Does anyone know what the first use of a water deluge system was?
I've done some light googling and discovered that the Titan II ICBM rocket silos (first built in 1962) used a water deluge system, but I'm not finding anything on if the Gemini launches used water deluge. From pictures and video, it doesn't look like it.
"Since the Titan II was designed to be launched from within its silo without first being lifted to the surface, unlike all previous liquid-fueled ICBM and IRBM missiles, the silo design required several unique engineering solutions. Among these problems was the dissipation of the 5000 degree F engine exhaust gases, and the reduction of the tremendous acoustical energy generated by rocket engine operation within an enclosed space. Huge ducts and a water deluge sound suppression system prevented the missile from self-destruction due to accoustical energy."
The earliest reference I have found is to LC-34 (built in 1960), used for Saturn I and IB launches.
"A torus ring of large water nozzles, designed by Edwin Davis, encircled the 8-meter-wide exhaust opening. During launch and for some seconds thereafter, the nozzles would spray water on the pedestal, across the exhaust opening, and down the opening's walls, cooling the deflector and pedestal."
This ring is visible in pictures of the remains of LC-34.
The Saturn V launch pads had a "water suppression system" that sprayed water on the pad to prevent damage that was effectively a pad deluge system.