoA = lower Lift = smaller vortices
      - The amount of the time the driving force is given to operate on the air mass
        
        the longer the CHORD the greater the diving force for the vortex
        
        Therefore sweepback has smallest vortices at tip!
      - Summary: In short, the strongest vortices are produced by an aircraft that is HEAVY, CLEAN, and SLOW.
        
        Weight = More Lift
        
        Clean = Higher AoA = more lift
        
        Slow = Higher AoA = more lift
    - - Downwash
      - Drag (lift induced drag)
- - - - AoA
      - Thickness
      - Camber
- - - - Boundary layer
        
        Laminar
        
        thin, slippery and low energy.
        
        prone to seperation
        
        @ Transition point turns to turbulent flow which is thick, draggy and high energy
        
        1-2mm thick.
        
        Flow is parallel to the surface
        
        Speed changes in the boundary layer are gradual low Reynolds number 1/2million i.e. viscous forces predominate
        
        Turbulent
        
        Is a thicker layer ~1-2CM thick
        
        Flow moves in many directions
        
        Air at higher speeds is mixing within and between the layers (of the BL):
        
        less prone to separating from the surface
        
        Creates more skin friction drag due to both greater and greater mixing
        
        Relatively high Reynolds number
        
        Turbulent flow delays separation
        
        Transition Point
        
        Laminar flow turns turbulent
        
        NOT SAME as Point of Separation
        
        Never aft of the pt of max thickness
        
        Moves forward as AoA increases
    - - The static pressure at from stagnation pt <> rear so will cause form drag rearward
- - - - Induced
        
        Caused by Lift (Vortices and the downwash)
        
        Proportional 1/V²
        
        Influences:
        
        Speed
        
        AC Weight
        
        Manoeuvre
        
        Reduced by:
        
        Tip Mods
        
        Higher Aspect Ratio
        
        Decrease Speed (less lift)
      - Parasite = Profile + Interference
        
        Not related to LIFT!!!
        
        Proportional V²
        
        Profile = Form + Skin Friction
        
        Form Drag
        
        Cause: Pressure differential
        
        Proportional V²
        
        Reduced by:
        
        Streamlining
        
        Decrease Speed
        
        Decrease X-Section
        
        Skin Friction Drag
        
        Shear forces (Boundary Layer)
        
        Reduced by:
        
        Smooth Surface
        
        Decrease Speed
        
        Decrease Surface Areas
        
        Interference Drag
        
        Mixing Airflow
        
        Reduced by:
        
        Fillets
        
        Decrease Speed