1. A training system, the training system providing training on operation of a vehicle to a trainee, the training system comprising: a computer, the computer having a storage device; a plurality of training segments stored on the storage device and accessible by the computer; one or more graphics displays; a sensor, the sensor configured to measure at least one biological indicator of stress in the trainee; software running on the computer, the software presents the training segments to the trainee, simulating operation of the vehicle; the software reads data from the sensor and the software calculates a stress level of the trainee from the data; and the software modifies operation of the training system based upon the stress level of the trainee.