Epicyclical gear systems are typically equipped with straddle--mounted planetary idlers and are supported by
pins on the input and output sides of a carrier. These carriers can be either one--piece or two--piece carrier
designs. Traditionally many of the higher power rated epicyclic gear systems use cylindrical roller bearings to
support the planetary gears. This paper will demonstrate that using a preloaded taper roller bearing in an
integrated package should be the preferred choice for this application to increase the bearing capacity, power
density, and fatigue life performance. Based on DIN281--4 calculations, this patented [1], fully integrated
solution allows for calculated bearing fatigue lives to be 5 times greater than a non--integrated solution and
more than 1.5 times greater than a semi--integrated solution, without changing the planet gear envelope.