AfterDark
Contributor
Let me begin this post with a two brief caveats. First, I have no facts whatsoever about the Catalina incident. Second, I am not speculating. But I do wish to make an observation concerning what it feels like to hyperventilate whiel on SCUBA. (I am not suggesting that this is what occurred in this case.)
Years ago, when I was young, I went diving in cold water with an experienced Divemaster. I hyperventilated. We were at about 65' of depth. I felt like I was not getting enough air and that scared me. I switched to my Octo to see if if would give me more air.
I still felt air-starved, but I wasn't. I just felt that way. I signalled to my buddy that we need to ascend and we aborted the dive.
We slowly ascended and surfaced. All turned out fine. I learned a valuable lesson.
My point here is that this experience taught me that when hyperventilating it is possible to feel like you're not getting enough air. That can scare a diver, particularly a new diver.
I don't mean to hijack here but maybe this might be useful. In the case above a gentle pressure on the purge button to cause some free flowing might be enough to convince ones own self that enough air is coming and quell some of that feeling. Make the trip up better. Just a thought.