AMP - Aviation Maintenance Technician Powerplant Practice Exam

EGT thermocouples are designed to measure the exhaust gas temperature of a turbine engine. These thermocouples are constructed of chromel and alumel, which are types of alloys specifically designed for high temperature applications. While iron and constantan is commonly used in other types of thermocouples, they are not suitable for measuring high temperatures in turbine engines. Copper and constantan are also not suitable for this application, as they have a lower melting point and can easily be damaged by the extreme heat of the exhaust. D is incorrect because thermocouples are indeed constructed of specific alloys, and not none of the above.