I was taught in engineering school (mechanic school for our USA cousins) that because roughly 70% of mass airflow in a GT engine is used for cooling, humidity effects aren't an issue. Moisture in the air has negligible effects on combustion.
Common sense says that if humidity is, for example 80%, that that amount of moisture in the air must have some sort of effect, so I would be interested in hearing a more technical/ experienced answer also.
Last edited by nodrama; 20th March 2008 at 11:39.