Page 19 - August2017

THRUST – The forces produced by some kind of
Propulsion ( ENGINE ) which pushes air backward from
the aircraft causing a reaction that makes the aircraft
move forward.

“What Makes An AIrplane Fly?”

Several hundred years ago a young man by the name of
Isaac Newton was sitting under an apple tree when
suddenly he was struck on the head by something hard that
fell from the tree he was sitting under. Isaac looked around
and was surprised to see a large red apple lying on the
ground by his side. DRAG – The opposite reaction to the force of THRUST
causing a resistance to the forward motion of the aircraft

LIFT – Is an upward force applied in such a way that
He picked up the apple and at the same time a large bird
that was hunting for food on the ground just in front of him allows a heavier than air body (airplane) to overcome its
started to flap its wings vigorously and began to climb own weight due to the forces of GRAVITY
skyward above the tree that Isaac was sitting under. Isaac
was very puzzled by this and like us today asked the all-
important question…

“WHY DOES IT DO WHAT IT DO AND WHAT MAKES IT DO
WHAT IT DOES “?

Little did Sir Isaac Newton know at the time that he had just
discovered two of the things that today make up what we
now call the LAWS OF PHYISICS .
WEIGHT – Is the force caused by the size of the airplanes
“Great story Teach but what has that got to do with how body being acted upon by the force of GRAVITY in a
airplanes fly “? downward direction. It is also the opposite of the force

“Be patient my young Cadet and I will tell you - It all begins known as LIFT
with four forces “

THE FOUR FORCES OF FLIGHT