Question on using spherical bearings as blade pitch bearing?Hey Chuck, could you ring in?

[skyguynca]

I used to work on helicopters in the Army and I was always amazed that Bell used spherical bearings on the tail rotor blades. We used to change them out all the time by staking in new ones when the old ones acquired too much play.

Why can't you use spherical bearings for the main rotor blades too? I did some math calculating the blade is composite and weighs 10 lbs would exert 23636 lbf at 410 rpms with a tip speed of 408 fps.

I calculated that you would need a bearing that has atleast 10 degrees of angular pitch and have a rating of atleast a static radial rating of 20,000 lbf and a dynamic rating 14,000 lbf and a thrust rating of 3500 lbf.

I found one that uses a 1 in bolt and the housing is .75 in thick and 1.4374 in diameter. That would work nicely on a 1 in thick by 5 in wide teetering hub bar.
It is permanently lubricated with dry lubricant. Has a recommended Load limit: Static Radial 21,787lbf - Static Thrust 3,663 lbf - Dynamic Radial 14,524

I think it would make a two blade helicopter head very simple.

Is there any reason this work not work?

David M.