EVA #7 Report
Note: Before reading, know that no one was harmed, no rovers or property was damaged, and that as of now, the only thing that is out of place, is the red ATV that is sitting alone on Copernicus Hwy about ~0.8 km south of Sagan St. Now on with the report…
I’ll start from the beginning as usual. We were informed by Shannon before our EVA that the tank in the Red ATV was in fact, half full, and would be able to make the trip to yellow moon and back. We were also informed that it had a reserve gas tank, in the event the first one ran out. There’s a knob on the left side that the rider is supposed to be able to turn to access the reserve fuel. Knowing this, I thought that in the event of running out of the first tank we’d be fine. We were not!
Camila, Atila, and I began our EVA began at 11:45, shortly after the four new rovers were delivered. Our goal was to collect a few of plant & regolith samples in the yellow/green moon area. I led with the ATV, with the rover behind, careful to stay within sight and contact range. We took our first two samples without incident, photographing each site for future coordinate reference. After leaving the green mars area, I stayed within contact range to see if they wanted to stop along the way. Much of the landscape near the road was rather devoid of vegetation, so we continued down to Sagan St. I was aware at this point that this was much further than we had planned to go, but I wanted to make sure Camila got all the samples she needed.
We continued about 4 and a half kilometers south, until we could see cars passing by on Hwy 24. I knew we were far, but as far as I knew, the rover was stated to have a 25 mile range, and the ATV probably has at least a 2 gallon tank, and that last gallon would be able to get the ATV back. After all, even if it did run out, I still had that extra reserve tank right?
So about 0.8 km south of the Sagan St and Copernicus Hwy junction, the ATV ran out of gas. I tried to use the switch that would siphon the reserve fuel tank, but I couldn’t get it to turn. It had an “off” and an “on” position that I could turn it to, but whenever I tried to get it to turn from “reserve” to “fuel”, it wouldn’t budge. We tried starting it at the “off and “on” positions to see if that did anything, but no luck.
I realized now that I was on a three person EVA with a two-seater rover and a non-functioning ATV, which meant we had to leave someone behind. I painfully regret having to do that, but I knew that trying to transport a crew member in the cargo bin was not an option. I couldn’t stay behind because we’d need my navigational knowledge to get the rover back, and there was no way I would have Camila stay. So we unfortunately had to leave Atila behind with the ATV. The plan was to return to the hab, charge Deimos to full power, rescue Atila, and bring him back home. I was informed that Deimos could charge relatively quickly, within a couple of hours. It was risky, but we had to try it. We made this decision at about 1:30 PM.
I drove the rover, making sure it was driving in Medium. We passed Sagan St, Green, Yellow, & White Moon, making it to the main road. I was concerned because the rover’s charge was dropping fast, faster than it should have been. This was very surprising, because, after driving nearly all the way down to Hwy 24 on Copernicus Hwy, turning around and stopping where the ATV ran out of fuel, the rover’s charge was at 63%, at 18 km. Keep in mind, that Deimos was at full charge when we left the Hab.
By the time we got to Tank Wash, it was reading in the low 20% range. By the time we got to the Reservoir, it wouldn’t even give us a battery reading, only displaying “Low Battery”, and flashing a red light. I soon realized that the vehicle was starting to have a really tough time going up hills, especially when trying to climb up the road near the reservoir. For a moment, it seemed like we wouldn’t make it up, but luckily we barely managed to make it to the top. As we passed Galileo Rd, the power output continued to decrease, making me doubt if we could even make it to the hab at all. By the time we rounded Pooh’s corner, I felt like we were going as slow as one of the actual rovers on Mars. The rover was just barely crawling along now. Even the slightest bump or divot in the road would almost bring it to a halt.
Now that the hab was in sight, we attempted to establish contact with anyone listening. No response.
So we manage to make it to the hab, within an inch of the battery giving out. It barely had enough juice to go over some uneven ground, just so I could park it. We plugged it into the extension cord to charge it. We attempted to contact the hab once again.
