How do HELICOPTERS work? Coandă or Bernoulli ? Newton’s Laws – Airfoil Technology – Angle of Attack


in this video we will explain how a
helicopter flies through the flight made by the JAES CEO who will leave the
city of the Treviso to reach his field offices in Sicily. After getting on board
the JAES helicopter lifts from the ground and flies towards its destination.
As it leaves the city of Treviso it flies over the Sport Arena of Treviso basketball Team which recently achieved the promotion to the Serie A the top professional division of the Italian basketball championship this
important accomplishment was made possible thanks to the staff the
consortium members the players especially our team captain Matteo Imbrò
and thanks to the extraordinary fan club of Treviso Basketball Team (Fioi Dea Sud) During this flight we will see what are the main components and controls that allow
the helicopters to do the things airplanes cannot we will also see the
landing of the jeaious helicopter near the Mondello beach the Mondello beach is considered among the most beautiful and charming beaches of Sicily
the CEO of JAES was born in Palermo so he’s very attracted to this place and
he’s very happy to make his comeback here Helicopters are aircraft able to
stay still in the air and to move straight upwards or downwards their
ability to move freely in the air is guaranteed by large propellers turning
on vertical axes through power supplied by an engine it is believed that
Leonardo da Vinci sketches from the late 15th century were the predecessor to the
modern day helicopter but it was only during the 40s of the 20th century that
the world’s first practical helicopters made their appearance this helicopter
has a turbine engine called turbo shaft engine, this type of engine is not used to produce thrust but to power a mechanical
shaft it is in fact equipped with a compressor a combustion chamber and a
series of turbine stages inside the gas generator the purpose of the compressor
is to suck the air in and pressurize it the fuel burns in
first in this hot and pressurized air the exhaust gas produced by this
combustion leaves the combustion chamber passing through the turbines and makes
them turn there are two sets of turbines these turbines turn the compressor while
these turbines turned the rotor shaft the number of blades of the main rotor
can vary according to the size and weight of the helicopter what is certain
is that a helicopter can have a minimum of two up to a maximum of seven blades
as in the case of the Sikorsky s-64 one of the largest heaviest transport
helicopters in the Western world a rotor with many blades requires a larger and
powerful engine greater size means higher costs like in the case of wind
turbines a helicopter with many blades will be more powerful but less efficient
than one with less blades the blades of the helicopter by rotating in a certain
direction generate a equal force with opposite direction according to Newton’s
third law of motion for every action in fact there is an equal and opposite
reaction so if an object exerts a force on another object then that other object
is going to exert an opposite and equal force on the first object this means
that during their rotation the blades that are imparting a force to the air in
this direction they consequently receive an opposing force from the air this is
known as torque reaction which is opposed to the rotation of the blades so
if the blades start rotating in this direction the entire body and fuselage
of the helicopter would spin in the opposite direction for this reason every
helicopter has a tail rotor that allows to counteract this torque reaction the
tail rotor is composed of a single propeller placed precisely on the tail
of the helicopter by rotating this propeller pushes the air in the opposite
direction and produces thrust which is opposing the direction of the tour
reaction in order to stabilize the entire helicopter by changing the pitch
and consequentially the angle of attack of its blades this propeller is able to
increase or decrease the airflow passing through the blades and therefore
increase or decrease thrust opposing the torque reaction we already talked about
the angle of attack in our previous video about airplanes in which we
explained that this angle was formed between the chord line of the wing of
the plane and the airflow direction during the takeoff phase the tail force
tilted the plane increasing the angle of attack and consequentially the thrust
towards the wing this caused the whole aircraft to lift up the helicopter rotor
blades have a very similar airfoil technology compared to the airplane
wings and follow the same principle in a stable condition the thrust generated by
the tail rotor is able to perfectly balance the torque reaction of the main
rotor allowing the helicopter to stay still in the air with the nose facing in
this direction as we know in addition to taking off and landing vertically the
helicopter is able to perform many other maneuvers it can move forward and
backward and in general it can move in any direction in a 360 degree space when
it changes its direction it could also increase or decrease in altitude it is
also able to achieve a clockwise or a counterclockwise yaw rotation how does
it do that if we look closely at the main rotor of this helicopter we will
notice that it is composed of several elements like the shaft and the swash
plate mechanism the swash plate mechanism consists of a bottom swash
plate a bearing and a top swash plate which is attached to the rotor shaft the
bottom swash plate is able to perform these movements a bearing placed between
the bottom and the top swash plate ensures that the latter is able to
follow all the motion of the bottom swash
late while at the same time it can rotate along with the rotor shaft as the
collective pitch control is raised by the pilot which is the lever usually
located on the left side of his seat there is a simultaneous and equal
increase in pitch angle of all main rotor blades as it is lowered there is a
simultaneous and equal decrease in pitch angle the cyclic control is used to
control the main rotor in order to change the helicopters direction of
movement it is usually projected upward from the cockpit floor between the
pilots legs or between the two pilot seats in some models this is perhaps the
most sophisticated and delicate control of the entire helicopter since it
changes the mechanical pitch angle of each main rotor blade independently
depending on its position in the cycle the pitch is changed so that each blade
will have the same angle of attack as it passes the same point in the cycle
changing the lift generated by the blade at that point and causing each blade to
fly up or down in sequence as it passes the same point when the pilot moves the
cyclic forward the control rods will tilt the blades in this way increasing
the angle of attack only of the blades on the left side of the cycle by doing
this the lift will be greater on the rear side of the cycle causing the
helicopter to move forward it seems like a paradox actually this happens because
of gyroscopic precession this is a phenomenon occurring in rotating bodies
in which an applied force is manifested 90 degrees later in the direction of
rotation from where the force was applied as we’ve already seen to
counteract the torque reaction helicopters are equipped with the tail
rotor the anti-torque pedals located on the cabin floor by the pilots feet
control the pitch and therefore the thrust of the tail rotor blades this on
sequentially allows the pilot to control the direction that the nose of the
aircraft points from that neutral position applying the right pedal causes
the nose of the helicopter – you’re right and the tail – swing to
the left pressing on the left pedal has the opposite effect the nose of the
helicopter yaws to the left and the tail swings right during the flight the
helicopter pilot knows very well that for every action there’s a different
reaction so for instance moving the cyclic to the right the helicopter will
tilt to the right but at the same time it will lose altitude so it will be
necessary to control the collective and consequentially the anti torque pedal to
keep the helicopter at the desired height. After this long journey
the CEO of JAES finally arrives at his destination
now the helicopter pilot makes the necessary maneuvers to land on the
landing platform placed just a few steps from the beautiful Mondello beach 10
years in the industrial supplies sector have led JAES to become a qualified
partner for some of the most important helicopter manufacturers providing its
technical support over a wide range of industrial components necessary during
the production process of these incredible aircraft. We want to thank
Domenico Bonura a professional crew chief who supported us during the
creation of this video finally if you found this video useful let us know by
leaving a comment and subscribing to our YouTube channel to stay tuned on the
latest release of new videos Thanks for watching

