Airplanes are an efficient way of traveling to far places. Airplanes

are
amazing if you know what and how the air keeps the plane airborne. There
are

three components of flight: aerodynamics, the Bernoulli principal and
supersonic

flight. Some other things about flight are the four forces, lift,
drag, weight,

and thrust. One of the basic things you need to know about
airplanes is that the

places where the plane can balance on one point called
the center of gravity.

The tail on the plane is needed to balance the
pitching movement. First of all,

aerodynamics plays a major role on many
things, especially in airplanes.

Aerodynamics is the reaction of the air
on the specially shaped wing that lifts

an airplane off the ground. Also,
aerodynamics is the study of gases in motion.

The term aerodynamics comes
from the Greeks meaning air power. Isaac Newton

bases aerodynamics on the
physics theorem. People who experiment with

aerodynamics are called
aerodynamicist. Their basic tool is the wind tunnel. A

professor of
engineering, Osborne Reynolds, conducted many experiments with

paper
airplanes and regular airplanes and found out Viscosity (thickness)

affects
the way fluids behave. All fluids have some viscosity. As a fluid flows

over
a surface, the fluid molecules closest to the surface cling
microscopic

roughness of the surface. As you move away from the surface,
there is a small

transition distance where the fluid’s viscosity limits the
change in speed of

the adjacent molecules, until at a certain distances the
fluid is at full speed.

(Paper airplane aerodynamics
www.geocities.com/capecanaveral/1817/paene/html)

Osborne invented a
number that was devised which gives the importance of

viscosity in fluid
flow. It’s called the Reynold’s number. Reynold’s

number =9340 for air so
you’d take 9340x velocity relative to surface (mph) x

length over surface
fluid has traveled feet. This determines how influential the

viscosity is.
Secondly, Swiss mathematician and physicist, Daniel Bernoulli,

created
Bernoulli’s principle in 1738. It stated the concept that as the speed

of a
moving fluid increases, the pressure within the fluid decreases. An

increase
in the fluid’s speed must be matched by a decrease in pressure.
The

mathematical theorem for the Bernoulli affect is p + ? p V2. One source
said,

"the principle also applies to the spinning of a baseball" (Simons,
1989,

pg. 23) The rotation causes an additional velocity component to be sent
in the

direction of rotation. Because of all that, the total velocity around
the ball

is higher on one side then the other. This is an example of how
Bernoulli’s

principle works. Next, supersonic flight includes speeds from
mach one to five:

above five are considered hypersonic. The bell X-1 rocket
plane first achieved

supersonic flight in 1947. "Many attempts had been made
before that but when

the plane ran against the sound barrier the pilot often
lost control when the

shock waves built up against the surface" (Compton’s
1994). Mach one is

considered traveling below the speed of sound (subsonic).
Mach two is traveling

twice the speed of sound (supersonic). All aircraft’s
that are traveling at

supersonic or hypersonic speed create a shock wave that
represents a big change

in the air pressure. The shock is in reality a cone
shape (a mach cone). The

mach cone at mach 1 is more of a hill but as the
mach numbers increase, the cone

gets pushed back to more of a mountain. As
the wave gets closer to the wing, the

drag increases dramatically. When you
are at subsonic mach numbers, the drag is

increased as a result of small wing
span or low aspect ratio. "Low aspect

ratio is the ratio of span to mean
chord of an airfoil" (Reithmaier, 1995). A

typical supersonic airplane gives
off two main shock waves: bow shock and tail

shock. Next, there are four
forces of flight; lift, weight, drag, and thrust.

Drag is the air
resistance to forward motion. Thrust is produced by the power

plant that
contracts drag. The formula for drag is D=1/2 x p x V2 x S x CD. The

S in
this formula is the area of the wing area of the whole aircraft. If the

plane
is level, lift will equal weight. In conclusion, airplanes have a lot
of

scientific information behind the way that the plane stays in the air.
The

airplanes have to be aerodynamically shaped to reach supersonic flight.
The

Bernoulli affect also helps keep the plane in the air by measuring
the viscosity

and comparing it to the air pressure. Supersonic flight is from
mach 1 to mach 5

and above that is hypersonic. This relates to my experiment
in many ways. The

paper airplane has to be aerodynamically shaped so it can
fly well. The paper

airplane also has a Reynolds number, which was created by
Daniel Bernoulli. The

equation for paper airplane is 9340*10*.4 =37,000. Of
course the project

airplane will not be traveling at supersonic speeds but it
would have the same

concept of cutting through the air.