At this point, more concerned about our stranded crewmember than with Sim, we attempt to contact Shannon, but to no avail.
So we decide that our only option is to break Sim and contact Shannon. We entered through the Northern Airlock, to Carmen, who was very surprised to see us. It seems that neither Carmen nor Julio had heard our transmission. As neither of them had a walkie talkies on them, this is another issue that’d have to be resolved later. The time now is about 2:40 PM.
Now that Sim was broken, we went to Shannon and told her everything. The plan now was to get gas from town, come back, deliver the gasoline to Atila with Deimos, so he could drive back under his own power.
So Carmen and I took the Hab Vehicle into town, retrieved the gas, and returned to the Hab. But now, there was a new problem, Deimos wasn’t charging. It was still reading “low-battery” on its display screen instead of a proper battery reading. What this meant was that none of the rovers would be able to deliver the gasoline to Atila, and safely return to the Hab. Not to mention, the road through the White Moon area was far too treacherous for the Hab Vehicle to get through. So I showed Shannon approximately where he was on the MDRS map, and we decided the only way we could get the gasoline out to him, was to carry it out there on foot.
Luckily for us, we wouldn’t have to take the same route the rovers did, as we could just climb up to hab ridge, and beeline it towards the stranded ATV. A direct route on this path would be over 2 km away, which could take up to an hour. So Shannon, Julio, and I set out with the gasoline, and made our way up the steep, unstable slope. We reached the top of Hab Ridge at approximately 3:20 PM, carefully searching the landscape for any sign of our stranded crewmate and ATV. Soon, we spotted what looked like a black dot, just southeast of Skyline Ridge. We moved as quickly as we could, with a gasoline tank in hand.
After nearly 40 minutes of walking across the open landscape, we made it to Atila, who was still in his full gear and spacesuit after all this time. We filled up the tank to the ATV, and attempted to start it.
Unfortunately, it seemed now that the ATV wouldn’t start. Instead we heard what sounded like clicking noises near where the battery was. We thought that maybe if could check the battery connections that we could get it started. That didn’t work. Then we tried to put it in 1st gear, and see if we could push it and get it going. That didn’t work either. So we resolved to leave the ATV behind and return to the Hab with Atila.
The return trip went without incident. We got everyone back and no one was hurt. Shannon told us that she would have to rescue it from the vast emptiness tomorrow.
We learned quite a bit of useful information during all this that I think is important to share. As I stated before, I had assumed that the Rover had a range of 25 miles as stated before, and that the ATV would have enough juice, as well as a reserve tank, to return home. My assumptions obviously led to all the events described above, and could have potentially endangered my crewmates. This means that I have to plan future EVAs much more carefully. Now that we do have ethanol-free gas available, we will be able to top it off before starting each EVA. I calculated that the ATV must have covered about 18 km before running out of fuel. If the ATV was indeed at half level as estimated, then that means a full tank only has a 36 km range. My recommendation would be to turn at 15-16 km out, assuming anyone could even get that far from the Hab by road.
What happened with Deimos’ was very surprising to me. It seems that after a certain point, the rover looses its charge at a faster rate. The total distance the rover traveled I calculated to be about 29 km, or 18 miles. It’s my recommendation that EVAs involving Deimos should not go out further than 12-13 km, even of the battery guage is reading over 60% charge.
Also, regarding our inability to communicate with the hab, it is critical that the In-Hab and EVA communication equipment is thoroughly tested. Although went through our routine Comms test before the start of our EVA, we didn’t check to make sure that the walkie-talkies in the Hab had their volumes loud enough. I think from now on that any crewmembers that are staying in the Hab during EVAs should have a walkie-talkie on their person, at all times, until the EVA party is safely recompressed through the airlock.
This is all I have to report on the events of today. If you have any questions or concerns, please contact me.
Prepared by Brandon Ferguson