sambolino44
Contributor
I don't know how "near" of a miss you would call this, but the dive definitely did not go as planned. I hope we learn some lessons from this one.
The plan was to do a deep dive, to 90 fsw. We calculated our turn pressure would be higher than rock bottom, and used the largest cylinders available, 100 and 95 cu. ft. We had gotten to about 80 ft nearby, so we figured it was about the same here. Well, it didn't get that deep; we maxed out at 69 fsw. So basically it was a long sideways swim over a mud flat. When we reached our turn pressure, we gave up on the planned 90 feet and turned back. We didn't make it all the way back at depth, and had to ascend in "blue" (actually green) water.
I don't know why, but on this dive the water just seemed "thick". I mean, you know how you glide a bit after you stop kicking? Didn't happen this time; as soon as I stopped kicking I'd stop dead. Weird. There wasn't any current to speak of; I mean it must have been moving something in the vicinity of 8 seconds to go 1 foot. Anyway, the point is, it seemed like a lot of work just to swim along, and we were using more air than usual. I was actually quite warm at depth; never really experienced that before. The water was about 52 F.
Well, before we made it back to the marina, my buddy signaled "750 psi", and "should we surface here or continue on, sharing your air?" Now, this was basically a night dive, so communicating something that complicated in the dark is, well, I didn't get the whole thing, but I did understand that she didn't have enough air to make it back to the marina at depth, so I gave her the thumb. So we did a "blue water ascent" with no visual reference. We've practiced this before, and actually didn't do terribly bad with the ascent and safety stop, but it was a bit up-and-down on the safety stop. She surfaced with 450 psi and I had 700. Then it was a long surface swim back.
1. I did not keep track of her air after the turn, so I was a bit surprised when she stopped and showed me 750 psi.
2. I did not pick up on the signals that she was getting anxious. It would have helped if I had signaled her to calm down earlier in the dive.
3. I let the fact that she was stressed cloud my judgement. Instead of calming her down, I let my stress level go up. Not terribly bad, though; in fact neither one of us was really all that stressed, and so I'm sure a lot of folks reading this may get the impression that the whole thing was worse than it actually was. It's just that we should have done better.
4. I should have shot the bag for our ascent, but, even though we have practiced this, I'm still not super-proficient at it and I didn't want to add another source of stress (see point 3).
5. We didn't discuss the contingency that the site may not be deep enough for our plan, so then what? One reason my buddy got stressed is that she was focused on reaching 90 ft, and when it looked like that wouldn't happen, she started swimming faster, using more air.
6. Even though we've worked on night signals, this dive made clear that we need to get better at signaling in the dark.
In the end, we didn't really come that close to disaster, it's just that we ought to know better. I've had dives where "if one more thing goes wrong I'll be in a world of hurt". On this dive I feel that, even though things were not going according to plan, we weren't really that far out of control and we probably could have handled one or two more unexpected snafus, but I'm glad I didn't have to find out.
The plan was to do a deep dive, to 90 fsw. We calculated our turn pressure would be higher than rock bottom, and used the largest cylinders available, 100 and 95 cu. ft. We had gotten to about 80 ft nearby, so we figured it was about the same here. Well, it didn't get that deep; we maxed out at 69 fsw. So basically it was a long sideways swim over a mud flat. When we reached our turn pressure, we gave up on the planned 90 feet and turned back. We didn't make it all the way back at depth, and had to ascend in "blue" (actually green) water.
I don't know why, but on this dive the water just seemed "thick". I mean, you know how you glide a bit after you stop kicking? Didn't happen this time; as soon as I stopped kicking I'd stop dead. Weird. There wasn't any current to speak of; I mean it must have been moving something in the vicinity of 8 seconds to go 1 foot. Anyway, the point is, it seemed like a lot of work just to swim along, and we were using more air than usual. I was actually quite warm at depth; never really experienced that before. The water was about 52 F.
Well, before we made it back to the marina, my buddy signaled "750 psi", and "should we surface here or continue on, sharing your air?" Now, this was basically a night dive, so communicating something that complicated in the dark is, well, I didn't get the whole thing, but I did understand that she didn't have enough air to make it back to the marina at depth, so I gave her the thumb. So we did a "blue water ascent" with no visual reference. We've practiced this before, and actually didn't do terribly bad with the ascent and safety stop, but it was a bit up-and-down on the safety stop. She surfaced with 450 psi and I had 700. Then it was a long surface swim back.
1. I did not keep track of her air after the turn, so I was a bit surprised when she stopped and showed me 750 psi.
2. I did not pick up on the signals that she was getting anxious. It would have helped if I had signaled her to calm down earlier in the dive.
3. I let the fact that she was stressed cloud my judgement. Instead of calming her down, I let my stress level go up. Not terribly bad, though; in fact neither one of us was really all that stressed, and so I'm sure a lot of folks reading this may get the impression that the whole thing was worse than it actually was. It's just that we should have done better.
4. I should have shot the bag for our ascent, but, even though we have practiced this, I'm still not super-proficient at it and I didn't want to add another source of stress (see point 3).
5. We didn't discuss the contingency that the site may not be deep enough for our plan, so then what? One reason my buddy got stressed is that she was focused on reaching 90 ft, and when it looked like that wouldn't happen, she started swimming faster, using more air.
6. Even though we've worked on night signals, this dive made clear that we need to get better at signaling in the dark.
In the end, we didn't really come that close to disaster, it's just that we ought to know better. I've had dives where "if one more thing goes wrong I'll be in a world of hurt". On this dive I feel that, even though things were not going according to plan, we weren't really that far out of control and we probably could have handled one or two more unexpected snafus, but I'm glad I didn't have to find out.