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How do counter rotating propellers on a helicopter increase the lift?
Wiki User
∙ 13y ago
Counter rotating blades on a helicopter are used to replace the traditional tail rotor found on most aircraft. Because the blades oppose each other (and therefore cancel out the torque created by the other blade) a tail rotor is not necessary. This allows all of the engine's power to be used for lift rather than powering the additional rotor.
Wiki User
∙ 13y ago
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For a helicopter to be stable as it flies it must have at least two propellers. why?
To counter the rotation induced by the lift rotor(s)
How does the helicopter stay stationary in the air?
Two things keep a helicopter flying, and another keeps it flying straight. To take off: 1) The blades are shaped like the wings of an airplane and create a difference in pressure (high underneath the wing, low above). This difference in pressure "pushes" the helicopter upwards (lift). But because of gravity, however, there might not be enough lift to take off from the ground. 2) In order to take off, the blades must rotate at supersonic speeds (to be stronger than gravity's push downwards), this make it possible to gain altitude. To "Fly:" 1) A helicopter's blades in air act like a boat's propeller in water. If the blades rotate at an angle, it will start moving. To make the helicopter hover, the blades must be perfectly straight up. At the same time, the rotating blades make the helicopter itself rotate the other way (about the axis of rotation). In a GPS, the helicopter would not be going anywhere like this (with no angle on the blades), but the Direction at which it is looking will be changing in circles 2) Helicopters need a way to fix this crazy-out-of-control spinning. They can use a tail rotor for this, but they can also use a "twin" set of blades that rotate in opposite directions (counter-rotating blades). With the addition of counter-spinning blades, now the GPS will be pointing at 1 direction. in summary: 1) By keeping the blades rotating fast enough to be lifting with the same force as gravity is pushing down, the altitude is kept the same. 2) By keeping the Blades from spinning at an angle, the Helicopter does not move to the sides. 3) By using a counter-rotating blades set, the helicopter is able to keep looking at one direction. with these 3 things, Helicopter are able to hover in air, and their GPS can be kept and a fixed height, at fixed position on a map, and at a fixed direction.
What direction does a helicopter's rotors spin?
Depending on the make of the helicopter, some will rotate clockwise and others will rotate counter-clockwise. However, the main rotor and tail rotor will spin opposite of each other. If the tail rotor spins clockwise, the main rotor will spin counter-clockwise. The main rotor also spins for lift, the tail rotor for control.
Why does a helicopter fly?
The rotor, shaped like an aeroplane wing, creates lift in the same way. The problem is in maintaining stability, as it will cause the body of the helicopter to rotate, too. That is why most helicopters have a tail rotor, to counter that effect and grant the pilot stability.
How do you tell if your ceiling fan is going clockwise or counter clockwise?
lay on the floor and look up at it. If it is moving the same direction as a clock it is moving clockwise. Hold a piece of tissue paper at a corner such that it is near (but not touching) the fan blades. If the fan lifts the paper toward the ceiling then it is rotating clockwise. This is best for winter. If the fan pushes the paper toward the floor (causing a breeze) then it is rotating counter clockwise. This is best for summer.
How counter propellors work?
Counter-propellers (proper name contra-rotating propellers) work by spinning in opposite directions. This cancels out torque in the same way as a helicopter uses rotors to cancel torque.
For a helicopter to be stable as it flies it must have at least two propellers. why?
To counter the rotation induced by the lift rotor(s)
Can you build a plane with normal propellers and with a helicopter rotor blade together and use it lift of the ground and then fly like a normal plane?
What you're talking about really isn't feasible. The closest thing you'll find to it is the V-22 Osprey, which uses counter-rotating propellers, and can only take off and land vertically.
What World War 2 single engine fighter had counter-rotating propellers?
The Lockheed P-38 Lighting had supercharged 12-cylinder Allison engines fitted with counter-rotating propellers to eliminate the effect of torque. These were left and right hand engines and maintenance was more difficult because a left engine could not be used in place of a right engine.
