The Art of Preparing for an Analog EVA (HI-SEAS)

The air pumping into the helmet is cool and refreshing, with just a tinge of plastic smell, my torso is cool thanks to cool water running through the tubing in a garment known as a liquid cooling garment. Entering into our airlock I seal the main habitat off from the Airlock by connecting the Velcro on one layer and zipping shut the second.  Turning I can see my EVA companions one, like me, in a fifty pound University of Maryland MX-C  and the other in a modified HAZMAT suit. While we wait five minutes to simulate a decompression of the airlock we are doing last minute checks of communication systems, shoelaces (always important when traversing on a volcano), and equipment to ensure that we are ready to step out the door. This moment is the first official moment of our EVA and like anyone we are excited and anxious to step out of the Airlock, however, this moment is the culmination of many hours work and meetings to ensure a smooth EVA and participant safety.

Left: A liquid cooling garment (LCG), the vest in lined with tubing that runs cool water along the torso of the EVA participant. The black tubing connects the cooler box that holds cold water and is housed in the MX-C’s backpack.

Right: The LCG water cooler is seen in front of the backpack compartment that normally houses the cooler unit.


Mauna Loa offers a site that with geological similarities to the Tharsis region on Mars representing some similarities to what the first Martian explorers may experience. The Hawaiian lava fields contain real dangers, with 100 foot pit craters, crumbling strenuous terrain, lava tubes, and skylights (A portion off dried lava that has collapsed over time revealing a lava tube underneath).  These features are dangerous to normal everyday hikers, so for us in planetary exploration suits that simulate the lack of mobility and additional weight it does not take much for an easy EVA to become a rescue mission.

So how on Earth do we pull off successful Martian EVAs? Planning, patience, and practicality, and no I do not call this the three “P” rule I simply call it smart. Most EVAs start out days in advance with an initial write up called an EVA request/Ops (Operational) Plan. This document details out the EVA’s date, time, main objectives, participants, a detailed route, specific instructions for any actions, no-go criteria, safety concerns, and a predicted timeline. After this document is written it is distributed to the Mission Commander and EVA operations technician (yep me) to be reviewed, edited, and approved. Once approved by internal sources it is time to relay this request to our support staff, the request is sent out with a 20 minute delay and once received by the support staff they will review the document looking for any major safety risks or planning issues. This can take up to several hours and places the EVA team on hold until the go or no-go decision is made. Non-emergency requests are sent out approximately 24 hours in advance, but more urgent requests leave the EVA team sitting with their eyes glued to their inbox waiting patiently (but very vocally) for a response from mission support.  After the all clear and good to go comes back from mission support the real action begins.

The EVA team and internal habitat support (CAPCOM) sit down to review the plan one last time focusing on the objectives, planned route, and any safety concerns. Each person is then assigned one or two of the preparatory tasks.

The required equipment and safety gear for the EVA is collected and stowed in the airlock: generally this is comprised of medical kit, GPS, watch, and any scientific equipment needed for data collection. All the suits have internal ventilation to pull ambient air inside the suit and increase circulation; the MX-C suits also have an additional component for internal cooling using icy water and having this circulate through the liquid cooling garment. These suit components require power and re-charged batteries must be plugged in to test each component individually and then as a group. Once these components work the MX-C suits are packed up securing the battery and water container inside the back pack. The HAZMAT suit uses little battery packs that are secured into waist packs.

Left: MX-C without helmet showing some of the internal support structures all which need to be examined prior to each EVA.

Right: Ventilation and LCG control panel.

Bottom: Battery for the MX-C suits, one battery fully charged can last up to 7 hours.

Each EVA participant also takes a radio/communication system and camel pack filled with water.  After these are tested and prepared the EVA team is ready to start donning their analog planetary suits. The HAZMAT suits are fairly easy to don and require minimal assistance towards the end to ensure proper closure and that all systems are functioning. The MX-C’s are a different story and require a “jackknife” maneuver and at least one other person’s assistance to don the suit. The MX-C’s can take up to 40 minutes to fully don and do a visual inspection prior to attaching the helmet. Occasionally it is at this step that the crew will learn of an issue with a ventilation tube or power switch that has been altered during donning and requires the suited EVA participant to doff the suit for some quick patch work and testing, generally delaying the EVA start time by an hour or more to ensure the suit is properly ready to function.

Once fully suited each participant will do a final communication check, ventilation check, and visual inspection prior to entering the airlock for decompression. Although this might seem redundant, we are simulating exiting into a harsh extreme environment completely not suitable (pun intended) for human life and triple checking systems is vital to ensuring survival in this environment. Now we have come full circle and are back in the airlock waiting for full depressurization to explore our simulated Martian landscape.

Later this week we are preparing to continue exploration of the area, soil testing, sample collection, and an astrophotography EVA and I will be discussing some of the insights into exploring the world around from the comfort of a planetary EVA suit.

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