RR Spey used demineralized water and this was injected directly into the combustion chamber by a separate tube but part of the fuel spray nozzle 10 each eng -512-14DW. DW = developed wet.
On the 500 series Bac 1-11 a rear water tank could hold about 500 kg of water. Freezing was a problem and you had tables to use if you wanted to tank water, time in cruise temp at altitude, water temp on loading were considered. Water was a bit of a pain to load downroute so tanking was prefered. If you could not tank then you had to load barrels of water into the hold and pump it into the tank downroute with a portable pump/motor also located in the hold. This pump was stored in a box, and you would drag the thing out and plug the hose into the rear of the aircraft. The plug for the pump was inserted into a socket in the rear freight hold.
As far as perf went you also needed to use tables to determine the amount of water you needed to enable you to climb to 400ft (min flap retract). Again based on temps, airfield alt, and aircraft weight.
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