Geared turbine engine with relatively lightweight propulsor module

A gas turbine engine comprising:

• a propulsor assembly consisting of a fan and a fan drive turbine, the fan including a hub and an array of fan blades extending from the hub;
• a nacelle circumscribing the fan, wherein the propulsor assembly excludes the nacelle;
• a bypass ratio of greater than 10;
• a low fan pressure ratio of less than 1.45 at cruise at 0.8 Mach and 35,000 feet, the fan pressure ratio measured across the fan blades alone;
• an epicyclic gear train defining a gear reduction ratio of greater than 2.3;
• wherein a weight of the propulsor assembly is less than 40 percent of a total weight of the gas turbine engine, excluding the nacelle;
• a high spool including an outer shaft connecting a high pressure turbine and a high pressure compressor, the high pressure compressor including a plurality of stages;
• a low spool including an inner shaft concentric with the outer shaft, the inner shaft connecting a low pressure compressor and the fan drive turbine, the inner shaft driving the fan through the gear train to drive the fan at a lower speed than the low speed spool, and the low pressure compressor including a plurality of stages;
• wherein the high pressure turbine is a two-stage turbine, the fan drive turbine includes three turbine rotors but fewer than six turbine rotors, and a weight of the fan is greater than a weight of the fan drive turbine;
• wherein the fan drive turbine includes an inlet, an outlet, and a pressure ratio greater than 5:1, wherein the pressure ratio is a ratio of a pressure measured prior to the inlet as related to a pressure at the outlet prior to any exhaust nozzle;
• and
• wherein the fan comprises no more than 20 fan blades that fit within an annular fan case that surrounds the fan blades to define a bypass duct, and a ratio between a total number of the fan blades and a total number of the turbine rotors of the fan drive turbine is between 3.3 and 8.6.