How do these simulators work? What is the underlying model that gives sim users assurance that the simulated behaviour corresponds to real world aerodynamics and eg engine behaviour?
There are several levels of "Full Flight Simulators" [1] defined by the FAA: "There are currently four levels of full flight simulator, levels A - D, level D being the highest standard and being eligible for zero flight time (ZFT) training of civil pilots when converting from one airliner type to another."
The requirements and process for testing simulators for certification is documented as well [2]. Its not clear from the article exactly what simulator they were using though.