i was advising some young pump operators when the engine is at a hydrant to put on gate valves on the 2-1/2's when hooking up the 5" espically when you will be pumping a big fire. i was taught this when i was young and in my carrear it has served me well.
one of the last large fires i pumped i caught a really good blue top hydrant and took the time to use the 2-1/2 connections with 2 3" lines in addition to the 5" connection. for several hours i was able to supply a single 5" hose 1100ft to a manifold that went to an aerial and two ground monitors.
i caught a little static being told that "that takes too long to hook up". what i really did was use 2 gate valves on the duce and a halfs of the hydrant and wasted no time making the 5" connection and starting flow. i added the 3" afterwards
anybody agree or disagree with the practice? i estimated my flow in excess of 1500gpm