Turbofan engine with power extraction system

A power extraction system (200) is disclosed having a forward fan stage (52) configured to pressurize an airflow (1), an aft fan stage (60) having a tip-fan (70) configured to pressurize a first portion (3) of a pressurized air flow (2) from the forward fan stage (52) wherein the aft fan stage (60) is driven by a second portion (4) of the pressurized airflow (2), and a power drive system (210) adapted to supply power from the aft fan stage (60).