We Need to Talk About Our Mistakes So We Can All Learn

We Need to Talk About Our Mistakes So We Can All Learn

It doesn’t matter what level of diver you are or the experience you have. In the end, we’re all humans and as humans we make mistakes. It’s also in our nature to avoid admitting to them, but I feel the right thing to do is to acknowledge it, talk about it, so we can learn from it.

I thought I would take the opportunity to share a story of a deep dive I conducted 20 years ago where I got into trouble. My body knew I was in danger and it took all of my training and will to fight the voices in my head yelling at me “DON'T PANIC, but you need to get out of here NOW!” I was so fixated on achieving a target depth that it paved the way for a series of mistakes to unfold.


An action or judgment that is misguided or wrong

At that time I had been Technical diving for 7 years with approximately 500 decompression dives and had been teaching Technical diving for 6 out of those 7 years. So I felt quite confident diving deeper than 330ft/100m and that I had a very good understanding of what was needed to plan and safely execute deep technical dives as far as I was concerned.


Overconfidence from repeated experience performing a task

We have an almost unlimited number of deep walls you can explore here British Columba and one of my favourites is known as the “The Power Lines” up on the Sunshine Coast. This site is one of the only places where we have hard coral shaped like large fans which are a rare occurrence in our waters. The coral fans start at about 140ft/43m and get larger the deeper you descend. Some of the larger corals I’d seen before were in the 280ft/85m range, but as far as I knew at that time no one had explored past the 300ft/90m depth. So, in 2002 I decided to conduct exploratory dives to see if the corals continued deeper than the 300ft/90m mark.

Image courtesy of Lee Newman


My goal for this dive was to explore the wall past 350ft/106m to a max depth of 400ft/120m with a bottom time of 15 minutes. I know that doesn’t sound like much time on the bottom, but for those brief minutes spent at that depth it would cost me 2 hours of decompression obligation before I could surface.

The plan was for me and another team of divers to descend together to a depth of 350ft/106m to their max depth, and then from there I planned to go alone the last 50ft/15m. I think it’s worth mentioning that there weren't a lot of people in my community back then who I could do really deep dives with, so I didn’t want to take on the responsibility of encouraging others to dive this deep. Once I left the bottom, the plan was for me to rejoin the other team on my ascent. We all knew the site well, so we weren't overly concerned about finding each other during the ascent part of the dive and set a meeting place along the wall at the 180ft/55m mark. However, this did mean that I would be spending 15 min alone below 200ft/60m.

As we were gearing up and preparing to get in the water, our boat captain yells over that there's still some current running from north to south in the channel. We knew we were on a flood tide, but were at the tail end of it. The three of us had a quick discussion about how this might change our plan, but the decision was made to go ahead and we splashed in.

As I waited for the other divers to jump in I could feel the current pushing at me, so to hold my position I had to hang on to some rocks on the wall rather than kick. I remember thinking “wow this is not ideal”, the water was still moving but we somehow managed to stay together. As we started our descent, the wall was dropping at a 90 degree angle. It was important for us to use the angle of the wall to our advantage as this would allow us to gain some speed in order to get to target depth as quickly as possible and get away from the surface current. With the amount of equipment we are wearing, we are very heavy in the water and you drop like a stone. If you have ever made a quick descent down a vertical wall you know it can be a bit disorienting, you feel the sensation of free falling but upside down.

As we pass 250ft/76m the light from the surface is gone, our world has now become shrouded in darkness with just the beam of our lights as guides. Just ahead, I see small groups of very large rockfish. They swim towards us not scared in the least, and they seem to be coming out to have a look at these noisy things passing them by. We are now passing 320ft/97m and I hadn’t seen any coral fans deeper than 300ft/90m yet. Perhaps they have a sweet spot on the wall or are deeper.

The visibility was excellent and I can see the bottom where the wall has turned into a sloping shelf, littered with very large boulders some the size of a small car. I check my gauge, we are almost at 350ft/105m. I turn my light back and give a nod of my head to signal to the others this is where I leave you and continue alone. They signal me back with a slow turn of their dive lights “OK”, but it was as if they were saying “ok, see you in 20 minutes man”. I can hear them inflating their BCDs so they can hold at their planned depth of 350ft/106m. I take a quick look back and all I can see is their lights becoming dim as I descend away.

The slope keeps dropping but not as sharp a drop as I thought it would be, and I feel like I’m gliding down and flying over the boulders. I’m 5 minutes into my dive and I check my gauge as I’m passing 370ft/112m, my bottom gas pressure is where it should be but I still have some way to go.

