1. A system to optimize cleaning of a turbine engine, the system comprising one or more computing devices configured to: by a communication link between a turbine engine and a cleaning schedule optimizer, receive engine health data from the turbine engine over time during operation of the turbine engine; by the cleaning schedule optimizer, periodically execute an cleaning optimization routine to evaluate instances of the engine health data using one or more cleaning schedule optimization criteria; and in response to one or more instances of the engine health data meeting an engine health criterion, cause a foamed cleaning agent to be discharged into the turbine engine according to an optimized engine cleaning schedule.