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The Fly Higher Tutorial III
Helicopters
Where are the wings?
Eurocopter EC135
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First:
Some History
Leonardo da Vinci designed the first ‘helicopter style’ aircraft which
he called the ‘Helical air screw’.
Though drawn with instructions on how it would operate it was never
made or tested at the time. Modern day physics suggests this would
not fly.
You should
have heard of
Leonardo da
Vinci! What
else is he
most famous
for?
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Leonardo da Vinci
Some History
Was not only a pre-eminent scientist and engineer in his
time (late 15th Century) but also….
A fantastic artist, best known
for painting ‘Mona Lisa
and the mural ‘The Last Supper’
And a pioneering student of human anatomy,
illustrated by this famous diagram: ‘The Viruvian Man’
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First Working Helicopters
Some History
In 1906, two French brothers, LouisCharles and Jacques Bréguet, began
experimenting with wing shapes for
helicopters; in 1907 they successfully
demonstrated the potential for
rotary-winged flight with Gyroplane
No 1.
It took 40 years more for man to
perfect the design of the
helicopter. In 1944, Igor Sikorsky, a
Russian born American, flew the
first mass produced Helicopter, the
Sikorsky R-4.
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First Working Helicopters
Some History
Early take off of a Sikorsky R-4b helicopter.
Please watch video 1
take off of a Sikorsky R-4b helicopter
Source YouTube HeloSociety
Edition Fly Higher
Source Youtube HeloSociety
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Today´s Helicopters
Today’s helicopters come in many different sizes and can fulfil a variety of
roles. They also vary in how they operate and work when in flight.
Boeing CH-47 “Chinook”
Sikorsky CH-124 “Sea King”
Robinson R22
In your groups try to think of as
many different roles for helicopters
as you can, and why they are
preferable to aeroplanes in each
case you describe.
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Parts of a Helicopter
As a class or in groups can
you work out what are
each of these parts of the
Helicopter?
8
6
11
7
9
Can you get all 11?
On your table you have the 10
diagram and a list of the names
of the technical parts to help.
1
4
5 2
3
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Parts of a Helicopter
Hopefully you matched the technical names to the diagram as follows:
ANSWERS: Pt1
The Cabin
1) Fuselage. Just like on a
plane we need a main
body to house the
people
and
attach
everything else onto.
2) Landing Skids. These replace the wheels on an aeroplane. Can you explain
why a helicopter does not need wheels?
3) Cabin doors. Needed to get people in and out of the aircraft. Helicopters
don’t fly as high as commercial airplanes so the doors are generally much
lighter than the doors on an aeroplane. Again, can you explain why this
would be?
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Parts of a Helicopter
ANSWERS: Pt2
Tail Section
4) Tail boom. This forms part of the
overall structure and encases
various parts of the tail section.
5) Elevator. This is controlled by the
pilot and allows the Helicopter to
pitch up and down.
6) Tail fin. Allows the Helicopter to
yaw left and right.
7) Tail rotor. This component pushes
the helicopter in the opposing
way to the main rotor; Otherwise
(as a reaction to the rotor) the
helicopter would just spin around
and around!
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Parts of a Helicopter
8) Rotor. Shaped like aeroplane wings,
these spin around to generate the
required lift for the aircraft.
ANSWERS: Pt3
Powerplant & Main Rotor
9) Engine. This powers the helicopter
and comes in varying types and sizes.
10) Transmission. This part converts the
horizontal turning motion of the
engine into a vertical motion which
spins the main rotors.
11) Swash Plate. A complex arrangement
of connections which tilt the blades
at varying angles to allow the
helicopter to move in all directions.
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Rotor blades:
How do we get into the air?
As we have seen previously, the Rotor blades spin around and looked to be
shaped like wings, but how does this get a helicopter into the air?
Above is an end-view drawing and a picture of a rotor blade.
As you can see, these show that the blade is shaped like an
aerofoil or aeroplane wing. An aerofoil generates lift by the
means of a pressure difference, exactly as it does on an
aeroplane.
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Rotor blades:
How do we get into the air?
Air
Each rotor blade has it’s top surface curved.
We get a large amount of air to flow over the blades by spinning them.
The air is forced to flow much faster over the rotor blade than under it.
This causes a lower pressure on the top than on the bottom.
This pressure difference results in a force LIFT, which pulls the helicopter upwards.
The helicopter is effectively ‘sucked’ into the air as it takes–off!
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Rotor blades, there´s more!
How do we get into the air?
Now we know how our ‘LIFT’ is generated, getting us into the air, we
must now be able to move around.
If we don’t move our blades in any direction but simply leave them
spinning we would just continue going straight up!
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Moving in the Air
But we also want to move left or
right, and ‘tilt’ in a certain direction.
How do we do that?
Blades
The Hub
Swash
Plate
Metal Rods [that move up and
down tilting the hub and blades]
This is where a part of the Helicopter
called the Swash Plate comes in.
This comprises of a series of metal
rods which are located where all the
blades of the rotor are connected
together, the Hub.
This Swash Plate tilts the blades by
pushing or pulling at certain points,
so altering the pitch (angle) of the
blades individually as they revolve
around in the air.
Simple… Huh?
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Rotor blades: there´s still more!
If we want to move backwards
then we tilt our hub and blades up
and we shall move up… and BACKWARDS
backwards.
If we want to do the opposite and
move forward, we tilt our hub and
blades forward and give ourselves
forward motion.
If we want to move sideways we
would tilt our hub and blades left
or right.
FORWARDS
LEFT
OR
RIGHT
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How a helicopter is controlled
Knowing that the rotor blades
will tilt to move the helicopter in
various directions, how does the
pilot control them?
COLLECTIVE
This is where the Helicopters
three main controls come in:
CYCLIC
• The Cyclic
• The Collective
PEDALS
• Pedals
Pilot’s Chair
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How a helicopter is controlled:
The Cyclic
The cyclic is shaped like a oldfashioned hand brake in a car
and controls the Swash plate we
looked at earlier.
With this ‘control stick’ in one
hand the pilot controls the tilt
angle of the Swash plate and
therefore can decide in what
direction the Helicopter flies.
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How a helicopter is controlled:
The Collective
This is shaped like a joystick
from an old computer and looks
a lot like the control stick
airplane pilots use.
With this ‘Collective’ controller
in their left hand the pilot can
determine
whether
the
helicopter climbs or descends.
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How a helicopter is controlled:
The Pedals
Lastly there are two pedals where the pilot
must place each foot.
With these, the pilot can move the tail
rotor sideways so turning the aircraft left
or right whilst keeping the fuselage level.
With a skilled combination
of these three controls the
pilot can take the Helicopter
almost anywhere!
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Helicopters
You should now know more than
enough to follow this film about
helicopters.
Please watch video 2
Helicopters for beginners
Source YouTube CrazyHeliDude
Edition Fly Higher
Source Youtube CrazyHeliDude
Interested?
When you get home have
a look at “Helicopters for
beginners” on YouTube.
There is some fascinating
stuff there!
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Consortium
Follow us on
www.flyhigher.eu
/groups/Fly-Higher-Project-4737756
/flyhigherproject
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For further information flyhigher@inovamais.pt
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