Geometry

Question 1

Definition: chordline

Answer 1

straight line between leading edge and trailing edge

Question 2

Definition: chord

Answer 2

length of the chordline

Question 3

Definition: angle of attack

Answer 3

angle between chordline and the direction of airflow

Question 4

Definition: camber/meanline

Answer 4

line that is always midway between the upper and lower surfaces of airfoil

Question 5

Definition: mean chord ( ̅c )

Answer 5

value for the average chord distance along wing

Question 6

Definition: gross wing area

Answer 6

all the area of the wings, including that which would go through the plane

Question 7

Definition: Wing span

Answer 7

distance from one wing tip to the other

Question 8

Equation linking mean chord, gross wing area and wing span

Answer 8

gross wing area = mean chord x wing span

Question 9

Aspect ratio

Answer 9

Mean chord

Question 10

Meaning of a high aspect ratio

Answer 10

long slender wings - optimal for glyders

Question 11

Meaning of a low aspect ratio

Answer 11

short stubby wings - optimal for high speed and highly manoevarable a/c

Question 12

Definition: true airspeed (TAS)

Answer 12

speed relative to the air (not ground)

Question 13

Definition of dynamic pressure

Answer 13

pressure due to moving air

Question 14

Equation for dynamic pressure

Answer 14

1/2 . ρ . V^2

Question 15

Definition: Equivalent airspeed (EAS)

Answer 15

the airspeed at sea level that would give the same dynamic pressure that the true air speed would at the actual altitude

Question 16

Equation to find EAS

Answer 16

Ve^2 = V^2 . ( ρ / ρo )

where ρo = density at seal level