Abstract: A gas turbine engine turbine assembly includes a high pressure spool having a high pressure turbine drivingly connected to a high pressure compressor by a high pressure shaft which is rotatable about an engine centerline. A low pressure turbine has counter rotatable low pressure inner and outer shaft turbines with a row of low pressure variable vanes disposed therebetween and drivingly connected to coaxial low pressure inner and outer shafts respectively which are located radially inwardly of the high pressure spool. The low pressure inner and outer shaft turbines are drivingly connected to a forward and aft fan blade rows by the low pressure inner and outer shafts. A single direction of rotation booster is drivenly connected to the low pressure outer shaft and axially located aft and downstream of the aft fan blade row.

Abstract: An aircraft gas turbine engine includes a low pressure turbine having a low pressure turbine flowpath and low pressure inner and outer shaft turbines with counter rotatable low pressure inner and outer shaft turbine rotors, respectively. The low pressure inner and outer shaft turbine rotors include low pressure first and second turbine blade rows disposed across the turbine flowpath which are drivingly connected to first and second fan blade rows by low pressure inner and outer shafts, respectively. At least one row of low pressure variable vanes is operably disposed across the low pressure turbine flowpath between the low pressure inner and outer shaft turbines. The low pressure first turbine blade rows of the low pressure inner shaft turbine may be in tandem with or interdigitated with the second turbine blade rows of the low pressure outer shaft turbines.