After 18 years of supplying hydraulic calculation software to the sprinkler industry Alan Ashfield has decided to take a well-earned rest. Many of us in the sprinkler industry (well those of a certain age) will remember the days before computers, when hydraulically calculated systems were less frequent not because it would not have reduced pipe sizes or resulted in smaller pumps but because the term ‘fully hydraulic system’ made many people weak at the knees. This was the time when full hydraulic calculations were considered a ‘dark art’ performed by few using strange tables or peculiar slide rules. But unknown to us then, two Alan’s were planning a revolution.