System and method for monitoring thermal state to normalize engine trending data

This invention relates generally to gas turbine engines and more particularly to monitoring the thermal state in such engines. A method and system for monitoring engine performance in a gas turbine engine uses a plurality of sensors to sense data related to the operation and performance of the gas turbine engine. Selected data parameters from the sensed data are continuously sampled prior to completion of an engine start sequence. The selected data parameters are then evaluated to determine whether specific criteria have been met, and evaluation data are captured whenever the criteria are met. The evaluation data are used to normalize engine performance data to a particular thermal state of the engine. The normalized engine performance data are then trended by comparing it to a parametric baseline for the gas turbine engine.