Abstract: Approaches are provided that evaluate overall engine thrust and potentially other engine operating parameters statically on the ground for an engine. The results of the evaluation are used to produce a correlated analytical model that accurately models engine performance. Once testing on the ground is complete and correlated model determined, the engine is placed aboard an aircraft and tested in flight. Thrust of the engine can be determined at least in part using the correlated model and this determined thrust is compared to the desired thrust.