Turbine engine including an air turbine starter and a bleed air circuit

A turbine engine comprising:

• an engine core including a fan section, a compressor section, a combustion section, and a turbine section, and an engine drive shaft operably coupling the fan section, the compressor section and the turbine section;
• an engine casing housing the engine core;
• an accessory gear box (AGB) disposed exterior the engine casing, operably coupled to the engine drive shaft;
• an air turbine starter (ATS) having an ATS turbine, an ATS gearbox, an ATS drive shaft operably coupling the ATS turbine and the ATS gearbox, and an ATS output shaft operably coupling the ATS gearbox to the AGB;
• and
• a bleed air circuit comprising:
• a first bleed air passage fluidly coupled to the compressor section;
• a second bleed air passage fluidly coupling the first bleed air passage to the ATS;
• a third bleed air passage fluidly coupled to an output of the ATS;
• and
• a bypass passage fluidly coupled to the third bleed air passage while bypassing the ATS;
• and
• a pre-cooler heat exchanger (PCE) fluidly coupled to the fan section and a system external to the turbine engine, wherein the third bleed air passage and the bypass passage meet at a junction upstream of the PCE.