Epicyclic gear system having two arrays of pinions mounted on flexpins with compensation for carrier distortion

An epicyclic gear system (A) includes sun and ring gears (2, 4) and planet pinions (6, 8) arranged in two side-by-side arrays (a, b) between the sun and ring gears, there also being a carrier (10, 50) to which planet pinions are coupled through flexpins (30). The carrier has primary and secondary walls (20, 22) between which the pinions are located and webs (24) connecting the walls. The flexpins for one array of pinions are cantilevered from the primary wall and the flexpins for the other array of pinions are cantilevered from the secondary wall. When the gear system operates, the carrier along its primary wall is subjected to an externally applied torque which transfers through the system at the planet pinions of the two arrays. The load path (pa) for the pinions at the primary wall is shorter than the load path (pb) for the pinions at the secondary wall, and this disparity causes the carrier to distort. To compensate for this distortion so that the pinions of the two arrays will mesh more evenly with the s