Patent attributes
An engine for an aircraft includes an engine core including a turbine, a compressor, and a core shaft connecting the turbine to the compressor; a fan located upstream of the engine core, the fan comprising a plurality of fan blades; and a gearbox. The gearbox receives an input from a gearbox input shaft portion of the core shaft and outputs drive to the fan so as to drive the fan at a lower rotational speed than the core shaft. The gearbox is an epicyclic gearbox including a sun gear, a plurality of planet gears, a ring gear, and a planet carrier on which the planet gears are mounted. The carrier and the gearbox input shaft each have a torsional stiffness, and a carrier to gearbox input shaft torsional stiffness ratio is greater than or equal to 70.