I start to feel a resistance and I realize there is a slight current hitting me on the right side. I didn’t expect to have to deal with current at depth. The seafloor is almost flat now and I am having to navigate my way over the boulders. I’m forced to start finning instead of gliding to avoid hitting one rather large boulder. This course of action puts a fair amount of stress on me, this would be a mistake.

I check my gauge and it’s reading 396ft/119m. I had become way too focused on getting to my target depth, that this distracted mindset has made it more difficult for me to take in my surroundings, another mistake.

As I begin to pass a boulder that is on my right, I’m still not registering the current and decide to pick a path around the boulder to the left. I have finally hit my target depth, so after I round the boulder, I’ll start making my way back to the wall and end my bottom portion of the dive. As I turn right around the boulder, I go head on into the current. I didn’t take that information in and that was a critical mistake!

I notice that my speed has slowed down and I start to feel a little out of breath. If I had been more aware, I would have turned left instead of right and away out of the current. At this depth you want to exert as little as possible or not at all. I doubt any of what was about to transpire would have happened if I hadn't been so fixed on achieving my target depth. I was allowing my ego to play a part on this dive, another mistake! I start to feel light headed. At first I think that it’s just a combination of narcosis along with a quick descent. Although, I remember thinking to myself, “I’m breathing harder than I should be”.

This is when it first hits me, it was not a thought in my head but a feeling that came over me - THIS IS NOT RIGHT! It's then that both my feet start to tingle. Almost right away the feeling starts to move up my body. It feels like heat on my skin along with weakness. Again, it was a feeling and not a thought “that I'm in DANGER”. I start to feel frightened and I can feel my heart beating hard. It was like my body knew I was in trouble and was trying to force my brain to make the decision to run, run away, get out of there. I can feel the panic starting to take over, and I have never had anything like it happen to me before. I think “ok just get around the boulder and I need to get back to the wall”.

As I fin and I look up towards the wall, it feels like it’s darker. I check my light to see if it has stopped working, but it’s still on. The current pushes me, and my fins hit the boulder which prevents me from moving. I look up again and realize it is getting darker. The peripheral area of my vision is starting to shut down and it’s getting darker and starting to go black; it was like looking through a tube. I'm feeling weak and tingly all at the same time. My body is trying to get through to my brain and I hear a voice in my head shout “GET OUT OF HERE or you’re going to DIE!!

I'm still moving away from the boulders and towards the wall. The voice is now yelling “GET OUT OF HERE NOW!" I'm trying to calm myself and fight to not panic, but I realize that I don’t have the time to try to understand what’s happening to me. It's taking all my will, strength, and training to fight the urge not to start kicking for the surface as fast as I can. I say to myself “ok, you need to leave NOW, forget the wall”. The voice in my head yells "DON'T KICK, use the BC and get out of here NOW!" I turn towards the wall as a point of reference and lay on the BC inflater hard. I can hear the gas filling the BC, but I realize that I don’t have much vision left. As the BC starts to take over and pulls me up, I look down and the bottom is gone. The wall is now a large greyish thing running past me way off in the distance. I look through what feels like a keyhole and realize that only my right eye is working.

I know I must be ascending way too fast, but I need to get out of there. I feel my body is still trying to take over, and I'm fighting it as hard as I can to stay calm. The voice yells, "DO NOT KICK! "

I’m talking to myself “you're going to be ok man”. Talking to myself helps a bit and it’s then I realize that I'm hyperventilating. I try to slow my breathing down. The voice repeats "Don't kick, don't kick, if you kick you're going to pass out and DIE"!

I look down at my depth gauge and see that I'm coming up on 300ft/91m feet. I’m talking to myself trying to stay calm, "you’re going to be ok and you're going to stop at 260ft/79m no matter what!" The tingling feeling is still strong and I'm aware that the weakness is taking its toll, I look down at my hands and they are shaking gently. My vision is starting to come back and I have my breathing much more under control. I’m taking big slow breaths and am saying to myself “stay calm man”. I look forward and realize the wall has angled away from me, I’ve lost sight of it. I look back and forth and I realize that any direction I move could be right, or wrong. Or I could end up heading out to the middle of the channel where I know there is boat traffic. “STOP” I say to myself, you're overthinking it. You didn’t turn away on the accent so trust yourself. I know it was in front of me, so I let myself slowly, gently fin in that direction and hope this is the right direction. It must be? The best news is that the yelling in my head is finally gone.

As I take more slow big breaths, I’m thinking about what I’ll need to do if I don’t find the wall. The boat will hopefully see my SMB and know that I must be off the wall. “Come on be there”, I’m saying to myself. I keep finning slowly. Then, from out of the darkness, I see the WALL! I feel this huge relief wash over me and I make my 260ft/79m Deco stop.

