The physics behind the Stromboli bomb trajectory program

The program calculates trajectories step by step as a ballistic flight. If the check box "include air resistance" is ticked, it also takes into account air resistance (Fa):

Fa = 0.5 * c * d * v2 * A

whereby:
c = resistance parameter, depending on the object shape
d = air density
v = velocity
A = cross section area of the bomb.

The bomb continues to fly over a given landscape profile until it hits the ground or the sea. The program is based on the simplifying assumption that the bomb travels through stationary air as soon as it leaves the crater.

The air density d is variable and is calculated as:

d = 1.2255 * ( 1 - ( 0.00651 / 288) * h )4.255

whereby
h = altitude above sea level
assuming a temperature of 15°C at sea level.