Patent ID: 8205432

Claim:
A two-stage turbofan system for use in a gas turbine engine through which inlet air travels from an upstream direction to a downstream direction, the two-stage turbofan system comprising: a second-stage fan shaft for connection with a drive shaft in the gas turbine engine such that the second-stage fan shaft is driven at a speed of the drive shaft; a stationary torque tube having a fixed upstream portion for connection with a fan case in the gas turbine engine; a gear system comprising: a ring gear connected to the second-stage fan shaft; a stationary sun gear connected to a downstream portion of the torque tube concentric with the ring gear; and a gear carrier positioned concentrically between the ring gear and the sun gear, the gear carrier having a plurality of planet gears positioned in the gear carrier to interface with the sun gear and the ring gear; and a first-stage fan shaft having a downstream portion extending from the gear carrier such that the first-stage fan shaft is driven at a speed reduced from that of the drive shaft.