Aircraft gas turbine engine with control vanes for counter rotating low pressure turbines

An aircraft gas turbine engine includes a low pressure turbine (26) having a low pressure turbine flowpath and counter rotatable low pressure inner and outer shaft rotors (200, 202) having inner and outer shafts (130, 140), respectively. The low pressure inner and outer shaft rotors (200, 202) include low pressure first and second turbine blade rows (138, 148) disposed across the turbine flowpath and drivingly connected to first and second fan blade rows by low pressure inner and outer shafts (130, 140), respectively. At least one of the low pressure first and second turbine blade rows (138, 148) is interdigitated with an adjacent pair of one of the turbine blade rows (138, 148). At least one row of non-rotatable low pressure vanes (210) is disposed across the low pressure turbine flowpath between a non interdigitated adjacent pair (218) of one of the turbine blade rows (138, 148).