A gas turbine engine includes a fan section that includes a fan with fan blades. The fan section drives air along a bypass flow path in a bypass duct. A gear reduction is in driving engagement with the fan and has a gear reduction ratio of greater than 3.0 and less than 4.0. A low spool includes a low pressure turbine that drives a low pressure compressor and drives the gear reduction to drive the fan at a speed slower than the low pressure turbine. The low pressure compressor includes a greater number of stages than the low pressure turbine. A high spool includes a high pressure turbine that drives a high pressure compressor. The high pressure compressor is a nine stage high pressure compressor and includes a pressure ratio per stage of greater than or equal to 1.20 and less than or equal to 1.33.

A gas turbine engine includes a fan section that includes a fan with fan blades. The fan section drives air along a bypass flow path in a bypass duct. A gear reduction is in driving engagement with the fan and has a gear reduction ratio of greater than 3.0 and less than 4.0. A low spool includes a low pressure turbine that drives a low pressure compressor and drives the gear reduction to drive the fan at a speed slower than the low pressure turbine. The low pressure compressor is a five-stage low pressure compressor. The low pressure turbine is four-stage low pressure turbine. A high spool includes a high pressure turbine that drives a high pressure compressor. The high pressure compressor is a nine-stage high pressure compressor. The high pressure turbine is a two-stage high pressure turbine.

A gas turbine engine includes a fan drive turbine driving a low pressure compressor, and driving a gear reduction to in turn drive a fan rotor at a speed slower than the fan drive turbine. The turbine section further includes a high pressure turbine driving the high pressure compressor. The fan drive turbine and low pressure compressor are connected by a shaft and the fan drive turbine, the shaft and the low pressure compressor define a low pressure spool. The gas turbine engine is rated to provide an amount of thrust at maximum takeoff, and a low spool thrust ratio defined as a ratio of a torque on the low pressure spool at maximum takeoff in ft-lbs and the maximum takeoff thrust being defined in lbf, with the low spool torque ratio being greater than or equal to 0.70 ft-lb/lbf, and less than or equal to 1.2 ft-lb/lbf.

A gas turbine engine includes a fan drive turbine driving a low pressure compressor, and driving a gear reduction to in turn drive a fan rotor at a speed slower than the fan drive turbine. The turbine section further includes a high pressure turbine driving the high pressure compressor. The fan drive turbine and low pressure compressor are connected by a shaft and the fan drive turbine, the shaft and the low pressure compressor define a low pressure spool. The gas turbine engine is rated to provide an amount of thrust at maximum takeoff, and a low spool thrust ratio defined as a ratio of a torque on the low pressure spool at maximum takeoff in ft-lbs and the maximum takeoff thrust being defined in lbf, with the low spool torque ratio being greater than or equal to 0.70 ft-lb/lbf, and less than or equal to 1.2 ft-lb/lbf.

A fan section includes a fan with fan blades. The fan section drives air along a bypass flow path in a bypass duct. A gear reduction is in driving engagement with the fan and has a gear reduction ratio of greater than 3.0 and less than 4.0. A low spool includes a low pressure turbine that drives a low pressure compressor and drives the gear reduction to drive the fan at a speed slower than the low pressure turbine. The low pressure compressor is a four-stage low pressure compressor. The low pressure turbine is a three-stage low pressure turbine. A high spool including a high pressure turbine that drives a high pressure compressor. The high pressure compressor is a nine-stage high pressure compressor. The high pressure turbine is a two-stage high pressure turbine. An exhaust gas exit temperature of greater than 900 degrees Fahrenheit and less than 1000 degrees Fahrenheit at maximum take-off.

A fan section includes a fan with fan blades. The fan section drives air along a bypass flow path in a bypass duct. A gear reduction is in driving engagement with the fan and has a gear reduction ratio of greater than 3.0 and less than 4.0. A low spool includes a low pressure turbine that drives a low pressure compressor and drives the gear reduction to drive the fan at a speed slower than the low pressure turbine. The low pressure compressor is a four-stage low pressure compressor. The low pressure turbine is a three-stage low pressure turbine. A high spool including a high pressure turbine that drives a high pressure compressor. The high pressure compressor is a nine-stage high pressure compressor. The high pressure turbine is a two-stage high pressure turbine. An exhaust gas exit temperature of greater than 900 degrees Fahrenheit and less than 1000 degrees Fahrenheit at maximum take-off.

A gear reduction drives a fan rotor at a speed slower than a fan drive turbine. The turbine section further includes a high pressure turbine driving a high pressure compressor. The fan drive turbine and low pressure compressor are connected by a shaft and the low pressure turbine. The shaft and the low pressure compressor define a low pressure spool, the low pressure spool has a torque at maximum takeoff defined in ft-lbs and also having a low pressure spool power defined in horsepower and at maximum takeoff, and a ratio of the low pressure spool torque to the low pressure spool power being defined, with the low pressure spool power being defined in horsepower, and the ratio of the low pressure spool torque to the low pressure spool power being greater than or equal to 0.6 ft-lb/hp and less than or equal to 1.2 ft-lb/hp.

An apparatus for oil lubrication of a rotationally fixed connection between two shafts. A first shaft engages with a hollow region of the second shaft. The shafts are operatively connected to each other in a form-fitting manner in the overlapping region. Oil is introduced into a first chamber in the hollow region, which chamber is connected to a second chamber in the hollow region. The second chamber is connectable to a third chamber is arranged in the overlapping region. The fluidic connection between the second chamber and the third chamber is separated above a defined oil volume in the second chamber and above a rotational speed threshold of the shafts via a sealing element. The sealing element is reversibly deformable by the oil volume in the second chamber and the centrifugal force acting thereon and, in the deformed state, seals the connection between the second and third chambers.

An apparatus for oil lubrication of a rotationally fixed connection between two shafts. A first shaft engages with a hollow region of the second shaft. The shafts are operatively connected to each other in a form-fitting manner in the overlapping region. Oil is introduced into a first chamber in the hollow region, which chamber is connected to a second chamber in the hollow region. The second chamber is connectable to a third chamber is arranged in the overlapping region. The fluidic connection between the second chamber and the third chamber is separated above a defined oil volume in the second chamber and above a rotational speed threshold of the shafts via a sealing element. The sealing element is reversibly deformable by the oil volume in the second chamber and the centrifugal force acting thereon and, in the deformed state, seals the connection between the second and third chambers.

A turbofan engine is provided. The turbofan engine includes a fan comprising a plurality of rotatable fan blades, each fan blade defining a fan tip speed; a turbomachine operably coupled to the fan for driving the fan, the turbomachine comprising a compressor section, a combustion section, and a turbine section in serial flow order and together defining a core air flowpath; and a gear box, wherein the turbomachine is operably coupled to the fan through the gear box, wherein a gear ratio of the gear box is greater than or equal to 1.2 and less than or equal to 3.0; wherein during operation of the turbofan engine at a rated speed the fan tip speed is greater than or equal to 1000 feet per second. In exemplary embodiments, during operation of the turbofan engine at the rated speed the fan pressure ratio is less than or equal to about 1.5.