A streamlined Gemini capsule
With the EVA completed and the hatches safely sealed again, the crew was instructed to allow Gemini 4 to drift and therefore conserve the spacecraft’s propellants. This mode was maintained for the next two-and-a-half days. As a result, the flight plan was continually updated and amended, as a number of operational checks and experiments were scheduled then rescheduled as necessary in real-time. The crew was required to monitor a variety of terrestrial objects or targets and orientate the spacecraft, depending upon the attitude it happened to be in at the time. This affected their performance when operating the experiments and conducting the various checks required throughout the remainder of the mission. A direct result of this was that many of the planned experiments and checks had to be rescheduled to later phases of the mission, when fuel consumption restrictions were lifted. These real-time planning amendments also meant rescheduling the crew’s sleep cycles to suit the new requirements, which in turn required further re-planning of activities around the new sleep periods. While challenging for both the crew and the flight controllers, this was a valuable lesson learnt and clearly revealed the realities of long-duration spaceflight.
- 1.The Gemini Program Physical Science Experiments Summary, Edward O. Zeitler and Thomas G. Rogers, NASA/MSC, September 1971, NASA Technical Memorandum TM-X-58075, p 227Google Scholar