POF day 3 Flashcards
When does lift act perpendicular to RAF
2D flow
When does lift act perpendicular to EAF
3D flow
What is the induced angle of attack
Angle between EAF and RAF
Where is the effective angle of attack found
Between the EAF and the chord line
What does the EAF in 3D lift cause
Induced drag
What does a low aspect ratio wing do for induced drag
Increases it because the vortices are allowed to be bigger
Why might having an efficient wing not be great?
It only helps with 1% of the flight where you are flying slow and it doesn’t consider practicality or flying at high speed
Explain vortex strength vs the wingspan
The closer to the body the weaker the vortex
Where will the wing stall first
Where the vorticies are weakest along with the effective angle of attack
What is interference drag
Caused by vorticies forming at junctions of different shapes/surfaces on the aircraft
How do reduce drag for form drag
Streamline
How do you reduce skin friction drag
A smooth surface
How do you reduce interference drag
Fillets
How do you reduce induced drag
Winglets or other wing mods
What is a winglet
Reduces the tip vortex strength
