
Lift
Equation Answers
Step 1.
Using FoilSim, change the values for Area only. Pick 5 different
values for the wing area. Record the values you used for area and the
resulting lift.
Answers will vary.
Step 2.
Graph your recorded data for wing area and lift below.
The graph should show a direct relationship.
Step 3.
State the relationship between area and lift.
The graph should show a direct relationship.
Step 4.
Using FoilSim, change the values for Altitude only. Reset the airfoil
conditions to the original values given. Pick 5 different values for
the altitude. Record the resulting values for density and the resulting
lift.
Answers will vary.
Step 5.
Graph your recorded data for density and lift below.
The graph should show a direct relationship.
Step 6.
State the relationship between density and lift.
The graph should show a direct relationship.
Step 7.
Using FoilSim, change the values for Velocity (airspeed) only. Reset
the airfoil conditions to the original values given. Pick 5 different
values for the velocity. Record the values you used for velocity and the
resulting lift.
Answers will vary.
Step 8.
Graph your recorded data for velocity (airspeed) and lift below.
The graph should show a direct relationship
with the square (curved line). It may help to complete a second graph
of lift vs. velocity squared.
Step 9.
State the relationship between the velocity and the lift.
The graph should show a direct relationship
with the square (curved line). It may help to complete a second graph
of lift vs. velocity squared.
Step 10.
Using the lift equation, calculate the lift generated by an aircraft
flying at 10,000 ft at a speed of 120 ft/sec. The wing area is 500 ft^{2
}and the lift coefficient is 1.67. (You will need to use FoilSim
or your graph to find the density at the given altitude.)
10,581.12 lbs.
Step 11.
Calculate the lift coefficient for an aircraft with a 240 ft^{2
}wing area and a speed of 190ft/sec that can generate 9530 lbs of
lift in air with a density of 0.00165 slug/ft^{3}.
Solve equation for C1. C1 = 1.33
Step 12.
Find the velocity of an aircraft that generates 30,590 lbs of
lift when the wing area is 800 ft^{2}. The lift coefficient for
the aircraft is 1.4 and the air density is 0.00089 slug/ft^{3}.
Solve equation for V^{2} and take
the square root of the answer. V = 248 ft/sec.
Step 13.
Using the graph you constructed in Step 2, find the lift produced
by a wing area of 1200 ft^{2}.
Answers will vary.
Step 14.
Using your graph from Step 5 and FoilSim, find the altitude for
an aircraft that generates a lift of 15.39 lbs. (Remember: Set the airfoil
conditions to the original settings given at the beginning of this worksheet.)
Answers will vary.
