SUMMARY: In
conclusion, a given airplane can fly because the lift generated by the
thrust, airfoil, and wingspan. To achieve this, the aircraft must
reach a certain velocity creating an airflow over
the airfoil. The velocity of the air over the airfoil determines when
the plane will leave the
ground or take off. When the plane reaches the
certain velocity, the pilot raises the angle of attack to an
appropriate value to safely leave the
ground and take flight. The bigger angle of attack
the better, until a certain point. When the angle of attack gets too
large, the air hits the top
(front) of the airfoil and "back eddies" and creates
a gap between the airstream hitting the wing and the airfoil. This
cause the plane to lose
altitude or go into what is called a stall.
There are
many unknowns that go along with aircrafts, but they can be figured out
if you break them into their four forces, and
calculate the Coefficient of Lift. All planes have
in common thrust, drag, weight and lift. They also all have a
Coefficient of lift. Planes
come in many different sizes and shapes and all have
unique aspects. Some planes need a great amound of take off speed and a
small
angle of attack and other planes need a small take
off speed and a large angle of attack. Some planes even are designed to
fly very
close to the ground and take advantage of the ground
effect. We have only examined two planes today and there are thousands
more
that have different needs and different capabilities. To me, the
fact that planes fly goes against the physics I have always known.
Newton had three laws that say "an object at rest
will stay at rest," "F = ma," and "for every action there is an equal
and opposite reaction." These
planes appear to be large objects that should
stay at rest, their force is their weight which points down so they
should stay put, and their force
downward acts eqully and opposite to the
ground pushung up. Some how, some way, hubdreds of thousands of
aircrafts are used to take off, fly and
land every day.