The Saturn I SA-2 mission marked a significant milestone in the history of space exploration. Launched on April 25, 1962, this mission was the second test flight of the Saturn I rocket and was part of the Apollo
program. It was notable for conducting Project Highwater, an experiment designed to study the ionosphere by releasing a large quantity of water at high altitude. This article delves into the historical significance and technical achievements of the Saturn I SA-2 mission.
Launch Preparations and Challenges
The preparations for the Saturn I SA-2 mission began on February 27, 1962, at Cape Canaveral, Florida, with the arrival of the second Saturn I launch vehicle. The mission faced several minor challenges during the preparation phase, including a leak detected between the liquid oxygen dome and injector for the #4 H-1 rocket engine. Despite attempts to fix the issue, the decision was made to proceed with the launch without replacing the engine. Other minor problems included issues with the guidance subsystem and service structure operations, damaged strain gauges, and a manhole cover on the dummy Centaur third stage that needed replacement.
Despite these challenges, none of the issues required the launch date to be postponed. The mission proceeded as planned, demonstrating the resilience and adaptability of the team involved in the Saturn I SA-2 mission.
The Launch and Flight Details
The Saturn I SA-2 was launched at 14:00:34 UTC on April 25, 1962, from Launch Complex 34. The countdown sequence experienced a 30-minute hold due to a vessel entering the flight safety zone downrange. The rocket carried 619,000 pounds of propellant, about 83% of its maximum capacity. The H-1 engines shut down at an altitude of 35 miles after firing for 1 minute and 55 seconds, reaching a maximum velocity of 3,750 miles per hour.
The vehicle continued to coast to an altitude of 65.4 miles, at which point, 2 minutes and 40 seconds after launch, officials sent a terminate command to the rocket, causing it to destruct. This controlled destruction was part of the mission plan and allowed for the successful execution of Project Highwater.
Project Highwater and Its Impact
Project Highwater was a secondary objective of the Saturn I SA-2 mission. It involved the intentional release of ballast water from the second and third stages to investigate the nature of Earth's ionosphere, noctilucent clouds, and the behavior of ice in space. The dummy upper stages contained approximately 190,000 pounds of water, simulating the mass of future payloads.
Upon receiving the terminate command, dynamite charges split the second stage longitudinally, instantly releasing its water load. Primacord charges created several holes in the third stage, releasing its water over several seconds. Cameras on the ground recorded the water cloud, which dispersed from vision within an average of five seconds. The cloud produced lightning-like effects, described by Dr. Wernher von Braun as "probably the first synthetic thunderstorm ever generated in space." Project Highwater was declared a success, contributing valuable data to the understanding of the ionosphere.
