2. Drag Drag is one of the four forces of flight. Drag is a force
of flight that slows down your acceleration. When
there is too much drag, objects will not succeed in
flying.
Planes use drag for landing.
Too much drag slows a
plane down.
Drag is the opposite of thrust.
Imagine you are cruising around in car. Then, you
hold on to a piece of paper and you stick your hand
out the window. The force pushing against your hand
is drag.
3. Thrust
Thrust is another force of flight. Thrust
is the force of flight that helps flying
objects speed up.
Thrust is the opposite of drag.
4. When you pull back
a toy car
(for some toy cars)
It starts up its
“engine” and that
creates thrust.
5. Lift
Lift is another force of
flight that lifts a plane
up.
Lift is the opposite of weight/gravity.
When a plane goes up,
there is more lift than
weight.
When planes are
ready to take off,
there needs to be
more lift than
gravity.
When a plane is
level in the air,
there is lift and
weight.
The shape of a plane wings (airfoil)
helps a plane with lift. The top of the
wing is curved. The bottom of the
wing is flat. The top of the wing has
low air pressure. The bottom has high
air pressure.
6. Imagine you are on a plane ready to take off. To take off, the
plane needs lift. Lift is caused by the air pressure on the wings.
There needs to be more lift than weight to take of. Wind speeds
and thrust help lift to be able to fly. For example, if the wind is
blowing at 15 knots, there is more lift than weight, and there is
more thrust than drag, a plane will be able to take off
successfully.
7. Weight/Gravity
Weight is another force
of flight that pulls down
a flying object. Gravity is a force
that keeps things
from drifting away.
The heavier an
object is, the
stronger its pull is
on Earth.
The heavier a plane is, the
more lift, and therefore
more use of thrust, is
required to make the
plane fly.
The lighter a plane is,
the less weight there
is. Therefore, is would
use less thrust, so the
plane wouldn’t use as
much fuel.
When you drop an egg from
a high place, the force
pulling it toward the ground
is gravity.
