To be technically correct a Q400 actually has 4 hydraulic systems. The number 1 and 2 systems, which are the main ones that power landing gear, flight controls etc. the number 3 is a back up if you lose the 1 and 2 systems. It is driven by a DC motor pump and purely operates the left and right elevators. The 4th system is for alternate landing gear extension.
The above scenario sounds like it was straight from the sim. Well done those men (and or women).
