Forces Of Flight Flashcards
(23 cards)
When are the four forces in equilibrium?
Unaccelerated flight
What is the Lift equation?
L = (1/2)(ρv²)(S)(CL)
What are the two types of stalls?
- Slow Speed
- Accelerated Stall
When does a slow speed stall happen?
Slow but High AoA like Takeoff or Landing
When does an accelerated speed stall happen?
Sudden rapid increase in AoA
How can you increase Lift Coefficient (CL)?
- Shape of the airfoil
- Angle of Attack
How can you increase the critical angle of attack?
- Add slot
- Add slat
What does stalls depend on?
ONLY by AoA
If we want to increase AoA, should we decrease or increase velocity?
Decrease
Which is more when climbing, Thrust or Drag?
T > D
Which is more when landing, Thrust or Drag?
D > T
What is the relationship of Aspect Ratio?
Length and Width of a wing
If you want good gliding, what should be big?
Aspect Ratio
What is Angle of Incident?
Tiny AoA even when airplane is on the ground
What does wing twist or washout do to prevent bad stall characteristics?
Stalls at the wingtip first then at the root
What drag happens in low speed but high lift?
Induced drag
What drag happens when more speed increases the air hitting the wing/junction?
Parasitic Drag
How to calculate Total Drag?
Induced Drag + Parasitic Drag
When will ground effect occur?
At a height equal to the wingspan of the aircraft
What happens during ground effect when entering?
- Induced drag low
- Nose-down pitching
- Decrease AoA
- Airspeed Indicator read low
What happens during ground effect when leaving?
Opposite to Ground Effect of entering
Why don’t we use full flaps when taking off?
It slows the plane down too much
If airspeed increases by x3, how much does drag increase by?
x9
