HIGH THRUST GEARED GAS TURBINE ENGINE

摘要

A ratio of an outer diameter of a fan hub at a leading edge of the blades to an outer tip diameter of the blades at the leading edge is greater than or equal to about 0.24 and less than or equal to about 0.38. The fan tip diameter is greater than or equal to about 84 inches (213.36 centimeters) and a fan tip speed is less than or equal to about 1050 ft / second (320.04 meters / second). A bypass ratio, a gear ratio and an AN2 value are also claimed. The fan drive turbine has between three and six stages.