A system platform for an aircraft, the system platform comprising a gas turbine engine including a compressor , a combustor , and a turbine, the combustor adapted to combine air received from the compressor with fuel and to burn the fuel to supply high pressure gasses toward the turbine to rotate an output shaft of the gas turbine engine , a generator coupled to the output shaft of the gas turbine engine and adapted to generate electricity when driven by the gas turbine engine , an energy storage unit coupled to the generator and configured to store the electricity generated by the generator , a control system configured to selectively operate a starter of the gas turbine engine during flight in an aircraft to apply mechanical energy to the gas turbine engine such that a mass flow through the gas turbine engine is increased without increasing a fuel flow rate to the combustor , and a high pressure shaft concentric with and independently rotatable relative to the output shaft, wherein the turbine includes a high pressure turbine rotor coupled to the compressor and the high pressure shaft and a low pressure turbine rotor coupled to the output shaft wherein the starter is selectively operated when a surge margin of the gas turbine engine is below a threshold level, the control system is further configured to determine, in response to a determination that the surge margin is below the threshold limit, whether the gas turbine engine is operating at a maximum capacity, wherein to selectively operate the starter of the gas turbine engine comprises to selectively operate the starter in response to a determination that the gas turbine engine is operating at the maximum capacity, and wherein the starter is coupled to an accessory gearbox configured to transfer mechanical energy from the starter to the high pressure shaft . a gas turbine engine including a compressor , a combustor , and a turbine, the combustor adapted to combine air received from the compressor with fuel and to burn the fuel to supply high pressure gasses toward the turbine to rotate an output shaft of the gas turbine engine , a generator coupled to the output shaft of the gas turbine engine and adapted to generate electricity when driven by the gas turbine engine , an energy storage unit coupled to the generator and configured to store the electricity generated by the generator , a control system configured to selectively operate a starter of the gas turbine engine during flight in an aircraft to apply mechanical energy to the gas turbine engine such that a mass flow through the gas turbine engine is increased without increasing a fuel flow rate to the combustor , and a high pressure shaft concentric with and independently rotatable relative to the output shaft, wherein the turbine includes a high pressure turbine rotor coupled to the compressor and the high pressure shaft and a low pressure turbine rotor coupled to the output shaft wherein the starter is selectively operated when a surge margin of the gas turbine engine is below a threshold level, the control system is further configured to determine, in response to a determination that the surge margin is below the threshold limit, whether the gas turbine engine is operating at a maximum capacity, wherein to selectively operate the starter of the gas turbine engine comprises to selectively operate the starter in response to a determination that the gas turbine engine is operating at the maximum capacity, and wherein the starter is coupled to an accessory gearbox configured to transfer mechanical energy from the starter to the high pressure shaft . <EOS>