NASA’s Ageing EMU Spacesuit & Problems With Future Plans
A spacesuit is a necessary piece of technology when leaving the safety of the astronaut’s habitat or spacecraft environment. Here they are directly exposed to the harsh and deadly conditions of space. This features not only the lack of air, but high and low temperatures, radiation, and more. Once completed a spacesuit is practically a designated spacecraft for individual astronauts to perform various necessary tasks in.
For quite a while now NASA has been using spacesuits for a wide range of reasons. This could be to repair the Hubble Telescope, work on the International Space Station, and much more. However, the current EMU spacesuit is quite old and is causing concerns for quality, convenience, and most importantly safety. This adds additional bad news to the delay of NASA’s upcoming xEMU spacesuits.
With space stations such as the ISS getting a potential extension of operation up until 2030, the demand for a new and improved spacesuit continues to grow. While the xEMU is planned for use on Artemis and future missions, that would not be its only purpose at all. In reality, NASA needs to figure out exactly when and how they can access new spacesuits and decommission past models.
NASA Spacesuit Background
EMU stands for Extravehicular Mobility Unit and is an independent anthropomorphic spacesuit that provides all of the astronaut’s needs to not only stay safe but operate within the vacuum of space. Specifically, an EMU is used for an extravehicular activity or EVA in Earth’s orbit and more. After receiving a contract to build the EMU in 1974, Hamilton Standard and ILC Dover delivered the first suits to NASA in 1982. During the research and development phase, there were multiple problems including a suit being tested that caught fire and injured a technician. This ended up forcing a redesign of the regulator and circulation fan. Not long after the first Shuttle EVA was to occur but an electrical failure on the circulation fan forced the EVA to be canceled.
After some time the first EVA of the EMU occurred when astronauts went out in the payload bay of the Space Shuttle Challenger and tested techniques to lower the launch cradle. Prior to the construction and assembly of the International Space Station, the EMU suits got the majority of their use for repairing and servicing the Hubble Space Telescope. For these missions, two sets of EVA astronauts would venture out of the orbiter which required NASA to fly four sets of suits for each mission. All together 41 EVAs using EMUs had been conducted out of the Space Shuttle airlock prior to the start of ISS assembly. When starting to build the ISS, upgrades were made to the existing EMU by making the suit modular. This allowed an EMU to be left on the ISS for up to two years and resized on-orbit to fit various crew members. They also improved a long list of items including battery capacity, cameras, radios, warning systems, and more.
The Ageing EMU
In 2017, NASA’s Office of Inspector General reported on NASA’s need to replace the aging EMU fleet so astronauts can safely continue ISS missions through 2024. With a potential extension of ISS operations through 2030, the need to replace the current EMU suits increased significantly. As I mentioned prior, these current suits were developed in 1978 during the Space Shuttle Program, Since then, the spacesuit has been maintained to extend its usability deceased beyond its initial 15-year lifespan. Currently, the agency is managing the design and health-related risks associated with the EMUs, including the constrained Hard Upper Torso sizing that limits which astronauts can participate in extravehicular activities. Along with ongoing risks, the Office of Inspector General documented in their 2017 report broad categories of significant incidents including dangerous water intrusion and carbon dioxide problems.
In addition to these NASA is tracking two other primary risks such as decompression sickness and thermal regulation. All of which are necessary and can cause serious injury or worse if it happens in the wrong environment. It’s also important to point out that the spacesuits have caused astronaut shoulder and hand injuries and have failed to provide sufficient nutrition and hydration while in use. Years ago the Safety Advisory Panel recommended NASA immediately transition the EMU to the xEMU system, cautioning that “continued use of the aging suits is too risky for astronauts.” NASA ended up agreeing with the panel however the accelerated timeline for landing on the Moon gave rise to conflicting priorities with the Artemis Program. For example, if the HLS Program receives the first two xEMU flight suits in November 2024, the ISS program will be further delayed in obtaining needed replacements. Not only are current EMUs dated and dangerous, but they also cost an immense amount of money to upkeep and more. A big part of the EMU is the PLSS or Primary Life-Support System. Of the original 18 units, only 11 remain in inventory to support the ISS program. The maintenance of these 11 units currently costs about $150 million each year under a contract with Collins Aerospace set to expire in 2024.
Problems With Future Plans
Looking past 2024, NASA continues to track a risk affecting the compatibility of the xEMU with the Gateway Program. Once operational, the Gateway will have periods of dormancy of up to 3 years without services or human interaction. During this time the new xEMU will be left inactive and dormant in storage. To put this in perspective, current EMUs are regularly used on the International Space Station, and maintenance is performed on the suits both on the Station and when a spacesuit is returned to Earth after 6 years or 25 spacewalks. While the Gateway Program requires a potential 3-year dormancy period, the xEVA system requirement for dormant storage is 2 years, resulting in a mismatch between the program and the requirements of the suits.
Over the past 14 years, NASA has invested $420 million in next-generation spacesuit development. At the time being, NASA plans to continue the design, development, and maturation of the xEMU. Regardless of NASA’s approach for next-generation spacesuits and extravehicular activity services, future contractors will need to provide suits that are compatible with the ISS, Gateway, and HLS for future Artemis missions. However, with the evolving and competing requirements of the xEMU’s stakeholder programs and the agency’s uncertainties about the mission priorities, NASA is at risk of awarding a contract without clearly defining the key technical requirements. This could significantly slow down the process and increase costs as shown from past examples. All of these different risks and concerns are combining and threatening timelines of future missions. Without proper spacesuit equipment, no human will be stepping foot back on the Moon and more. This is just a part of NASA’s current problem regarding spacesuits and future missions.
Conclusion
Spacesuits are very complicated and important pieces of technology. Currently, NASA is having quite a few problems surrounding this one piece of equipment. The agency is trying to balance a big mix of outdated EMUs, upcoming missions, xEMU development, and many different nearing deadlines. A spacesuit is a piece of technology that the agency can not afford to skip or gloss over. They are necessary for any action in the vacuum of space including the most important of keeping the astronaut within safe. Not only are these suits going to be used on future Moon missions but are needed as fast as possible to replace past EMUs. Right now NASA has its plate full and needs to solve its spacesuit problem. We will have to hope for the agency’s success as it will have a direct impact on future Artemis missions, ISS spacewalks, and much more.