ratio of the thrust integrated over an appropriate time interval divided by the integral over the same time interval of the product of throat area and throat total pressure
NOTE 1 In accordance with this definition, the average thrust coefficient can be calculated as:
In many cases, t1 is taken to be the ignition time, t0,and t2 is taken the time at burnout (te). In this case, t2 - t1 = tb and the integral of the thrust becomes the total impulse.
NOTE 2 Instantaneous and average thrust coefficients are usually referred to as thrust coefficient