Can you give me a brief description about the helicopter?
helicopters fly and have big wirly things on their heads and look like birds The helicopter is an aircraft using rotary wings to give lift and a tail rotor or counter-rotating wings to give stability.
What aircraft have counter rotating propellers?
The POGO VTOL, the Tailsitter, the Convair XFY, and Lockheed XFV, to name a few. Ans 2 - All of those were experimental. -Popular working aircraft that used contra rotating props were the British Fairey Gannet, Westland Wyvern , Supermarine Seafire and Avro Shackleton.
What is a four engine aircraft prop rotation?
It all depends on the designer. Most propellers rotate clockwise, probably boiling down to history when props had to be started by hand and a right hand stance was the preferred method. However, technology has advanced, and many aircraft have contra rotating propellers like the P51, TU-95 and AN-70. While, counter rotating propellers, first used on twin engined airplanes, like the P-38, and the gigantic multi engined ME-323, are going to be available on the new A400M - as this reduces yaw - a common problem with "standard" multi prop planes.
Why did Cessna not make the 325hp engines on their 402c counter rotating?
not sure, counter rotating propeelers is extra weight and engineering complexity (more to fail) and costs more
How many propellers are on a propeller plane?
one prop per engine for most but there are a few planes with two counter rotating props per engine - the two props counter each others force (torque) to keep the props of powerful engines from spinning the plane number of blades on a prop can number 2, 3, 4, 5, 6 and 8 - the more blades the shorter each blade can be and the more power each prop can produceSingle-engine airplanes5 The most that I have seen if 5 blades. However, there was a single-set fighter-type plane that had counter-rotating propellers and it had 8 (?). This meant that 4 turned in one directin and 4 turned the opposite. This design would cancel out any torque that the propellers induced to the fuselage.Multi-engine airplanesNot sure but here are some suggestions.B-36 bomber had 6 engines with 3 blades each. It also was powered with 4 jet engines.The Hughes Flying Boat had 8 engines with 4 blades each: total of 32 propellers. Of course that aircraft was never operational; but it flew.
How does the helicopter stay stationary in the air?
Two things keep a helicopter flying, and another keeps it flying straight. To take off: 1) The blades are shaped like the wings of an airplane and create a difference in pressure (high underneath the wing, low above). This difference in pressure "pushes" the helicopter upwards (lift). But because of gravity, however, there might not be enough lift to take off from the ground. 2) In order to take off, the blades must rotate at supersonic speeds (to be stronger than gravity's push downwards), this make it possible to gain altitude. To "Fly:" 1) A helicopter's blades in air act like a boat's propeller in water. If the blades rotate at an angle, it will start moving. To make the helicopter hover, the blades must be perfectly straight up. At the same time, the rotating blades make the helicopter itself rotate the other way (about the axis of rotation). In a GPS, the helicopter would not be going anywhere like this (with no angle on the blades), but the Direction at which it is looking will be changing in circles 2) Helicopters need a way to fix this crazy-out-of-control spinning. They can use a tail rotor for this, but they can also use a "twin" set of blades that rotate in opposite directions (counter-rotating blades). With the addition of counter-spinning blades, now the GPS will be pointing at 1 direction. in summary: 1) By keeping the blades rotating fast enough to be lifting with the same force as gravity is pushing down, the altitude is kept the same. 2) By keeping the Blades from spinning at an angle, the Helicopter does not move to the sides. 3) By using a counter-rotating blades set, the helicopter is able to keep looking at one direction. with these 3 things, Helicopter are able to hover in air, and their GPS can be kept and a fixed height, at fixed position on a map, and at a fixed direction.
How many cranks did an Ariel square four have?
It has two counter rotating crankshafts
What is the second rotor on a helicopter for?
The small rotor on the tail is to counter-act the torque of the big rotor on top. So it is used for steering and to keep the helicopter stable.
