Ground Effect

Question 1

At what height does ground affect start to take place

Answer 1

1 wingspan from the ground

Question 2

What height does ground effect start to have a significant effect

Answer 2

1/2 a wingspan from the ground

Question 3

How does ground effect work

Answer 3

Downwash behind aircraft = suppressed by ground = less downwash p less induced angle = bigger effective angle = higher AOA = more lift

Question 4

How does the drag curve move during ground effect

Answer 4

Down and left

Question 5

What effects will you feel during ground effect

Answer 5

Aircraft floats (due to less drag)

Aircraft balloons (due to increased lift)

Question 6

How does ground effect affect pitch

Answer 6

Pitch down

Suppressed downwash = not as much downwash onto stabiliser = less downforce from tailplane = nose pitch down

Question 7

What happens what you enter ground effect

Answer 7

Induced drag decreases = float

Lift increases

Stalling angle of attack reduces

Nose pitch down

ASI under reads

Question 8

What happens as you exit ground effect

Answer 8

Induced drag increases

Lift decreases

Stalling AOA increases

Nose pitch up

ASI reading goes back to normal

Question 9

What effect does ground effect have on wing tip vortices

Answer 9

Reduces them