As the rotor turns.

All_In

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Jean Claude

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Bad example , John. Because it is a bolkov 105 rotor, with 4 blades without drag hinge or flapping hinge (Doman's rotor?)
 

XXavier

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Bad example , John. Because it is a bolkov 105 rotor, with 4 blades without drag hinge or flapping hinge (Doman's rotor?)
No... The Doman rotor is a floating-hub rotor. It's also hingeless, but there's a difference. The Doman rotor aligns itself so that the axis perpendicular to the tip-path plane is always parallel to the rotor axle, that rests on a spherical bearing. In the hingeless rotor of the BO-105, the axis perpendicular to the tip path is not parallel to the rotor axle, so the blowback is achieved by blade-root flexing, and not with a physical hinge...
 

C. Beaty

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If the CG of the rotorcraft was not offset from rotor center, there would never be need of flap/drag hinges.

The BO-105 minimizes offset by locating the heavy stuff; – Engines and gearboxes above the cabin roof.
 

Jean Claude

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You're right, the Bolkov rotor is not Doman's systèm He is rigid. Flapping and lead lag are entrusted to the only flexibility of the blades.
Even without offset of the CG, there remains the flapping due to the flight forward ie about 2 degrees
 

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I found the movement different and wondered why. You guys Rock!
 
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