FT, 20 years ago the main method of achieving simulator "fidelity" was to run a series of flight tests on an actual aircraft (one selected from the fleet) that involved taking a series of measurements on a number of parameters. They included things like various engine parameters including fuel consumption (each engine was modeled separately), airframe acceleration at various weights, climb rates, roll rates, pitch rates, stick forces at various altitudes and air speeds, trim responses (at various airspeeds and CGs) and a variety of other parameters.
Then the software designers would "model" the simulated aircraft's flight characteristics after the "tail number" of the aircraft that was measured in actual flight. I remember once doing a sim install in Germany for an E-3A AWACS where a Canadian Air Force test pilot was on loan to NATO to do the flight testing of the sim. It was his job to make sure the performance parameters of the sim matched the measured flight parameters of the actual aircraft. I remember having several interesting discussions with him about this, which is why I remember this particular incident the best, even thought flight fidelity was not my area. There was a long series of sign off checks in the sim's contract that he had to approve in the flight parameters area, and it took a good number of days to perform all of the measurements on that sim.
I think that's why sims have an "assigned" tail number for the actual aircraft they were modeled after. I assume that today, 20 years later, this is still the basic process.
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Safe flying to you...
[This message has been edited by Flight Safety (edited 08 February 2001).]