NEED HELP A script to shoot rockets in sequence

Hi, I've been asked to make a script that basically makes rocket launchers fire one after another.
I am not familiar with this game's command block's methods and I have no clue of what I am doing since I only played the game 94 hours. (and stopped)

I have found on the game's wiki that there is no action to make the launcher fire once : http://www.spaceengineerswiki.com/Programming_Guide/Action_List#Rocket_Launcher
Is there a way to do what I said, Shoot a rocket with the command...

NEED HELP A script to shoot rockets in sequence