The sloshing tanks of coloured water being tested here offer insight into the response of a launcher’s liquid propellants to the violence of take-off. Better understanding of the forces involved should help enhance future launcher performance. ESA’s earthquake-strength ‘Hydra’ shaker table – more typically used to check full-sized satellites are fully prepared for take-off – was selected for ESA’s July 2013 slosh test campaign because of its high controllability.