Fan arrangement for a gas turbine engine

A gas turbine engine for an aircraft comprising:

• an engine core comprising a turbine, a compressor, and a core shaft connecting the turbine to the compressor;
• a fan located upstream of the engine core, the fan comprising a plurality of fan blades extending radially from a hub, each fan blade having a leading edge and a trailing edge;
• and
• a gearbox that receives an input from the core shaft and outputs drive to the fan so as to drive the fan at a lower rotational speed than the core shaft;
• and wherein:
• the turbine comprises a lowest pressure turbine stage having a row of rotor blades, each of the rotor blades extending radially and having a leading edge and a trailing edge;
• wherein a fan-turbine radius difference is defined as the radial distance between:
• a point on a circle swept by a radially outer tip of the trailing edge of each of the rotor blades of the lowest pressure stage of the turbine;
• and a point on a circle swept by a radially outer tip of the leading edge of each of fan blades;
• and a fan speed to fan-turbine radius ratio defined as:
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• turbine
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• wherein the fan speed to fan-turbine radius ratio is in a range between 2.9 rpm/mm and 3.8 rpm/mm, and a fan tip radius of the gas turbine engine is in the range from 110 cm to 150 cm.