Cathleen Lewis, Curator, National Air and Space Museum
|B.F. Goodrich’s Mark IV suit developed for the U.S. Navy. Photo by Mark Avino, National Air and Space Museum|
American spacesuits have not one but three technological ancestors, and the National Air and Space Museum's collection illustrates this lineage of invention and reinvention since the middle of the last century. During the 1950s, the navy and air force divided the workload for developing aviation flight suits. The navy focused on the development of pressure suits that would protect pilots flying at high speeds and conducting tight maneuvers. These suits' primary purpose was to prevent pilots from passing out when high gravitational forces pulled blood away from their brains and hearts and toward their extremities. B.F. Goodrich's Mark IV flight suit represents the culmination of this work and was the basis for the Project Mercury spacesuits.
Meanwhile, the air force was working on new high-altitude jets that flew close to the edge of the atmosphere, so their pressure suits had to protect pilots from unfiltered radiation and the possibility of emergency decompression at altitudes where there is little air. During the early 1960s, NASA adapted a version of these suits, made by the David Clark Company for the air force, to function as the first space-walking suits of the Gemini Program.
|Harrison Schmitt’s Apollo 17 A7-LB suit. Photo by Mark Avino, National Air and Space Museum|
While the air force and the navy were designing flight suits for pilots, the Litton Corporation was working on the first suit meant to routinely operate in a vacuum. Unlike the armed services suits, Litton's was a hard suit--one made from rigid materials with complicated and flexible joints. During the 1950s, Litton and other vacuum-tube manufacturers needed a suit that technicians could wear while testing the tubes inside a vacuum chamber. Not facing the weight and volume limitations of aviation, these suits were easy to get into, didn't require pre-breathing oxygen, and permitted free movement of all four limbs. Though the concept of the hard suit fascinated NASA spacesuit engineers, the Litton suits were bulky, heavy, and didn't allow for the fine maneuvers that NASA planners anticipated for spaceflight. And they were not suitable for continuous wear for longer than a few hours.
NASA's Apollo engineers and their contractors looked to these three suits for the features needed to create a pressure suit that could operate beyond Earth's atmosphere, function as life support outside of the spacecraft, and provide mobility for astronauts working on the surface of the Moon. In other words, Apollo engineers had to create a spacesuit that could function as a human-fitting spacecraft that allowed its passenger to function autonomously on the surface of another world. The National Air and Space Museum's collection is richest in examples that illustrate the trade-offs that engineers made during the course of Apollo spacesuit development. In many cases, the contract and developmental suits that we have in our collection are the only remaining evidence of these conversations between NASA, its contractors, and the materials and engineering advisers who shaped the program. The culmination of these discussions was a suit that combined elements of life support, protection against the extreme environment of space, and mobility--the Apollo A7-LB spacesuit.
|ILC’s Mark III technology demonstration model, 2007. Courtesy National Aeronautics and Space Administration|
The Apollo Program was not the end of the spacesuit innovation story, however. The development of the space shuttle orbiter and the International Space Station afforded NASA the flexibility of a two-suit system: one a purely emergency, "get me down," escape suit, worn only during launch and reentry, and another more complex suit worn while astronauts work in open space. Today engineers continue the process of invention, combining the lessons learned from Mercury, Gemini, Apollo, the shuttle, and the International Space Station to imagine what the next generation of suits will be able to do. Among the artifacts of this research that the Museum hopes to collect one day is the prototype Mark III demonstration suit that scientists and engineers tested at Cinder Lake, Arizona, as a simulation of lunar exploration. NASA's academic and corporate research and development is focused on the elusive ideal--a spacesuit that is both protective and allows full human function in any environment … and still fits in the confines of a spacecraft.
From Prototype, October 2011