PROJECT HIGHWATER

'Project Highwater' was included as part of the test flights of NASA's Saturn I launch vehicle (using battleship upper stages), and two flights were successfully launched into a sub-orbital trajectory from Cape Canaveral, Florida. The first was on April 25th 1962 SA-2 (Apollo) and the second on November 16th SA-3 (Apollo) of the same year.
Once the flight tests on the rockets were complete, after the first stage shutoff (at 65 miles in altitude for the first flight and 104 miles for the second), the water-filled upper stages were exploded causing 95 tons of water to be ejected into the upper atmosphere. The resulting massive ice clouds expanded to several miles in diameter and lightning-like effects were recorded. The 'Highwater' experiment, was intended to investigate the effects on the ionosphere of the sudden release of a great volume of water, however poor telemetry on the second flight made the results questionable. [1] [2] According to a historian, the project answered questions about the effect of the diffusion of propellants if a rocket exploded/was destroyed at high altitude. [Bilstein, Stages to Saturn: A Technological History of the Apollo/Saturn Launch Vehicles, (Univ. of Fla. Press, 2003) pg. 325 (note: this book was apparently previously published as an official NASA publication; NASA SP-4206 and NASA 033-000-01176-8)]