Is it a 'thing' that Airbus produce helicopter rotor systems that rotate differently?
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Is it a 'thing' that Airbus produce helicopter rotor systems that rotate differently?
Do Airbus build different rotor systems dependent on customer? I.e Clockwise for France, Counter-clockwise for Germany? I heard this today, never heard it before...
skadi
You don’t honestly believe that they would design different versions of the same model for customers?
Below the Glidepath - not correcting
I thought it was because Coriolis forces provide an additional rotational component to clockwise rotating systems in the northern hemisphere and vice versa. That's why helicopters aren't allowed to cross the equator without some nautical engineering ceremony performed by drunken sailors...perhaps I'm getting confused.
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nautical engineering ceremony performed by drunken sailors...perhaps I'm getting confused.
Frighteningly half those blokes were dressed as women and looked better than some of the Pompi lasses!
The SA321 Super Frelon was the exception with a 6 bladed Sikorsky S61 derived Main Rotor system rotating counter-clockwise. Should have done the same thing for the S61, that would be a great lifter!
Rotors turn a different way for the same reasons that propellers vary their rotation. It all depends where the drive is taken off the engine.
All engines rotate clockwise looking from the front. If one attaches the propeller on to the crankshaft at the front of the engine the propeller will rotate clockwise looking from the front. In the USA the propeller drive is normally taken off the back of the engine where a clutch would be in an automobile so they turn the engine around so the propeller is in front therefore the propeller goes anti clockwise looking from the front.
Helicopter drives to the gearboxes using a similar speed reduction system will cause the rotors to go different ways according to the design of the piston engine. With gas turbines you arrange it so that it goes the same way as before.
An example is the Super Frelon. French designed and built but the only one with an anti clockwise rotation because the rotor system was licence built from Sikorsky.
All engines rotate clockwise looking from the front. If one attaches the propeller on to the crankshaft at the front of the engine the propeller will rotate clockwise looking from the front. In the USA the propeller drive is normally taken off the back of the engine where a clutch would be in an automobile so they turn the engine around so the propeller is in front therefore the propeller goes anti clockwise looking from the front.
Helicopter drives to the gearboxes using a similar speed reduction system will cause the rotors to go different ways according to the design of the piston engine. With gas turbines you arrange it so that it goes the same way as before.
An example is the Super Frelon. French designed and built but the only one with an anti clockwise rotation because the rotor system was licence built from Sikorsky.
Avoid imitations
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Good theory, but unfortunately it’s not true that all aero engines rotate in the same direction.
Rotors turn a different way for the same reasons that propellers vary their rotation. It all depends where the drive is taken off the engine.
All engines rotate clockwise looking from the front. If one attaches the propeller on to the crankshaft at the front of the engine the propeller will rotate clockwise looking from the front. In the USA the propeller drive is normally taken off the back of the engine where a clutch would be in an automobile so they turn the engine around so the propeller is in front therefore the propeller goes anti clockwise looking from the front.
Helicopter drives to the gearboxes using a similar speed reduction system will cause the rotors to go different ways according to the design of the piston engine. With gas turbines you arrange it so that it goes the same way as before.
An example is the Super Frelon. French designed and built but the only one with an anti clockwise rotation because the rotor system was licence built from Sikorsky.
All engines rotate clockwise looking from the front. If one attaches the propeller on to the crankshaft at the front of the engine the propeller will rotate clockwise looking from the front. In the USA the propeller drive is normally taken off the back of the engine where a clutch would be in an automobile so they turn the engine around so the propeller is in front therefore the propeller goes anti clockwise looking from the front.
Helicopter drives to the gearboxes using a similar speed reduction system will cause the rotors to go different ways according to the design of the piston engine. With gas turbines you arrange it so that it goes the same way as before.
An example is the Super Frelon. French designed and built but the only one with an anti clockwise rotation because the rotor system was licence built from Sikorsky.
Just make sure the t/r blades are fitted correctly for the rotation.......
Sycamore - did you witness the TH incident as well? Amazing that it took so long to realise it was a possibility!
Sycamore - did you witness the TH incident as well? Amazing that it took so long to realise it was a possibility!
Really? I seem to recall Stanley Hooker mentioning in his book that Merlin and Griffon crankshafts rotate in different directions. And I'm sure I've hand-swung direct-drive light-aircraft propellers in different directions in my time.
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I believe the P-38 Lightning had "handed" Allison engines, left hand engine crankshaft rotating clockwise, right hand anti-clockwise. Some Twin Comanches and Navajos had counter-rotating props which I think also used handed engines rather than gears to determine prop rotation.
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I talked to a Sikorsky rep once about why they did not upgrade the S61 with more powerful engines, and composite rotor blades. He said that Sikorsky were quite willing to do it, but they wanted the operators to put up some money first.
No one would.
No one would.