“Next we have loss of gas pressure.” This seems most likely to me if there was some mechanical event, which is likely given Dr. Moss’s message that the Pheia had hit the wall.”
He saw some nods and continued. “And we know that the most exposed parts of the Pheia are the gas cylinders and associated pipe work. Damage to the gas pipes on top of the cylinders seems likely if the impact was hard enough.”
Williams continued with the rest of the items. There was little conversation as most of the discussion had taken place earlier when they made the list.
They finished the list of potential problems. Williams really didn’t know what to do now. “Now we wait.” He said. It seemed a bit obvious, but with the Pheia over 2,500 feet down there really was nothing else to do.
Kate pulled off her dive suit and hung it over the pipes in the ops room. At the control console she saw the message from the surface. She ignored it. She wanted to know if the state of the gas system had changed. As Kate cycled through the gas system screens, she saw that there had been no change in the oxygen or helium systems. The hydrogen system was also, sadly, in the same state it was before her dive. The hydrogen tanks were empty. The carbon dioxide scrubber seemed to be OK. She went to the main gas system screen. Her hands fell to her side and she stared at the screen. The gas mix reading was red now. It had been green when she went outside. She tapped on the red indicator and a popup appeared listing the gas mixture percentages. They were all green except for the hydrogen which was about 80% of the value it should be at.
“Where did it go?”
The other gases were in the correct proportions. There must be a leak somewhere but she hadn’t seen it outside. Perhaps it was leaking earlier and had stopped now? Why would it do that? Whatever the reason, she now had less hydrogen in the mix than she needed to keep HPNS from affecting her. Maybe at 1,500 feet she could breathe just a heliox mix but down here she needed the hydrogen. And the meds. She had forgotten about the HPNS meds again. Could they compensate for the lack of hydrogen? She really needed help.
Kate remembered the ELF message she had seen when she was getting out of her dive suit and tapped the menu on the console to bring the message back up. She read Williams’ message and wondered why he was asking for details. “Didn’t he get my report?” she thought and then realized that she had not sent the log entry to the surface. “Might as well do it right.”
Kate spent ten minutes taking a new set of readings and entering them in a new log entry. It gave her a chance to review the overall gas situation once more. It was apparent that there had been a leak going on because the helium level had dropped in the tank. The oxygen level was more or less the same so the oxygen generator must be compensating.
Kate closed out the log entry and went back to the ELF radio screen. She typed out a short message to say she was sending two reports taken about an hour apart. Then she went into the log system and found how to send the logs. Once they were on the way she decided to add another message: “Hydrogen low in mix. Can I use HPNS meds to compensate?” She tapped the button to send it and wondered how long it would take them to reply.
She knew it would be a while. They had a lot to digest. She decided to eat, and started to heat some water while she picked through the freeze dried meals. She lifted one up and smiled. “Chili Mac. Excellent.”
Hydrogen
(2,400 Feet)
On the surface barge, Williams was engaged in conversation with a medical doctor who had been flown out on short notice.
“So Dr. Andrews, can Dr. Moss use the HPNS meds or not?”
“She can certainly use them, and based on my reading of Dr. Ford’s work, she should certainly do so at the depth she is at now, but this is not going to fully compensate for the lack of hydrogen in the gas mix. You understand this is not my area of expertise, but from what I have read, the hydrogen is really the essential component to the gas mix. The HPNS medication Dr. Ford was developing acts as an adjunct to the hydrogen at much greater depths.”
Williams was uncharacteristically blunt. “So she’s screwed then?”
“I don’t really know. She may have enough residual hydrogen in the gas mix for her to get to a depth where it no longer matters. But really, based on the data I’ve seen, she is in a bad position, yes.”
Williams thanked Andrews and walked back to the room he was bunking in. He lay down on the rather short and uncomfortable bed and stared at the ceiling. He had no idea what to tell Kate. She had no hydrogen left and yet that was what she needed for at least the next four or five days. He had considered trying to lower a tank down to the Pheia but they didn’t have a tank readily available, and in any case, Kate might not have the ability to connect it.
Williams lay on his bunk for half an hour thinking before getting up and returning to the comms shack.
When he got there he asked the technician if there had been any more messages.
“No sir. Nothing.”
“Very well. I’d like to send a message myself if I may.”
The technician moved out of the way and Williams sat at the console. He really didn’t want to send this message, but after a lot of thought he had rationalized that Kate had probably already figured out what he was about to tell her, and even if she hadn’t, she’d get there soon.
He typed out the message: “Kate: Sorry but we have no solution to the hydrogen problem. The meds will not compensate for the lack of hydrogen. We will keep working on the problem from up here. Williams. P.S. Keep taking the meds anyway.”
He tapped the button on the console to send it. He stood up looking at the machine hoping for a reply. He wasn’t sure what he was waiting for exactly. He knew it would take Kate a while to digest it.
To his surprise a message appeared while he was watching the screen.
“OK. As expected.”
“Well she knows now,” he said to himself.
“Yes sir. She does,” the technician added from beside Williams. He had watched the exchange.
In the Pheia, Kate watched the ELF screen in case Williams sent anything else, but after a couple of minutes she gave up. She looked out the portal to make sure the Pheia was still ascending and considered her options. She could increase the ascent rate and try to make it to a depth that a straight heliox mix would work for or she could… “What? There are no other options,” she said aloud.
Even if she doubled the ascent rate, it would still take at least two days before she was safe without the hydrogen. But she had no idea if that rate was safe in itself. The last thing she needed now was to get bent or suffer some other form of incapacitation. She was still functioning OK. She had no shakes and her vision was clear. So far as she could tell, her mental processes were working fine too. “So think.”
Kate stared out the portal at the rock creeping past in the Pheia’s lights. “All the hydrogen I could ever need is right there bound up with some oxygen molecules.”
She thought about that for a while. How could she separate the hydrogen from the oxygen in the water? Then she thought about the gas system in the Pheia. It somehow extracted oxygen from the water. That was where the oxygen in the gas mix came from. How did it do that? What happened to the hydrogen that was left after the oxygen was extracted? Perhaps there was a way to tap into that and feed it into the hab’s atmosphere.