
Beginner's Guide
to Aerodynamics
Drag Equation  Level 2
Activity
In
Drag Equation Level 1, our pilot flew his first aircraft
of the day. If you have not already done so, you may want to go to this
activity first to prepare you for the second flight. You
may also want to review The
Drag Equation tutorial before trying
to complete these questions.
 Since the type
of aircraft has changed so has it's wing area. Once again, in order
to work with our drag equation, we first need to find it's wing area.
Hint: Find the areas of each common figure and obtain their
sum. (Note: You may assume the 2 right triangles are congruent.)
 The drag coefficient
for our second aircraft was calculated at .365. When the pilot reached
the desired cruise speed of 400 mph, the air density was .00052 slugs/cu.
ft. What was the aircraft's thrust? Hint: You should note from
the units table in Drag Equation
Level 1, you must first convert the area to the proper units.
(Note: 1 inch = 2.54cm.)
 Step 1:
Convert area to proper units.
Step 2:
Determine the thrust of the aircraft.
 The thrust
of the first aircraft the pilot flew (Drag
Equation Level 1) under these same conditions is 150,000
pounds. If the 2 aircrafts weigh the same, which plane is more efficient?
 If you enjoy finding
the wing areas and would like to determine approximate wing areas for
actual aircraft using models, go to Model
Wing Areas.