26 thoughts on “How do HELICOPTERS work? Coandă or Bernoulli ? Newton’s Laws – Airfoil Technology – Angle of Attack

  1. I'm not sure I'm getting the cyclic control. Why the helicopter is moving forward when the blades are tilted on the left side of the cycle?

  2. Gyroscope precession means that a rotor behaves as a gyroscope, but a rotor is not a gyroscope..so can you explain that?

  3. Very cool but it does stop well short of explaining all the effects. For example, the anti-torque rotor having its center-of-thrust below the center-of-thrust of the main rotor causing a rolling moment on the airframe which must be offset by lateral cyclic and so on. The effect-counter effects of helicopter controls are almost endless.

  4. The turbine fins highlighted when describing which turn the compressor and which turn the shaft are incorrect.

  5. Please note :we had this comment we d like to share with all of you:
    I only made it to the turbine portion. You are missing the gearbox. The compressor section is only compressing air. At least in 250 series, of once the fire is lit, the first stage of the hot section turns the compressor section making the turbine self sustaining. The second set of turbine wheels drive the accessory gearbox and then on to the main transmission.

    The compressor section does not ultimately have an sort or mechanical linkage to the transmission drive system

  6. In another social we had this comment :Mi-26 has 8 mainrotor blades, so seven is not a maximum as stated as certain in the video ..

  7. Adding more blades does not automatically make a rotor head less efficient and more powerful. A Bell 212/412 is an excellent example of this. The rotating mass of the two bladed versus the four bladed system is approximately the same, so it takes approximately the same torque and consequently the same fuel burn for the same applied power. Its the characteristics of the blades themselves that change the helicopters flight performance. Without going into  excessive engineering detail, the two bladed version has better vertical lifting capability, especially at higher altitudes, while the four bladed system flies smoother and faster in forward flight.

  8. In another social we had this comment Mi-26 has 8 mainrotor blades, so seven is not a maximum as stated as certain in the video ..

  9. Very nice video congratulation.I usually dont watch all the video but this one I saw all. A couple nit-pick items: the blades on a helicopter are usually called rotors instead of propellers. I think, not all helicopters have tail rotors but I dont know if other can confirm. There are not systems and dual main rotor systems ( coax, tande, or intermeshing configurations).

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