US Patent 9677659 Gearbox planet attenuation spring damper

An epicyclic gearing arrangement includes a planet gear rotatable on a planet bearing that is mounted via a support pin to a carrier of the epicyclic gearing arrangement. An attenuation spring is disposed between the outer surface of the bearing's outer ring and the opposing inner surface of the planet gear and includes an annular gap. A spring film damper is disposed between the cylindrical outer surface of the support pin and the opposing inner surface of the inner ring of the planet bearing and includes an annular gap. The support pin (96) and/or outer ring include oil feed holes that open into the respective annular gap(s). A gas turbine engine includes an epicyclic gearing arrangement having such a planet bearing.