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Pilot Test Draft Rev. 10/2012 – © Center for Educational Outreach, Baylor College of Medicine – Not for Release
2) Boomerang
Many Happy Returns
Time Needed
What It’s About
1 – 2 sessions
A boomerang is usually thought of as a wooden throwing
stick but boomerangs can be made of many different
materials including metals, plastics, and even paper. There
are two general kinds of boomerangs: returning kind and
non-returning. Both are ancient devices. The non-returning
boomerang goes back to the stone age and was used as a
throwing stick for hunting. It was shaped so that it could travel
long distances on a very straight flight path. Versions of the
non-returning boomerang were used in Europe, by some
western U.S Indian tribes, in Egypt, and in Australia.
Before You Start
Construct samples of the
different boomerangs your
students will be making.
Test fly them to make sure
you know the proper way
to throw (or flick) them and
have them return. The
paint stick boomerang
should be thrown outside
or in a large high-ceiling
room. Cut the sandpaper
sheets into quarters
You Need This Stuff
Per Group
• 4 copies of “Finger
Boomerangs” and “Four
Wing Boomerang” on
heavy paper/card stock
• copy of “Paint Stick
Boomerang”
• 8 paint sticks
• 20 heavy rubber bands
• 4 sheets sand paper (60
grit)
• colored marker pens
• scissors
• 4 safety goggles
The returning boomerang, raised to a high art by the
Australian Aborigines, was used for hunting and as battle
clubs, musical instruments and even fire-starters. For hunting,
the boomerangs would be thrown near roosting birds to
scare them into flight where they could be caught in nets.
They would also be thrown through a flock of flying birds in
hope of clipping a wing and bringing down dinner.
Both non and returning boomerangs are amazing
aeronautical devices. Boomerangs are rotating wings. They
are flat sticks with edges on the upper side curved like an air
foil. Non-returning boomerangs are straight
but the returning kind can have many shapes
and more than two “wings.” The classic
returning boomerang design is a lazy L shape
but they can also look like question marks.
Some are made with three or four wings (like
a cross). The shapes have to do with how
quickly the boomerangs return when thrown.
Large, open designs tend to travel the
farthest while tighter shapes or shapes with
extra wings tend to follow shorter paths.
The return of a boomerang is the result of several physical
processes - aerodynamic lift, gyroscopic precession, drag,
and gravity. When thrown properly, the boomerang is
oriented in a vertical plane. It is tossed slightly upward and
given a rapid spin. The spin produces a gyroscopic effect on
the boomerang to keep it spinning along the plane and not
flipping and fluttering. As the boomerang travels forward, it is
also spinning. The wings travel rapidly through the air and
these two motions produce a strong lift. Because the
boomerang is oriented vertically, the lift is sideways.
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Pilot Test Draft Rev. 10/2012 – © Center for Educational Outreach, Baylor College of Medicine – Not for Release
Think about a bicycle for a moment.
When riding, the spinning wheels
produce the gyroscopic effect that
keeps the bicycle upright and stable.
When turning the bike, the rider
merely leans to one side or to the
other. This puts a sideways force on
the spinning wheels. The wheels turn
in the direction of the rider’s lean. You
can see the same effect with a
spinning top. As the top slows, gravity
causes it to lean and this starts the
top wobbling in a circle. The effect is
called gyroscopic procession.
Back to the boomerang. As the
boomerang travels forward and spins,
it too experiences a sideways force.
The top wing of the boomerang spins
forward as the boomerang travels
through the air. The spin of the wing and the opposite air flow produce a strong lift to the side.
The lower wing, however, is going backward in the same direction of the air flow. The lower net
speed reduces the lift produced by the lower wing. The greater upper wing lift tries to tip the
boomerang over to the side. Rather than tipping over, the boomerang experiences gyroscopic
procession and turns in a wide circle. This creates the looping path in the air that brings the
boomerang back to the thrower.
What’s The Question
Will a boomerang always come back no matter how it is thrown?
What To Do
1. Ask students if they know what a boomerang is. What does it do? Have they ever thrown
one? Discuss the shape of airplane wings and compare those to the wings of boomerangs. Talk
about how airplane wings produce lift. Point out that boomerangs are rotating wings.
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Pilot Test Draft Rev. 10/2012 – © Center for Educational Outreach, Baylor College of Medicine – Not for Release
2. Have students create finger boomerangs out of card stock paper. Use the patterns on the
finger boomerangs page to make the boomerangs. Show how to launch these boomerangs
and have them fly their own. Are there other shapes that would return? Have them use the rest
of the card stock paper to try other shapes. Discuss which shapes work and which don’t. Ask
students speculate on why.
3. Graduate the students from small finger boomerangs to the larger four wing boomerang.
Show them how to throw this boomerang and have them fly theirs. Ask if they think there is a
limit to how big they could make this kind of boomerang. Would they have to use different
materials or add something to the boomerang to make it bigger? Discuss their ideas.
4. OPTIONAL: Move from paper to wooden boomerangs with paint sticks. It is very important
that students understand how to shape the wings. Refer to the diagram showing which edges
are rounded and which are sloped. Students should be careful not to mix up the edges. It will
help to mark the edges of the paint sticks sloped or rounded as a reminder during shaping.
Have students use sand paper to shape the stick edges, or school scissors can be used. When
all the edges are shaped, the boomerangs can be assembled with rubber bands. It may be
helpful to label the sides “sloped” or “rounded.” Take your students to a room with a high
ceiling (like a gym) or outside. It is best if the wind is not blowing. If there is a gentle breeze,
throw the boomerangs into the wind and not with the wind. The boomerang should be thrown
in the vertical plain, not horizontally. The shaped side of the boomerang should be to your left.
Use a chopping motion and spin the boomerang as it is released. The boomerang will follow a
counter clockwise direction.
(Here is one Internet source for wooden paint sticks:
http://www.jamestowndistributors.com/userportal/show_product.do?pid=2436
Note: The paint stick boomerang is a right-handed boomerang. If thrown with the left hand, the
shaped side should still be to the left. To make a left-handed boomerang, the rounded and
sloped edges on the pattern should be reversed. When throwing a left-handed boomerang,
the shaped side should be held to the right. It will circle in a clockwise direction.
Wrapping Up
• Hold a discussion on how boomerangs can be improved. What can be done to make them
stay in the air longer or travel out farther? What new materials can be used to make
boomerangs?
Extras
• Distribute colored markers and have students decorate their paint stick boomerangs.
• Advanced boomeranging: Teach students how to catch boomerangs. Do not try to catch
the boomerang by grabbing one of the wings. Your knuckles will get banged! Instead, wait
until the boomerang is about to drop the ground. It will still be spinning. Get under it and clap
your hands together, one hand above the boomerang and one below it.
• What would happen to the flight of the paint stick boomerang if it weighed more? Use hot
glue to glue a couple of pennies to the wing undersides. Be sure to keep the boomerang in
balance and place the pennies at the same point on each wing.
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Pilot Test Draft Rev. 10/2012 – © Center for Educational Outreach, Baylor College of Medicine – Not for Release
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Pilot Test Draft Rev. 10/2012 – © Center for Educational Outreach, Baylor College of Medicine – Not for Release
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