The simulator < Swell Delay > depends on equations which are based on the fundamental laws of Physics, of Chemistry, and of Rock Mechanics.  It simulates the displacement of the rock at the rear of the bench of a front row, as well as that of the front of the bench of a rear row; by comparing the displacement of the rock at the rear of the bench of a front row with that of the front of the bench of a rear row, for a given value of the delay between rows, one obtains the horizontal swell for that delay.  The simulations are repeated for different values of delay till the horizontal swell is adequate to move the rock of a rear row without causing excessive upward flyrock; the value of the delay which gives this adequate swell represents the Necessary Delay.

The simulator < Swell Delay > is presently not accessible on the Web, but it will be so accessible very soon.  Until then, it is possible to obtain the results on request.  Note:  The simulations with the various Flyrock simulators assume that the delay between rows is adequate to satisfy the condition of Necessary Delay.