the prior arrangement differs in that the bearings 67 are formed by smaller diameter versions of the separate hubs 56 of the improvement on the outer diameter 68 of which a high load bearing material 70 such as silver has been plated or otherwise deposited the bearings 67 include oil passages 60 and recesses 62 and like the hubs 56 are non rotatable as a consequence all the bearing loads are carried by the radially inward portions of the bearing surface which thus receive all the wear in addition the planet gears 71 of the prior arrangement have inner diameters rotatably carried on the bearings 67 which are about one quarter smaller than the inner bearing diameters of the improved version thus the gears 71 are substantially heavier than those of the improved version in operation of the improved version of fig1 3 oil delivered through the passages and grooves 50 51 52 54 to the recesses 55 of the axles flows outward through passages 60 to the recesses 62 of the hubs 56 from which it is carried between the bearing and hub surfaces during rotation of the planet gears 34 the planet carrier 32 rotates whenever the rotor 14 is in motion and causes the planet gears to orbit as well as rotate at relatively high rotational speeds the masses of the planet gears thus develop significant centrifugal forces which act.