Stalling Flashcards
What must increase to maintain level flight at low speed?
Angle of attack
Why must angle of attack increase at low speeds?
To increase Lift Coefficient and compensate for loss in dynamic pressure
Steep adverse pressure gradient and loss of kinetic energy results in what?
Boundary layer separation from wing upper surface and stall
Stall causes what to increase and what to decrease?
Increase in drag and decrease in lift
Which produces a greater loss in energy, a sharp or large radius leading edge?
Sharp leading edge
When is adverse pressure gradient greatest?
Pressure difference over wing upper surface is large and distance is short
Separation point on a cambered wing as angle of attack increases
Moves forward
What increases the pitch down moment at the stall?
Increased arm between CP and CG due to aft movement of CP
CLMAX
Maximum value of CL or stalling (critical) angle of attack
If stalling angle is exceeded, what then decreases?
Lift coefficient
What creates downwash?
Vortices
Downwash changes the direction of what?
Direction of relative airflow
Direction of flow a wing experiences
Effective AirFlow (EAF)
Relationship between downwash, EAF and effective angle of attack
Less downwash = shallower EAF = larger effective angle of attack
What determines CL and therefore the stall?
Effective angle of attack