At my next stop 230ft/70m, my vision is back to normal and the tingling is starting to fade. Because of my rapid ascent from 400ft/120m to 260ft/79m I have messed up my window for meeting up with the other guys. I had left a number of minutes early. I thought briefly about trying to head south along the wall where I thought they would be, but with the weakness and tingling I was nervous that exertion from finning might make things worse. I realize I feel scared and shaky, I’m still very on edge. I look at my pressure in my back tanks, 1000 psi, “wow I went through that fast!” I only have a handful of 1 minute stops left on my bottom gas, and once I'm at my 120ft/36m stop. I’m switching to Nitrox so I can get off the bottom gas. The next number of stops go well and the tingling has passed. I'm almost feeling normal, but my hands are still shaking a bit, I think to myself it must be adrenaline in my system.

At the 120ft/36m decompression stop I looked up towards the surface and I can see the trees on the wall at the surface...what the hell! The first thought was “I’m too shallow”. I’m struggling to figure out how the hell did I get so shallow? Are my computers not working? I’m looking at both my computers and they are reading 121ft/36m and 120ft/36m. How can they both be wrong? As if there hasn't been enough on the dive already, dammit. Then I look to my left, south along the wall and there is a large group of divers 7 or 8 that are about a minute away. I move up towards them slowly from my 120ft/36m stop to the 110ft33m stop.

A couple of them look up and give me the are you OK sign. HELL NO! is what I’m thinking but I return the gesture. I move closer and point at the one diver's console and ask to look at it. He rolls it over and I can see that I’m at 110ft/33m. A wave of relief rolls over me and I give him a nod and an OK signal and then they turn back to their group and carry on. I start laughing at myself and my mask starts leaking from the grinning. I clear it and it fills again. I’m talking to myself, “hey you need to relax man, you're ok, IT’S OVER, you're going to be ok.”

The laughing makes me feel better and it’s only then I start feeling safe again. I don’t know what those divers must have thought about this weirdo diver that comes out of nowhere with six tanks hanging out by himself asking to look at depth gauges, but CHEERS guys, that was the turning point for me. I was going to be ok!

The rest of the dive was smooth and towards the end, I found the other team finishing their deco as well. I apologized to them for not meeting up with them as planned. The weakness from the adrenaline lasts the rest of the dive and for some time afterward. My head is hurting and I have a mild headache. I never said anything to anyone even after I'm safely back on the boat. I just keep my mouth shut as I want to relax and feel calm. I didn't have any problems that night or into next morning resulting from the fast assent coming off the bottom. I felt it was important for me to get back in the water, so on the dive the next day I keep it easy and keep a close eye on myself. Afterwards, I did mention it to the other dive team that I had some troubles and went over with them some of the events. They felt bad about leaving me on the dive, but I said it was all my fault there was nothing they could have done to help me in that moment. Fact is, if I had to communicate, that might have been the tipping point to a blackout. No one being there with me was all on me.

After that day for a number of months, whenever I would start to feel the sensation of even a little narcosis and a higher gas density on deeper dives, my body would start to try and take over with a sense of impending doom. "YOU NEED TO GET OUT OF HERE" came racing back. Not to the same level as before, but it was there. I would have to stop and take some deep breaths and talk myself through it. Over time, this feeling would pass. I did get back to deeper diving about 6 months later once I felt that I had recovered mentally. I eventually dove past the 400ft/120m mark, but this time I was very aware of my environment and how I was feeling every step of the way. I also wouldn’t dive unless the conditions were perfect. I think it’s important to talk about our mistakes rather than hide them in the hopes that other divers might learn from them. I take this approach in all my classes I teach, but I found writing about a near death experience harder than I thought it might be. It took me some time to reflect and to remember the course of events clearly as it all happened very fast.

I will never stop wanting to explore our oceans and lakes. Since then I have become a cave diver, CCR diver, and I have made over 1500 technical dives, most without incident. I have managed never to repeat the mistakes I made on that dive. My advice to you divers reading this is, when diving, focus on the overall process and not the outcome. Take your time, you will make some mistakes along the way and that’s expected. It takes a lifetime of experiences to really master anything worthwhile.


Written by Hamish Tweed

Hamish started diving 1991 while visiting a friend in Victoria British Columbia and by 1995 he was working full time in the diving industry. In 1998 Hamish earned his IANTD Instructor Trainer and Advanced Trimix Instructor certifications and was teaching advanced technical diving as the Head Instructor for IANTD Canada. Through his own business that specializes in technical instruction and travel, Hamish has been teaching technical diving for over twenty years certifying hundreds of technical diving students and has organized and lead over a 100 trips and expeditions throughout BC, Canada and around the world.