Ball Bearings vs. Liquid Bearings in aeroplanes

[z-matrix]

Bearings (http://www2.et.lut.fi/lvt/en/rese/bear.htm)
Google - Bearings (http://www.google.com/search?hl=en&q=liquid+bearings)

SKF magnetic Bearings (http://www.skf.com/portal/skf_rev/home)
Magnetic Bearings - Google (http://www.google.com/search?q=magnetic+bearings)

i was wondering if i get a liquid bearing from somewhere like a dead liquid bearing hdd, and put it in to a cd-rom motor, it whould fly more silently, and hopefully more.
Another alternative whould be Magnetic Bearings, but i guess this whould be much more expensive... and heavier.
what do you think?

[Pete P]

I believe liquid bearing use oil in a sealed environment....
Could be wrong :-P

[Comatose]

To what end? At RC plane speeds (couple thousand rpmish) ball bearings are as silent as you could possibly want. The noise is coming from the prop, mostly. Having a PWM switching frequency in the audible range doesn't help, either.

[z-matrix]

i think it whould be especially useful in jets, with very high rpm,

but liquid bearings should have much longer lifetime, easier to spin, than ball bearings, so higher efficiency could be possible, i'm sure some noise is coming from the ball bearings, i tried to spin a hdd motor, and there is the ball bearing sound.