As she pushed up into an up-dog, she looked through the portal on the far side of the room. She could not quite see the wall, just a bright area of light reflected back from it. Something about that got her curiosity and she gave up on the pose and stood up.
At the portal, she noticed that the wall had stopped moving. Two steps over at the console she confirmed that the ascent rate was set to zero. Had she done that? No. At least she didn’t think so. No. Certainly not. The last thing she had done at the console was what? She couldn’t remember.
Her heart started pounding. “Calm down.” she said aloud, and tapped the menu until she had the gas system page. A brief scan showed everything was green. She held her hands out in front of her and studied them. They had a slight shake. Not surprising given her heart rate.
Kate closed her eyes and breathed deeply forcing her breath out between her lips in long, slow cycles. She felt her heart slow down and her composure return. When she opened her eyes and looked at her hands again they were steady. “HPNS?” she thought. The depth indicator showed a little under 1,400 feet. That made her feel better. Not only was she getting closer to the surface but she was now at a depth where the hydrogen in the mix wasn’t such a necessity and she would not need to inject herself with the meds again. That alone, was worth being happy about. She didn’t like injections when someone else was doing them, and she had found that they were worse when she had to do them herself.
“So why have we stopped?”
She closed her eyes again and listened for the noises of the drive motors. They were still there holding the Pheia motionless. Kate could hear the occasional bursts of activity that corrected for drift or changes in attitude of the hab. So the drive system was operating OK.
Out of the portal, the wall was where it had been for days. Kate pressed her face against the plastic and looked up. The wall disappeared up into darkness as far as she could see which wasn’t far past where the top of the hab was.
Back at the console she opened the log screen and scrolled down to the last entries. There it was. “Ascent halted. Overhead obstruction.”
“Oh crap. What now?”
She tried looking up from the portal again but there was nothing to see.
Her options seemed limited. She could try to manually move the Pheia out away from the wall and see if she could restart the ascent. Or she could go out there and see what the problem was. The dive was not very enticing so she toyed with the idea of moving the Pheia laterally. Or maybe down a bit and then out a way? Her mind went into overdrive thinking of all sorts of obstacles that could tangle up the top of the Pheia. “OK, we need to go and look.”
On the support barge, Williams was on the bridge with the captain and the sonar operator.
“So it’s stopped moving? Is that what you are saying?” Williams asked.
“No, not exactly. We were tracking the Pheia based on Doppler changes in the sonar signal. It’s very close to the wall so a direct ping response isn’t very reliable. We detect it only because it’s moving. And now the Doppler computation shows zero. So it’s either not there or it’s stopped moving.”
“Very well.” Williams replied. “I will send a message and ask what is happening.”
“I already asked the comms guy to do that.”
“Hmmm. And you have had no reply I assume?”
“Right.”
“OK, then I suppose we must wait and see if it starts moving or Dr. Moss sends us a reply.”
When the ELF radio in the Pheia announced the arrival of the new message Kate was already on her way down through the moon pool exit.
As she followed the now very familiar route out from under the weight stack in the direction of the wall, it occurred to her that the Pheia had reported an overhead obstruction and stopped the ascent. Why hadn’t it done that earlier when it ran into the protrusion from the wall? That would have saved all the work on the hydrogen system.
As Kate came out from under the stack she flipped over on to her back then straightened up so she was facing the ops cylinder. She looked up and to her surprise saw a huge shadow against the faint blue of the surface. Whatever it was, it was enormous. She looked towards the wall, which angled away from her dramatically into some kind of shelf.
A few feet further up, her dive light illuminated the obstruction which took on the familiar form of a sunken vessel. She couldn’t tell what it was exactly, but she could see some kind of superstructure on the far side. She was looking at the bottom of the keel and part of the side of the hull. The part that was visible stuck out from the wall at least sixty feet. As she drew up level with the top of the hab she shone her light along the bottom of the hull and traced it back towards the wall. The light was too weak to see very far so she swam towards where the ship rested on the ledge in the wall.
It was at least 150 feet long and looked to her like some sort of cargo vessel. The Pheia had come up right under it and was now hovering about ten feet below the hull. She still couldn’t figure out why this had triggered the alarm in the Pheia but the wall protrusion had not. Perhaps the rock just hadn’t stuck out far enough?
Kate swam over the top of the edge of the wall following the line of the ship’s hull about 20 feet from it. The hull soon curved away to reveal a broken propeller and a few feet further the wall ascended vertically again. The ship was resting on a huge ledge.
She swam around the stern, then went up over the top of a second propeller and around to the top of the ship which was lying on its port side. She swam along parallel to the deck, which had three large cargo hold openings. Most of the superstructure was missing. It looked very mangled; presumably as a result of sliding down the wall.
When she reached the bow she swam down under it and stopped. The Pheia was below her and towards the wall. Her heart jumped when she realized she wasn’t tied to the Pheia. “That was stupid.” At least it was still there.
Once she was on top of the ops cylinder, she tried to gauge how far she would need to move the Pheia to clear the ship. She looked out away from the wall into the darkness. “OK dummy. We have lots of space.”
Back in the ops room, Kate debated the merits of sending a message to the surface asking for instructions versus simply moving the Pheia without their guidance. She had spent quite a bit of time looking at all the control systems in the past few days. She was familiar with the vertical ascent rate controls and where the wall lateral separation value was entered. “It can’t be that hard.” she said aloud, and decided to do what she had done when Boris was trapped and just set up a larger separation value from the wall and see what happened.
On the bridge of the support barge the sonar let out a ping and everyone looked at it.
“What was that?” Williams asked.
The sonar operator was already looking at the display.
“We got a direct return from something. It’s at the right depth for the Pheia but it’s not right.”
“Why not?” Williams asked.
“Sorry. It might be right. It’s just different. This is a clear response with no Doppler shift. The only way we could get that is if the Pheia was a long way from the wall.”